It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937 If you're interested in learning more about earth grounding your panels, I found this resource on the diy solar forum to be extremely helpful! FilterGuy does a great job explaining things for even someone like me to understand! diysolarforum.com/resources/grounding-made-simpler-part-3-solar-panels.160/
@@JOHNDANIEL1 all I know is I got shocked like no tomorrow grabbing the handle to my shed and if running a ground lug to my house grounding rod stops that then I’m all about not getting shocked!
@@JOHNDANIEL1 it’s the poor isolation of PV from the AC of the all in one inverters it’s “AC power” that’s the shocker checked that with a meter not “ DC “it’s a known problem with many of the HF all in one inverters from what I understand. So the ground is to dissipate the AC back current off the frames.
No. Its nothing to do with cheap inverters its the design. The pv bus is switched twice per mains cycle to the neutral with alternative polarity. That basically means the panel potential moves up and down hundreds of volts as it switches with respect to earth because it is usually tied to neutral. That is not a problem because your pv voltage will kill you anyway. So why does the frame feel live? Its because it is capacitively coupling to the panel. Think of the pv cells as one plate and the frame as the other plate of a very small capacitor. Because the capacitance is tiny the AC current that flows is tiny. You can measure 50 to 150v with a suitable meter. If you ground the panels then you will no longer feel this. Does it matter? Not really. But the switching potential on the frames does emit radio interference and so grounding it reduces that a lot. But its nothing to do with cheap inverters its just an efficient way to do it and galvanic isolation will just introduce more loss.
Awesome video and purfect example of why grounding the frame is important. Cracks me up on other channels complaining about voltage and inverters are unsafe bla bla bla but they dont have the system complete🤷♂️ Great job Subscribed💥🤘
Adam, as it was mentioned here already most likely what you see is High Frequency AC coupling from MPPT charger (built in 6500x). It's not 60Hz AC coupling/leakage from the inverter part of 6500x.... That explains why you see what you see... Most of the cheap meter won't show properly 100kHz frequencies. You better use a cheap oscilloscope for that. I won't be surprised if you also use a multimeter with LoZ setting and it will read almost nothing. I think I saw similar things with my 6500x when I was trying to put an EMI/RFI filter right at the PV input. That thing (it's internal MPPT in particular) emits quite a lot of interference on HF frequencies (Short waves) into the air :( It's all about internal circuit design. Grounding the frame is possibly the easiest thing to "deal" with this issues. It still will be coupling that 20-100kHz but you won't feel or see it :) Coupling is happening between PV cells and the frame... That structure forms sort of a capacitor.
Make sure the bare copper is not touching the aluminum frame. The copper and aluminum are dissimilar metals and with bare contact will cause corrosion. It’ll eventually eat into your aluminum.
Good point about the galvanic corrosion. That will happen to the clamps over time, assuming they aren't anodized. Or even with Aluminum and a stainless screw on the clamp.
Thanks for the video. I am dealing with a lot of the same issues. I have two EG4-6500ex-48 and I am getting voltage on my racking and buzzing when I touch the panels frame. Also got low reading in the 40V ac with my cheap meter and 140v ac with my nicer fluke meter. 1 st world problems I know but it sure is frustrating. I have spent a good portion of my life listening to Signature Solar’s hold music.
Thanks for vid. Newest NEC codes say panels/mounting need to be grounded. I think in the past some people considered it optional and only as a means of lightning protection or something. NEC 690.41
Regarding the craftsman meter. It depends on the input resistance of the meter. I have a high end fluke that is very sensitive. It reads 200 volts AC o the PV lines but my cheaper Chinese meter reads about half that.
The difference in your meters' voltage readings probably has to do with the meter input impedance. The source of the AC voltage you were detecting is capacitive coupling to the back-fed AC power. This normally is a very high impedance source so very little current in available. A high input impedance meter will register a higher voltage than a lower impedance (cheaper) meter because the lower impedance loads the source & pulls the voltage lower. It would be interesting to check the current drawn by each voltmeter to verify the actual power (volts x amps) involved. The charge you have detected is unlikely to be dangerous, but in the event of insulation failure (conductive voltage back-fed), it could become lethal. That's the whole reason for safety grounds in appliances: the internal voltage may energize the appliance chassis (outer case) in the event of internal insulation failure & should you touch a grounding source & the appliance case you become the conductor of lethal currents. Modern standards allow double insulation in place of a safety ground connection to the case. There is also value in grounding the panel frame if lighting frequently happens during storms in your area. The safety ground could prevent the lighting current from being routed into your home over the power leads by diverting it at the panels.
HOWdy A-D-L, ... Thanks - this is one of the 1st things that I did on each of my SIX (6) Arrays ... Grounding LUGS + 6-AWG Bare Copper Wire ... into my ECO-WORTHY Six String Combiner-Box ... 36 PV Panels = run in a 6S / 6P configuration ... COOP ... the WiSeNhEiMeR from Richmond, INDIANA ... ...
Good morning Adam With my system I think I’d be fine because I’m using sign post which are metal and they are into the ground at the bottum Update on my new growatt 3 5KW System. Such a great setup. Don’t get me wrong I’ve had a few codes but nothing like the pile of garbage I had with the 2 EG4 6kw inverters And the flickering is pretty much gone And I’m running my whole house. Air compressor jacuzzi tub washer dryer and all the normal stuff Super happy with my change in the system. Have fun Adam and keep up the great solar videos coming 👍🏼
Glad to hear after so long of you having issues, your finally able to just use a system and almost forget about it because it just works! Thanks for sharing!
I just occurred to me I have a single ungrounded 435W panel setting on pavement against the house with an Enphase micro inverter on it, I've never noticed any potential on the frame, even when wet. I'll have to test it now that you reminded me!
Enphase inverters are grounded internally to the chassis through the green wire in the 240vac trunk line. The instructions for Enphase clearly state no external ground required. I have 36 of them and no external ground. I passed inspection.
A great video …. Had the same issue my limited understanding is due to transformer less inverters get capacitance leakage on the dc lines from the ac. I was getting about 30v to earth on mine from a Growatt 5000es. There are specific washers and plates that cut into the anodising to further help get that stray current ground. I got ac and dc current on the panels also
you get the same effect with a bench PC . if your disconnect the earth wire so the PV power supply is floating, you will get some shocks, like static electric cos of the way the switch mode power supply (ATX) works, its a capacitive coupling - annoying getting zapped.
Most installers appear to just ground the aluminum racks, not each panel. When I worked at Edwards AFB, CA, you soon learn to touch a water fountain with your knuckles. A spark would jump 1/4" thru the air. Ditto when I lived near Chicago in winter, in a building with no humidifier. That little buzz is nothing. Likely from current leakage thru the inverter. But, smart to ground the frame in case the inverter shorts grid-power to the frame via the solar cells.
When I was installing a ground washer was placed between the panel and the frame that digs into the metal of both panel and rack which was per code but I still put a ground lug on each panel anyway. The ground was hooked to the rack then each panel down the line. Haven't noticed much if any corrosion between stainless set screw lead alloy ground lug and copper ground wire but I live in the desert so not so much moisture
I figured it would get absorbed by the battery and by the capacitors in the charge controllers. But I guess not. Wow. New information.... that's why I like your channel! I would posit that the power factor of your AC loads would also have a significant effect on the ripple you are seeing on the frames, since poorer power factor directly feeds-back through the inverter to the DC side.
Appreciate that! Hard to say. I’ve found most things with a poor PF cause my lights to go nuts in the house. I’ve only found 3 things in the house with poor enough PF to flash the lights.
@@eddietee6305 The issue being talked about here is a more indirect path where some of the AC couples back into the DC wires. There are three ways this can happen. * The first is direct coupling backwards through the AC inverter... it ends up looking like ripple on the DC side. * The second is direct coupling backwards through the AC inverter due to reverse current due to a poor power factor. Basically, when there is a poor power factor on the AC side, some of the energy will actually couple back through to the DC side. In large inverters this energy is mostly captured by capacitors and re-fed back into the inverter. In cheap inverters this energy just couples back to the DC side and ends up as stronger ripple on the DC side. * The third way is through EM radiation. Any AC waveform radiates energy. The energy will couple into any wires in proximity to that EM radiation (regardless of insulation). That is how AC winds up on the frame. We see similar issues crop up with AC breakers, for example. If you turn off an AC breaker and there is no load on its output grounding it, i.e. the output is open, you will measure significant AC on the output even though the breaker is open. Usually somewhere around 50-80VAC. Very little current can couple through, but it is certainly enough to give you a shock. The effect is even more pronounced with a contactor or relay... sometimes enough energy couples through that LED lights will continue to flicker or light dimly even though the switch / relay / contactor / breaker is "off". So that is how we wind up with AC on the solar panel's frame... and it is indeed often enough voltage to give someone a significant buzz. Grounding the frame fixes the problem. But determining the best place that the frame should be grounded to is actually a really difficult problem for a multitude of reasons. i.e. should it be to a nearby house ground wire from a plug? Do you have to run a ground wire all the way to the house grounding rod or main service breaker box? Do you need to sink another grounding rod into the ground near the house? There is no right answer.
This panel can put out close to 100 watts ruclips.net/user/postUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.
I read somewhere guy had an EG-4 6500 his utility called him said he was back feeding turned out the inverter was back feeding through the input side on a off-grid inverter. The panel not the only place it back feeds voltage. One reason I went with a Sol-Ark If your off grid don't want to spend the extra money have to work around their issues like you pointed out you can save the money.
@@AdamDeLay07 I'll look around might have been on DIY forum can't find it now I'll keep looking or could have been a YT comment on a video review of the 6500.
Good Video much to consider... On a side note: I don't know if this will someday go national, but Insurance companies in "our" area are starting to cancel home policies that have more than 10k of solar panels attached to their roofs. The risk of fire is very high if not installed correctly. It's a catch 22 for people who don't have a lot of property to put the panels on the ground...
Interesting. I also have wooden frame ground mounts. I grounded mine during installation as required by the NEC. I drove an auxiliary ground rod at the panels and also bonded them back to my service panel. I haven't noticed anything when I've touched the panels, probably because of earth grounding and bonding. I'm using the EG4 6500 inverters as well. I'll have to check for voltage from panels to ground. I'm surprised there is any voltage at all with a grounded panel system.
Yeah apparently the cheaper HF inverters don’t have any isolation between the PV and AC. At least that’s what I’ve heard from people who know a whole lot more about this stuff that I do.
@@AdamDeLay07 Yes, that's correct. Or more specifically, they don't have high quality energy recovery from the AC that couples back through the transformer, or any shielding from the EM.
I'm not sure whether you are allowed to ground to both location at the same time when the grounding rods are really far apart. At a minimum, see if there is a significant DC voltage differential at the house between the ground wire coming in from the array (while disconnected from house ground), and the house ground. Having a really long ground wire going across the field could increase the damage that nearby lightning causes by giving it a low impedance path into the house, which might not otherwise occur.
@@junkerzn7312 This is a great topic for conversation. First NEC 690.47B does allow for and additional ground rod at the panels, in fact in that same section, "the support structure for a ground mounted PV array shall be considered a grounding electrode", ground mount system grounds are addressed. To me a steel ground mount racking system really can't be isolated from acting as a grounding electrode. A wooden one probably can, so long as it's not damp or wet. I've watched Mike Holt's videos who would agree with your scenario. I would also agree if either one of the DC power carrying electrodes was grounded, or there were no grounding conductors between the array and building service panel. Something to consider too, would be a direct lightning strike to the array. I understand that no system would protect sufficiently for a direct strike, I do believe that a greater part of that energy would go directly to the earth ground at the panel and may in fact reduce damages to the system in the building. On my system, I used #4 solid copper to ground my array to the auxiliary ground rod, and #8 stranded to bond to the building service. As I started out saying, this is a wonderful topic for discussion.
@@backtothepast1850 Yes, total agreement. There is very little real-world data supporting one scheme verses another. The distance is going to matter a lot, too. I have a main system on the garage roof which is right next to the service ingress. The grounding for that is obvious. But I also have a bunch of panels hanging off the back deck on the entire other side of the property, 200+ feet away. At the moment I have that tied into a simple house circuit's ground but I just don't know if that is the best solution. For a remote array in a field, I'm more partial to grounding at the array since it is already partially grounded there anyway, but not feeding a ground wire all the way back to the house. Instead, I'd have surge protection at the house for PV- and PV+ tied to house ground. The idea being to protect the house systems as much as possible from damage. In that case I think sinking a second ground rod AT the house and tying it into the house ground (if the main rod is on the wrong side of the house for example) might be reasonable. But I just don't know. Really just my ruminations as an EE. But an EE is not usually a certified electrician.
check the same when turning off the inverter output but with solar still charging the battery's. probable same thing i experienced with voltronic inverters (same inverter builds, different color and branding). they seem to put ac back trough the solar input only when the inverter is making AC power. also got shocked by them when was installing metal sheet finishing around a metal roof with panels installed on the metal roof.
It’s surprising how many people I’ve heard have felt the voltage on their frames. Apparently on cheaper HF inverters, there’s no isolation between PV and AC. You would think there would be on all inverters.
@@AdamDeLay07 we all love high end Inverters but they come at a premium price, My Growatt works great two issues I have with it high idle consumption and what we just spoke about otherwise I got Power
I have an eg6500ex split phase system and I can measure 200 VAC on either of the PV connectors and I can feel some electrical charge on the frame although I did not measure. it. I also have a wood racking.
Impressive. Between the isolation in the inverter and floating the output. Yeah they're supposed to be grounded for a reason. They're metal objects and they can become live so you want them grounded to Earth potential in case there's anything wrong with the equipment or if a wire accidentally comes in contact.
I found the shocking aspect when the panels were wet. I was curious as well and after testing I thought the ac voltage on the panels was due to the solar cells producing power. I disconnected the panels from the eg46500 inverter as you did and found a small voltage still exists but then I added a small resistance load to the panels +- to get the panels producing current and the frame voltage when up so I assumed the frame voltage was a by product of the panels producing power. I would like your feedback on your thoughts.
Yeah once I discovered the “voltage leak” for lack of a better term, I avoided the panels when it was wet outside. Unfortunate I’m not super familiar with the underlying workings of solar panels. In your isolation test though, I’m assuming any voltage you saw on the frame would have been DC, correct? I guess either way it really emphasizes the need for grounding!
I have never seen that with my two 12K home system. Started up my two shop 6500EX’s….same bs before grounding. A little scary at first. I guess we get what we pay for. I didn’t even have both pos and neg leads hooked up to the panel.
Had to go back trough to find those comments. Looks like he was testing at the PV inputs of the inverters. Not exactly sure how he tested because it wasn’t mentioned, but he said his tests revealed “20VDC and 0VAC”.
Because it's not necessarily an inverter problem, it's an end user design problem. These should have been earth grounded from the beginning. This is a common problem in the DIY community. People think they can cut corners and save money, this is the result. There should be no AC voltage at your racks. I would bet he has AC/DC grounds mixed at some point. There should be no way AC voltage is present on your panel racks.
@@AdamDeLay07 I'm glad you've brought this to our attention. I'm going to hook up the 48V 3000TL LVM by rich solar in my trailer this season. I will have to test my array. I used the MidNite Solar MNDC-GFP63 in my diy combiner box.
@@Scotty2Balls Code in Canada 64-222 Photovoltaic module bonding (see Appendix B) 1) Exposed, non-current-carrying metal parts of photovoltaic modules shall be bonded to ground. 2) Module bonding connections shall be as specified in the module installation manual. Δ 3) Notwithstanding Subrule 2), bonding connectors intended for bonding photovoltaic modules and installed in accordance with the manufacturer’s instructions shall be permitted to be used. 4) The connections to a photovoltaic module shall be arranged so that removal of a photovoltaic module from a photovoltaic source circuit does not interrupt a bonding conductor to other photovoltaic source equipment. S
Thanks. Yeah I won’t even begin to understand how it all works. I do know that lightening protection is a completely separate system from normal “earthing” though.
@@AdamDeLay07 Think it would be best to earth the panels or anything that mixes metals and electricity. But also put in a higher lighting conductor. As you say , these are two different issues.
I got shocked pretty good today by my shed and I know understand why “earth grounding” the all in one are necessary! My question is did you run your wire back to your service panel grounding or directly to the house grounding rod outside? Would love to see that part! Thanks so much for the videos!!!!
I believe I saw your thread on the forum. It's not pleasant at all... From everything I've seen, it should be run back to the main grounding conductor of the structure. When I set it up though, I had it on it's own ground rod. Can't say I fully understand it, but I can tell you I don't get shocked after earth grounding the frames. From what I've read though, the cheaper HF inverters tend to have little to no isolation between the PV and AC H-Bus.
If you put another rod in, it will create a ground loop between the two rod locations. These also won't connect the two locations (home/building/inverters) to panels thus they'll have different charge levels and can still shock you. The other issue is the "loop" issue which if lightning hits it'll pass through your equipment and loop back through the rod. This doesn't happen if you have 1 centralized location to go to into the actual earth-ground Which is why it should just be ran back to the house and then attached to the breaker box ground or somewhere there
The Kline is likely an RMS meter. And get those MC4 connectors off of the ground. Check out my wooden rack that I just built. It goes to a DC assist heat pump.
Great video, and I like your discovery process. I do have a question: aside from static charge and induced current from nearby lightning strikes (or other nearby high frequency EM fields) there shouldn't be any voltage buildup between the panels and ground, and once you've discharged it, there shouldn't be any substantial voltage potential left. So why is it that your system shows a persisting voltage difference? I'm not an expert, but logically there has to be a continuous source of energy "charging" your panels' frames. I can think of two options: 1) Internal: there's some kind of "leak" in your system. 2) External: there's some kind of external source of energy, e.g.- a persisting EM field, strong enough and close enough to induce current in the metal parts of your panels. The first reason seems a lot more likely. If you find the reason for this, (and the solution:) please share it with the rest of us. Thanks
Thanks! Your exactly right, there shouldn’t be anything there. After more research, it actually looks to be a fairly common problem with cheaper AIO inverters (I always say there has to be some compromise getting all the components in the AIO inverters to play nice together). So it seems there’s limited to no isolation between the PV and AC H-bus, which then allows AC Ripple back to the panels. I still don’t understand how voltage shows up on the frames when they’re not connected to the pv lines at all, but I know it’s happening. I trust people a lot smarter than me for the explanations. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
Did you try measuring it with a Low Impedance Meter.? Most meters are High Impedance. If you stuff up, a High Impedance meter will conduct less short circuit current making them a little bit safer than a Low Impedance Meter. However, a High Impedance meter will give you inaccurate readings of 'Ghost' or 'Phantom' Voltages from Capacitive Coupling and sometimes from Inductance. Switch Mode Power Supplies and Inverters, which both have high frequency switching creating some coupling, and some the cheaper versions have a capacitor coupling the (relative) low voltage and extra low voltage sides of the switching units. Some can also contain Noise Filters between the LV and ELV circuits also.
Adam, one note, you mentioned grounding the panels on the shed roof for protection in case it gets hit by lightning but earth grounding is not for protection against direct lightning strikes. I recommend watching Mike Holts video on grounding and bonding where he does a wonderful job explaining the difference and purpose of the two. You are correct that earth grounding allows for dissipation of any static buildup or electrical surges due to "nearby" lightning strikes.
I'm gonna trim that comment out of the video to avoid any confusion, because it obviously isn't the reason to ground the panels. I really appreciate you pointing that out!
@@AdamDeLay07 haha dude I had the same issue and I spent countless hours searching and watching youtube videos trying to understand the purpose of grounding and bonding. Mike Holts videos are the best reference that I found for understanding the purpose of both and to understand the best code compliant techniques for wiring
I followed Mike Holtz explaining earth grounding of solar panels and bonding the ground of the system. I have 12 panels on an adjustable wooden ground mount. I have none of your issues with AC voltage back feeding the panels. In his series he definitely suggests not earth grounding solar panel arrays or generators. He does however suggest earth grounding the inverters and bonding all components including the transfer switch if used. This is a separate grounding rod specifically for the solar system and all components. I also installed EMP SHEILD units on my main grid 200 amp panel. The 2 inverters and my batteries. My system has worked flawlessly for about one year now and my panels are not earth grounded. Perhaps you have not grounded your system properly causing the back feeding to your panels. Please check out Mike Holtz and his series on grounding and and bonding. His expertise is used in court cases and has been documented many times. Personally I don't think your problem is with earth grounding your panels. I think it's with the way you earth grounded your system. Good luck and I hope this helps.
Sorry but I have to disagree with your statement. A separate roof mounted lightning rod ,or rods hooked to a earth grounding rod will dissipate a lightning strike. A grounding rod for an electrical system can actually attract a lightning strike. As will a metal light pole, flagpole, basketball goal, etcetera. Including your roof mounted and ground mounted solar panels or backup generator. Check out Mike Holtz!
It might be interesting to test the current to ground from the panels to see how much power is going through. Also something that is confusing me, if the inverters are in fact injecting AC power to the solar panels how is it showing up on the frames? Every panel I have tested there is no continuity from either the positive or negative wires to the frame. ???
When I looked, the current barely even registered on the meter, so that's why I barely feel anything when I touch the panels. Unfortunately I don't understand how it's all happening either. Someone much smarter than me told me (and I'm gonna try and remember exactly what he said) that "in cheaper HF inverters, there's no isolation between the AC and PV." Because there's no isolation, you really wana make sure to earth ground the panels to dissipate any leakage. This might help a little bit: diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
So interesting that many of us have the same inverter clones but varying issues. This made me curious. I have an SP6548 that has been giving me issues with flickering from day one. It too had ac voltage on the frames of my ground array before I grounded them. I borrowed aMPP LV6548 that I hooked up yesterday and 0 flickering lights. This video made me want to check the panels. Just pulled my grounding rod and checked... 0 ac voltage on my frames. Is this voltage leakage from the units another defect? Brought up a great point, always ground your panels. Thanks for the video Adam.
Thanks! That’s interesting that you showed 0v when testing the LV6548. I’ve heard those can have a nasty zap. There has to be another common denominator. I’m wondering if it’s using AC In. Have to test to find out.
@@AdamDeLay07 Watts247 has the LV6548's on sale right now. After all the headaches and what I spent on filters, rma shipping, new bulbs, dimmers etc .. for 1k... just cutting my losses at this point. Something deff not right with these units.
If I wasn't worried about things being thrown from the mower at the panels, I might actually do that! The wooden frames get the panels up high enough to keep them from being hit.
@@djblingazworld yeah it all depends on the space you have as well as the voltage specs of your solar charge controller. In this video, the problem was solely due to the EG4 6500. It doesn’t matter what panels you have, you would still have the same problem.
FYI: I used a 4" Grinding Wheel to remove a "patch" of ANODIZATION to BARE Aluminum where my Grounding-LUGS attached with Stainless-Steel 1/4" SAE Bolts COOP ...
Another possible reason for the difference in meter readings is that the inexpensive meter might not take RMS measurements. So, if the AC being measured is not a sine wave then the measurement may be different. Why might it not be a sine wave? Ask the inverter :)
Saludos, solo para estar seguro de que entendí... ¿lo ideal es que el metal/aluminio no toque dos paneles a la vez y asi no hay que ponerle cable de ground? ¿O el metal/aluminio que no toque dos paneles a la vez y luego ponerle cableria de ground?
Seré honesto, no estoy exactamente seguro de cómo o por qué está sucediendo, aparte del hecho de que el inversor de alguna manera está enviando voltaje de CA de vuelta a través de las líneas fotovoltaicas. Resulta que este es un problema bastante común con los inversores de HF más baratos. He recibido bastantes respuestas de personas que usan el mismo inversor de estilo (ya sea SunGoldPower, MPP o EG4). Al mirar a través del DIY Solar Forum, parece que estos inversores más baratos no tienen un aislamiento adecuado entre el PV y el AC H-Bridge. Https://diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
My question is this... even if the invertor is sending a signal out to the panels. How is it that the frame of the panel is connected to either the positive or negative wire of the panel. Do you show concuctivity between either of those wires and the panel frame? I'd hope not! In short.. how does ac on the wires translate into ac on the panel frame? My guess would be some kind of incuction from the panel traces closest to the frame.
I didn't see any conductivity between the panels and the frames. I've tried to understand how it's actually happening and haven't been able to figure it out myself, but I'm not the only one experiencing this issue. It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
@@natesdiysolar So after talking with someone who had 2 lv6548s that got bit with the voltage on his panel frames, we came to the conclusion that he might have had strings from 2 different inverters on the same array, and they were being electrically connected by the washers holding the panels down. That would increase the voltage on the frames. Just FYI.
Very interesting discussion. I have two LV6548 and... 6:05 He's not the only one that got popped, don't ask haha 12:19 I'm seeing around 90V on mine with a Fluke 14:21 I'm no engineer but I suspect that, while there is voltage, it's just leakage current (very, very small amount). Perhaps the Craftsman has lesser resistance between the probes? Don't know, just a guess.
Thanks! I’ve heard from several people who’ve been…”surprised”. 😁 I imagine that might be the reason the craftsman didn’t show the same info. Especially since it showed proper voltage from the grid power.
@@AdamDeLay07 Here's a fun one to add - if you have 2 inverters connected to form standard 120/240 power and you have a solar array connected to each inverter, you have nearly 200VAC between the frames of both arrays!
@@LithiumSolar it’s funny you mentioned that. I was talking to someone else that had multiple strings from multiple inverters on a single array. The strings in the array ended up being bonded together due to the mounting hardware. Got a really good zap. Said he’d never felt anything like it before!
@@AdamDeLay07 I was just wondering what putting a Ferrite filter on the PV lines would do. I'm just getting into solar and don't have the equipment yet to try myself.
I would be more concerned as to why the system is back feeding AC into the PV array.. I have a similar setup where my panels are literally on the ground or blocks, and I move them around as well and have not noticed this. Iv been thinking of grounding my panels as well. How many watts is your pv array..
@Adam De Lay I'll do some research once I get my lv6548s running. Wonder if it has to do wth ground neutral bond. Im thinking of off loading the charging to a Victron mppt and just using the inverters as inverters only.
@@natesdiysolar that’s an interesting thought. Wonder how the inverter consumption would change if you never use the mppt? In my case, the only time the fans work really hard is when I have a lot of Solar coming in. Even with larger loads, it doesn’t seem like the fans run that hard.
It sounds like you have a floating earth bonding issue??..might be a good idea to also check your house earth bonding as well??.. could be a issue with the big inverter earthing (by yours mains fuse board).. sounds like it's floating??
Thanks for the comment. My main ground is intact and not floating. Apparently this is a known problem with cheaper HF inverters. There’s no internal isolation between PV and AC.
Lot of people say to ground the panels to a different ground line then the houses main ground line....the panels on your roof are grounded to the main line of the house? Or do they have a different independent line?
I believe code states that it's all supposed to be going back to the main house line. Here's one of several videos that have helped me "understand" the confusion that is the codebook... ruclips.net/video/cZo8ict33_I/видео.html
a small note about your measurement on 8:17 - the black wire should have been plugged in on the com terminal for VAC measurements! Concerning the measurement difference on 13:20 - this might have to do with the AC waveform - as the KLEIN Tool Multimeter is a TrueRMS and the cheap one is probably not -> the "true RMS" has most probably have the more correct value - it would be interesting to check the voltage with an oscilloscope as this would show the waveform causing this AC ... maybe this could give a hind about the source of this AC voltage.
Thanks! You know your the first person to catch that I had the probe in the wrong port. I didn’t even catch that. Guess I’ll have to try and retest again. Yeah, your not the first person to tell me I need to get a scope. Might just have to bite the bullet and get one for testing.
@@AdamDeLay07 as the cheap and the true RMS show different values, this is an indication, that the waveform is not a sinus. This is the reason why the cheap one measures correctly at the mains which is a sinus waveform
Thanks for the video, grounding is one of the hardest things to learn in solar! Can I ask what size gauge wire you’re using for grounding? I would imagine it’s eight gauge? 🖖
Grounding is essentially for safety of person. Nothing else. The theory behind grounding is that if a metal part becomes "hot" and you accidentally touched it, then it is expected that most of the current will not flow thru your body to ground but would flow via the ground wire/earthing conductor to earth. Taking the path of least resistance.
In my case there was no buzz, but i was feelinig it. Definitely not pleasant. Makes me wonder though why in my case it was stronger, but I do have a 240v mpp solar, so the voltage is probably higher.
That’s provably it. I know a friend of mine had one array that had a mix of panels between the two inverters. They were all bonded together using the mounting hardware but not grounded. He got a really good jolt when he touched his. Said he never felt anything like it. Had to be due to the fact that a part of the array was going to one inverter and the other part was going to the other inverter. Double whammy.
I learned something new today thanks! Having followed your journey, would you recommend a similar 2x EG4 6500ex for a home system or is there a better available option today for maybe a little more money? The two 6500exs would meet my split phase power needs.
I do know that Signature Solar is supposed to be coming out with a new inverter which on paper looks to be very close to a Sol-Ark, but at a cheaper price point. I'm curious to see how that one performs, but I've only seen info on paper, no real-world tests so far. I will add that I've had issues getting answers from Signature Solar support. So you might want to weigh that in with your cost based on who you decide to go with.
Use the Klein and check the Hz of the ungrounded panel. Obviously you have AC current, but at what hertz? A reduced hertz might explain why the craftsman fails to pickup the full voltage.
when inverter is closed it still feeds the coils .. ****capacitors with charge or i m wrong \?????? btw is your solid copper cable a welder cable too ? cause i saw em as welder cables in marketplace!!! maybe soldering ones have more particles to help proccess and i m not aware of that information
I don’t understand what you’re asking regarding ”the inverter being closed.” The copper wire is just a solid copper wire. Welding cable is fine stranded wire.
Hmm. Mike Holt has a channel about grounding. Very important. Anything earth grounded should be bonded.... All ground rods should be bonded, is what I'm trying to say. Could get deadly if you become part of that bind naturally.
The trouble is grounding may not work. Ground is not always zero potential. I have installed many systems including wooden frames and have never seen this potential . Of course you earth,grounding the metal frame may help with indirect strikes. As others have said this potentail you are getting is induced AC comming from a switched mode charge controller.
People are worried about grounding their panels because they think it will make a lightning rod and attract lightning. That's not how that works. The grounding will get rid of the lightning so it doesn't build up in the frame and start a fire. If you have a good grounding system, you will get rid of the lightning fast, and there will be no fire or damage to your equiptment.
@@azwelke2638 the grounding system and a lightning protection systems are actually two separate systems. From my understanding a grounding/earthing system isn’t designed to handle lightning strikes.
When you tie all of your grounds together in the panel, and then you tie them to a ground rod. That ground rod gets rid of lightning. And the bigger the ground rod, and the bigger, the conductor going to the ground rod, the more lightning it will get rid of and the faster it will get rid of it. They do make surge suppressors, but that's only because people have bad grounding systems for their house. The new electrical code requires two ground rods, at least 6 feet apart and then you would ground all of the frames of everything metal that you bring power to. It might not be mandatory to ground the frame because a lot of people do use these on RVs. But if they are on your house, where are you actually have a ground rod, I would ground the frame. It cannot hurt it. Tying the frame to the grounding system will only help get rid of lightning. And it would help your breakers trip. If you were to accidentally run a live wire up against the frame like an extension cord. If the frame wasn't grounded, the extension cord could energize it. If it's grounded, it will trip the breaker.
@@azwelke2638 the ground rod may help but it’s not a part of a lightning protection system. That’s a completely separate system. SPDs are designed to handle any possible surges that may come across the lines into the home. diysolarforum.com/threads/lightning-protection-grounding.86068/ diysolarforum.com/threads/extra-auxilary-grounding-rods-dont-do-it.81027/page-2#post-1042745
What about checking if there’s a ground and neutral bond in the inverter or your main panel. It might be ghost voltage and may be the reason for cheaper meters not getting a correct reading. Testing a light bulb between the panel and ground if it comes on it’s real electricity. If it does come on then it’s ghost voltage. My guess by the way. And thanks for the great vids.
Thanks for the comment! So the main panel did have a ground neutral bond but the inverter didn't. It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
If you look at your buss bars inside your panels you will see they do not connect in any way with the metal frames not sure where your static voltage is coming from. My panels are also mounted on wood frames and
Thanks, yes I'm aware that there's no direct connection. It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
This is very troubling to me. I had previously heard of such a problem, but it had been traced back to faulty Victron charge controller which was back-feeding the panels from the batteries. I read the comments and some of the explanations are very confusing to me because I'm not an electrician. My basic question is, is such a charge on the solar panel frames normal?
I'm no electrician either, so I have to go by what I hear. Apparently its more of an issue with cheaper High Frequency inverters (like the 6500) that don't have built in isolation between the PV and AC. This guys a whole lot smarter than me. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/post-707937
I'm using my 6500 for home backup, but plan to add some PV. I did some measurements from the black and red PV1 input cables to gnd, and to each other using my Fluke meter. I don't think this is high frequency AC. I measured 230V from red to gnd, 190V from black to gnd and 40V between red and black. This is with the Fluke set to EITHER AC or DC. It appears that the path is very low impedance, so I can't just ground the black PV input lead, and I can't connect the ground lead from my Tektronix scope to either lead to look at the signal. I ordered a handheld battery operated scope so that I can investigate further.
Are you testing this with the panel connected to your inverter? Here's what I've found by someone a whole lot smarter than me on the topic: diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
I scoped the PV input leads to ground and found that I have a 430Vp-p square wave at 60 Hz on the black lead, and 470Vp-p square wave on the red lead. These are clean, well defined square waves. Is this normal?
@@AdamDeLay07 Thanks for the link. I will definitely weigh in on this. I also contacted Signature Solar about this and will contact EG4. There should be a warning in the manual. I think a lot of people probably assume that the PV input, being an input and not an output, would be safe to touch. I got shocked while wiring my PV disconnect breaker. It could easily be lethal. You can draw a LOT of current between either PV input lead and ground.
I was thinking about this today and now I'm wondering if your Victron gear does this too or if it's just a 6500EX oddity. Maybe a video idea for warmer times. :) I'm guessing not.
@@SolarShenanigans no worries. With the 6500s, there’s little to no isolation between the PV and the AC H Bridge. That’s why there’s AC power bleeding on the frames.
i was getting 70VAC @ 144 MHZ on my 8 x 340 watts array until i grounded it, your getting maybe 20 milliamps but it still give you a zap, doubt its dangerous but uncomfortable to the touch !
Voltage tests need to be done with a load connected. Most meters don't have enough internal impedance to create a load. A Knopp type voltage tester provides a load so it would provide a more accurate voltage measurement. Even in your vehicle... if you place your meter across the battery you'll read approximately 12.7 vdc. Now turn on your headlights and you will get a more accurate measurement of the state of the battery. Yes the voltage will drop some. Now crank the starter and you really check the capacity of the battery!
It is a little unsettling, but would it start a fire or kill someone? Is your neutral bond disengaged in the inverter? Most of mine are in wooden frames and ungrounded. I am running two different systems though - 1600 watts feeding a Bluetti AC 200 max going to a transfer switch, and a 12 volt 2000 watt system with a LiFePO4 12 volt being fed by 400 watts to a 30 amp PWM controller. I have wondered about this before, I guess I will check it now. I know you said the voltage was not being compounded by the wood screws and fender washers, but that should bond those panels together allowing for just one grounding point. It could be done with spring loaded clamps and cable incase you have to move the panels occasionally.
Really hard to say. I mentioned that @Gavin Stone was hit pretty hard when he was working on his LV6548 arrays. It seems to all be related to the cheaper HF inverters that don't have isolation between their PV and AC. There didn't seem to be an actual pattern of X panels = X volts. I had thought there was initially, but was still getting 70 with the 1 panel as opposed to 140 with 6. Doesn't make much sense to me.
@@AdamDeLay07 Thanks for the video and the reply. I will investigate my stuff and keep it in mind if I upgrade to a hybrid system. I'm building my 12 volt system 1 battery at a time with the intent of jumping up to a 48 volt system, but there always seem to be issues with EG4 stuff. Is the neutral-ground bond disconnected in your inverters?
@@PWoods-cd6tk Not a problem. That's how I started. In fact, I'm looking to repurpose my old 12v system shortly into a portable power station. Good luck! Yes, the bond screws are removed in both my inverters. The only N/G bond in my environment is in my MSP.
Depending on the inverter used is the grounding of it,, EG4 will send charge back to panels,, dnt like it so it may be the issue ,, try measuring the voltage on the receptacle of the mppt side without panels...
If I recall, I did check that when I was upgrading my PV connections and I thought I was getting 35v directly from the terminals without any PV connection.
How on earth can that happen? The frame should be completely isolated from the cells and internal buss connectors. The glass and silicone layers should insulate all electronics. Is there something that Renogy is not telling us about their panels or did this happen with all of your panel brands? Something I am missing?
It turns out that the cheaper all in one inverters (like the eg4 6500 and the MPP lv6548) have some issue with their H-bus and isolation. It allows AC to somehow bleed on to the PV frames. I don’t understand much of it myself but I’ve had much smarter people than me try to explain it. It’s over my head. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937 It’s not specific to the Renogy panels, because it happens on my SolarEdge panels as well. It all goes back to the AIO inverters. Ultimately it reinforces the need to make sure you earth ground your panel frames.
@@AdamDeLay07 Wow! Crazy. I have not checked my new array but the old one is on that big metal frame from Powers Solar Frames. I may check just out of curiosity.
@@CountryLivingExperience yeah just pick one panel that’s connected to your 6500s and disconnect the ground. Then measure the AC voltage between the panel frame and the ground wire. It’s been a while, so I can’t remember if I found out that you had to have AC In connected to the inverter for the voltage to show up. I know I’ve heard of others with this issue on both EG4 6500s as well as the LV6548s. I’ll be interested to hear what you find out.
Assume we have straight dc panels no micro inverters etc . What voltage is on the panels frames ? Coming from where ? Induced? Since there is no conventional trip protection for dc to detect leak What does earthing do for you ?
You can see the voltage in the video. It’s coming from the inverters. It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
Personally, I don't get it either but it turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
@@AdamDeLay07 yes but all of my solar panels do not have an electrical connection to either the positive or negative leads. The panel is suspended by glass.
@@RICHIE26636 correct, all panels should have an air gap between the panel and the frame. Like I said, I still can’t explain exactly how it’s happening at the panel, but it is coming from the inverters. Not being an electrical/electronic expert, I really can’t explain other than what’s been told to me by people much smarter than me.
air friction creates static. you can take a bare copper wire and set it vertically in the air and it will produce voltage. the higher the wire the more the voltage. main reason they run lines in the air, that static helps boost the grid
Hahah. That's funny, but not true. Transmission lines are in the air because air is a great insulator. If one were to try to bury the lines instead, the cost of doing so becomes enormous because massive amounts of extra insulation would be required. Transmission lines are HIGH up in the air because they are energized from tens to hundreds to even a million volts, and that energy can easily couple into anything nearby. Since ground is basically ground, such coupling can be catastrophic. So the lines are high up in the air... and even so you can still feel the electricity in the air when you walk under a high tension line. There is a voltage differential in the air that goes up with height, and the voltage itself can be quite significant. But the amount of current you can draw from it is miniscule because you more or less instantly deplete the electrons in the air next to the wire (wind or not). i.e. the voltage differential will disappear when you try to suck energy out of the wire. Static electricity from air friction is an equal opportunity employer. It isn't generally all that much energy in the first place, and it applies equally to all the wires in the transmission line so it does not create any sort of voltage differential that could be harnessed.
@@junkerzn7312 you are just repeating what you were told by another that has no clue. all you have to do if go read about other things and put it together but you wont , it requires reading lot of it and ohh yeah, the ability to comprehend
I was going to suggest a drill stop. I had to drill out the holes on all the panels of the last array I installed and that's how I did it. But the step drill would work too.
It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
I Earth Grounded each of my SIX (6) PV Panel Arrays to an 8' long Copper Coated STEEL Ground Rod SIX ARRAYS = 36 Panels SIX Ground Clamps on ONE Ground Rod in a 6S / 6P Configuration to a ECO-WORTHY Six (6) String Combiner--Box equipped with a SURGE-Protector circuit = one >MORE 6-AWG Bare Copper ground wire = SEVEN (7) Direct-Bury Ground Clamps on that ground rod ... in total ... COOP
Buzzing is from static charge possibly thousands of volts, very little amperage, that’s why it’s not zapping you. Caused Most likely from the wind passing over your panels. This is not from a/c. You seem to have some a/c voltage,most likely from your inverter but likely is fantom voltage with no real amperage. A small wire from your panels to ground will dissipate this type of voltage. Earth grounding will not dissipate and zero out a/c voltage. If you have true a/c voltage with small or large amperage it will continue to flow on the wire even if earth grounded. Electricity does not only follow the path of least resistance, it follows ALL paths. This is why we use grounding not earthing. Very confusing but it is very important to know the difference.
If you are measuring AC voltage on the solar panels, this is a feedback from inverter. You better test your inverter, most of them high freq are floating.
Thanks for the comment. It actually turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
25 volts would not have been enough to create that buzzing. Your meter isn't reading it accurately. Edit: as you saw by using the other meters. I also question their accuracy... you really need peak voltage, and the best those meters might give you is true-RMS - an average. In any case tho, the current is minimal, nothing to worry about other than a possible surprise.
It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
If you're interested in learning more about earth grounding your panels, I found this resource on the diy solar forum to be extremely helpful! FilterGuy does a great job explaining things for even someone like me to understand!
diysolarforum.com/resources/grounding-made-simpler-part-3-solar-panels.160/
Once again Adam out-of-the-park keep up the good work we really appreciate your efforts
@@JOHNDANIEL1 all I know is I got shocked like no tomorrow grabbing the handle to my shed and if running a ground lug to my house grounding rod stops that then I’m all about not getting shocked!
@@JOHNDANIEL1 it’s the poor isolation of PV from the AC of the all in one inverters it’s “AC power” that’s the shocker checked that with a meter not “ DC “it’s a known problem with many of the HF all in one inverters from what I understand. So the ground is to dissipate the AC back current off the frames.
Back feed voltage in screted on serface of pv wire but tested on frame ?
No. Its nothing to do with cheap inverters its the design. The pv bus is switched twice per mains cycle to the neutral with alternative polarity. That basically means the panel potential moves up and down hundreds of volts as it switches with respect to earth because it is usually tied to neutral. That is not a problem because your pv voltage will kill you anyway. So why does the frame feel live? Its because it is capacitively coupling to the panel. Think of the pv cells as one plate and the frame as the other plate of a very small capacitor. Because the capacitance is tiny the AC current that flows is tiny. You can measure 50 to 150v with a suitable meter. If you ground the panels then you will no longer feel this. Does it matter? Not really. But the switching potential on the frames does emit radio interference and so grounding it reduces that a lot. But its nothing to do with cheap inverters its just an efficient way to do it and galvanic isolation will just introduce more loss.
I can definitely attest to the need for earth grounding. Especially with a wooden rack system! Thanks for making this.
Thanks for sharing, Adam. Your method for identifying electro potential on your panels are unorthodox but effective. Be safe.
Awesome video and purfect example of why grounding the frame is important. Cracks me up on other channels complaining about voltage and inverters are unsafe bla bla bla but they dont have the system complete🤷♂️ Great job Subscribed💥🤘
Thanks a lot Joe!
Adam, as it was mentioned here already most likely what you see is High Frequency AC coupling from MPPT charger (built in 6500x). It's not 60Hz AC coupling/leakage from the inverter part of 6500x.... That explains why you see what you see... Most of the cheap meter won't show properly 100kHz frequencies. You better use a cheap oscilloscope for that. I won't be surprised if you also use a multimeter with LoZ setting and it will read almost nothing. I think I saw similar things with my 6500x when I was trying to put an EMI/RFI filter right at the PV input. That thing (it's internal MPPT in particular) emits quite a lot of interference on HF frequencies (Short waves) into the air :( It's all about internal circuit design. Grounding the frame is possibly the easiest thing to "deal" with this issues. It still will be coupling that 20-100kHz but you won't feel or see it :) Coupling is happening between PV cells and the frame... That structure forms sort of a capacitor.
This comment should be higher. This is a great explanation of why this fix should not be scaled or generalized as proper earth grounding
No more shocks is a good thing, appreciate you posting this 👍
Make sure the bare copper is not touching the aluminum frame. The copper and aluminum are dissimilar metals and with bare contact will cause corrosion. It’ll eventually eat into your aluminum.
Great reminder! I'll make Ian crawl through and make sure nothing's touching. Thanks!
Good point about the galvanic corrosion. That will happen to the clamps over time, assuming they aren't anodized. Or even with Aluminum and a stainless screw on the clamp.
But the ground wire is copper and it's grounded to the aluminum frame ?
@@thedampestcrib6004 have to use appropriate connectors otherwise corrosion will occur.
You can add anti oxidation grease for copper to aluminun joints
Thanks for the video. I am dealing with a lot of the same issues. I have two EG4-6500ex-48 and I am getting voltage on my racking and buzzing when I touch the panels frame. Also got low reading in the 40V ac with my cheap meter and 140v ac with my nicer fluke meter. 1 st world problems I know but it sure is frustrating. I have spent a good portion of my life listening to Signature Solar’s hold music.
Thanks. Sorry to hear your having issues. I spent a lot of time on hold too.
Thanks for vid. Newest NEC codes say panels/mounting need to be grounded. I think in the past some people considered it optional and only as a means of lightning protection or something. NEC 690.41
Regarding the craftsman meter. It depends on the input resistance of the meter. I have a high end fluke that is very sensitive. It reads 200 volts AC o the PV lines but my cheaper Chinese meter reads about half that.
The difference in your meters' voltage readings probably has to do with the meter input impedance. The source of the AC voltage you were detecting is capacitive coupling to the back-fed AC power. This normally is a very high impedance source so very little current in available. A high input impedance meter will register a higher voltage than a lower impedance (cheaper) meter because the lower impedance loads the source & pulls the voltage lower. It would be interesting to check the current drawn by each voltmeter to verify the actual power (volts x amps) involved. The charge you have detected is unlikely to be dangerous, but in the event of insulation failure (conductive voltage back-fed), it could become lethal. That's the whole reason for safety grounds in appliances: the internal voltage may energize the appliance chassis (outer case) in the event of internal insulation failure & should you touch a grounding source & the appliance case you become the conductor of lethal currents. Modern standards allow double insulation in place of a safety ground connection to the case. There is also value in grounding the panel frame if lighting frequently happens during storms in your area. The safety ground could prevent the lighting current from being routed into your home over the power leads by diverting it at the panels.
HOWdy A-D-L, ...
Thanks - this is one of the 1st things that I did on each of my SIX (6) Arrays ...
Grounding LUGS + 6-AWG Bare Copper Wire ...
into my ECO-WORTHY Six String Combiner-Box ...
36 PV Panels = run in a 6S / 6P configuration ...
COOP ...
the WiSeNhEiMeR from Richmond, INDIANA ...
...
Good morning Adam
With my system I think I’d be fine because I’m using sign post which are metal and they are into the ground at the bottum
Update on my new growatt 3 5KW System. Such a great setup. Don’t get me wrong I’ve had a few codes but nothing like the pile of garbage I had with the 2 EG4 6kw inverters
And the flickering is pretty much gone
And I’m running my whole house. Air compressor jacuzzi tub washer dryer and all the normal stuff
Super happy with my change in the system. Have fun Adam and keep up the great solar videos coming 👍🏼
Glad to hear after so long of you having issues, your finally able to just use a system and almost forget about it because it just works! Thanks for sharing!
Ideally your panels should all be ground at only the single ground your house/main uses.
@@ssoffshore5111 correct. That’s what NEC states as well.
I just occurred to me I have a single ungrounded 435W panel setting on pavement against the house with an Enphase micro inverter on it, I've never noticed any potential on the frame, even when wet. I'll have to test it now that you reminded me!
Enphase inverters are grounded internally to the chassis through the green wire in the 240vac trunk line. The instructions for Enphase clearly state no external ground required. I have 36 of them and no external ground. I passed inspection.
Really good and informative video I have voltage ony panels on a wooden frame so my next job will be to ground my panels
This is a great finding sir.. Thank you so much..
Really wonderful video I was looking for these video since because I was having these same issue thanks I really appreciate for the help
A great video …. Had the same issue my limited understanding is due to transformer less inverters get capacitance leakage on the dc lines from the ac. I was getting about 30v to earth on mine from a Growatt 5000es. There are specific washers and plates that cut into the anodising to further help get that stray current ground. I got ac and dc current on the panels also
Hopefully you got yours taken care of as well.
@@AdamDeLay07 I did thanks just make sure the earth conductor is bigger than the solar cable ( the advice I was given )
you get the same effect with a bench PC . if your disconnect the earth wire so the PV power supply is floating, you will get some shocks, like static electric cos of the way the switch mode power supply (ATX) works, its a capacitive coupling - annoying getting zapped.
Thanks for the video, ....
What a Nice Dog You Have ....
Thank You
Thanks! She's a big baby!
Most installers appear to just ground the aluminum racks, not each panel. When I worked at Edwards AFB, CA, you soon learn to touch a water fountain with your knuckles. A spark would jump 1/4" thru the air. Ditto when I lived near Chicago in winter, in a building with no humidifier. That little buzz is nothing. Likely from current leakage thru the inverter. But, smart to ground the frame in case the inverter shorts grid-power to the frame via the solar cells.
When I was installing a ground washer was placed between the panel and the frame that digs into the metal of both panel and rack which was per code but I still put a ground lug on each panel anyway. The ground was hooked to the rack then each panel down the line. Haven't noticed much if any corrosion between stainless set screw lead alloy ground lug and copper ground wire but I live in the desert so not so much moisture
I figured it would get absorbed by the battery and by the capacitors in the charge controllers. But I guess not. Wow. New information.... that's why I like your channel!
I would posit that the power factor of your AC loads would also have a significant effect on the ripple you are seeing on the frames, since poorer power factor directly feeds-back through the inverter to the DC side.
Appreciate that!
Hard to say. I’ve found most things with a poor PF cause my lights to go nuts in the house. I’ve only found 3 things in the house with poor enough PF to flash the lights.
Remember the frame of your panels are actually isolated from the +ve and -ve of you input.
@@eddietee6305 The issue being talked about here is a more indirect path where some of the AC couples back into the DC wires. There are three ways this can happen.
* The first is direct coupling backwards through the AC inverter... it ends up looking like ripple on the DC side.
* The second is direct coupling backwards through the AC inverter due to reverse current due to a poor power factor. Basically, when there is a poor power factor on the AC side, some of the energy will actually couple back through to the DC side. In large inverters this energy is mostly captured by capacitors and re-fed back into the inverter. In cheap inverters this energy just couples back to the DC side and ends up as stronger ripple on the DC side.
* The third way is through EM radiation. Any AC waveform radiates energy. The energy will couple into any wires in proximity to that EM radiation (regardless of insulation). That is how AC winds up on the frame.
We see similar issues crop up with AC breakers, for example. If you turn off an AC breaker and there is no load on its output grounding it, i.e. the output is open, you will measure significant AC on the output even though the breaker is open. Usually somewhere around 50-80VAC. Very little current can couple through, but it is certainly enough to give you a shock. The effect is even more pronounced with a contactor or relay... sometimes enough energy couples through that LED lights will continue to flicker or light dimly even though the switch / relay / contactor / breaker is "off".
So that is how we wind up with AC on the solar panel's frame... and it is indeed often enough voltage to give someone a significant buzz. Grounding the frame fixes the problem. But determining the best place that the frame should be grounded to is actually a really difficult problem for a multitude of reasons. i.e. should it be to a nearby house ground wire from a plug? Do you have to run a ground wire all the way to the house grounding rod or main service breaker box? Do you need to sink another grounding rod into the ground near the house? There is no right answer.
This panel can put out close to 100 watts ruclips.net/user/postUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.
Not sure I follow what your talking about
Shocking 😅. Great video
I read somewhere guy had an EG-4 6500 his utility called him said he was back feeding turned out the inverter was back feeding through the input side on a off-grid inverter. The panel not the only place it back feeds voltage. One reason I went with a Sol-Ark If your off grid don't want to spend the extra money have to work around their issues like you pointed out you can save the money.
That’s very interesting. Never heard of that before. Can you share the article you read?
@@AdamDeLay07 I'll look around might have been on DIY forum can't find it now I'll keep looking or could have been a YT comment on a video review of the 6500.
Good Video much to consider...
On a side note: I don't know if this will someday go national, but Insurance companies in "our" area are starting to cancel home policies that have more than 10k of solar panels attached to their roofs. The risk of fire is very high if not installed correctly.
It's a catch 22 for people who don't have a lot of property to put the panels on the ground...
Thanks for sharing. Defiantly something to be aware of.
That would apply in South Florida, for one.
I used a short piece of cpvc 1/2” pipe as a drill stop.
I use battery jumper cable gutter spike for grounding my motor home , clip on bumper clip to spike , works good
Interesting. I also have wooden frame ground mounts. I grounded mine during installation as required by the NEC. I drove an auxiliary ground rod at the panels and also bonded them back to my service panel. I haven't noticed anything when I've touched the panels, probably because of earth grounding and bonding. I'm using the EG4 6500 inverters as well. I'll have to check for voltage from panels to ground. I'm surprised there is any voltage at all with a grounded panel system.
Yeah apparently the cheaper HF inverters don’t have any isolation between the PV and AC. At least that’s what I’ve heard from people who know a whole lot more about this stuff that I do.
@@AdamDeLay07 Yes, that's correct. Or more specifically, they don't have high quality energy recovery from the AC that couples back through the transformer, or any shielding from the EM.
I'm not sure whether you are allowed to ground to both location at the same time when the grounding rods are really far apart. At a minimum, see if there is a significant DC voltage differential at the house between the ground wire coming in from the array (while disconnected from house ground), and the house ground.
Having a really long ground wire going across the field could increase the damage that nearby lightning causes by giving it a low impedance path into the house, which might not otherwise occur.
@@junkerzn7312 This is a great topic for conversation. First NEC 690.47B does allow for and additional ground rod at the panels, in fact in that same section, "the support structure for a ground mounted PV array shall be considered a grounding electrode", ground mount system grounds are addressed. To me a steel ground mount racking system really can't be isolated from acting as a grounding electrode. A wooden one probably can, so long as it's not damp or wet. I've watched Mike Holt's videos who would agree with your scenario. I would also agree if either one of the DC power carrying electrodes was grounded, or there were no grounding conductors between the array and building service panel. Something to consider too, would be a direct lightning strike to the array. I understand that no system would protect sufficiently for a direct strike, I do believe that a greater part of that energy would go directly to the earth ground at the panel and may in fact reduce damages to the system in the building. On my system, I used #4 solid copper to ground my array to the auxiliary ground rod, and #8 stranded to bond to the building service. As I started out saying, this is a wonderful topic for discussion.
@@backtothepast1850 Yes, total agreement. There is very little real-world data supporting one scheme verses another. The distance is going to matter a lot, too.
I have a main system on the garage roof which is right next to the service ingress. The grounding for that is obvious. But I also have a bunch of panels hanging off the back deck on the entire other side of the property, 200+ feet away. At the moment I have that tied into a simple house circuit's ground but I just don't know if that is the best solution.
For a remote array in a field, I'm more partial to grounding at the array since it is already partially grounded there anyway, but not feeding a ground wire all the way back to the house. Instead, I'd have surge protection at the house for PV- and PV+ tied to house ground. The idea being to protect the house systems as much as possible from damage. In that case I think sinking a second ground rod AT the house and tying it into the house ground (if the main rod is on the wrong side of the house for example) might be reasonable.
But I just don't know. Really just my ruminations as an EE. But an EE is not usually a certified electrician.
check the same when turning off the inverter output but with solar still charging the battery's. probable same thing i experienced with voltronic inverters (same inverter builds, different color and branding). they seem to put ac back trough the solar input only when the inverter is making AC power. also got shocked by them when was installing metal sheet finishing around a metal roof with panels installed on the metal roof.
Thanks I got a Growatt 5kw I felt that voltage one day and my panels are also mounted of wooden structure
It’s surprising how many people I’ve heard have felt the voltage on their frames. Apparently on cheaper HF inverters, there’s no isolation between PV and AC. You would think there would be on all inverters.
@@AdamDeLay07 we all love high end Inverters but they come at a premium price, My Growatt works great two issues I have with it high idle consumption and what we just spoke about otherwise I got Power
@@Theoppositeofchaos Exactly. I've got little quirks here and there, but nothing that's really preventing me from powering my house.
voltage differences on different meters could be due to induced voltages from AC back feeding?
Any brand of 6548 is non isolated, then they back feed the solar array with AC through the mmpt input
I have an eg6500ex split phase system and I can measure 200 VAC on either of the PV connectors and I can feel some electrical charge on the frame although I did not measure. it. I also have a wood racking.
Crazy! I never expected that till I heard the buzzing on mine. Better ground those puppies…
Oh wow you could hear that, wild.
Slip a piece of plywood between frame and panel to prevent the drill bit from damaging the back of the panel.
Impressive. Between the isolation in the inverter and floating the output. Yeah they're supposed to be grounded for a reason. They're metal objects and they can become live so you want them grounded to Earth potential in case there's anything wrong with the equipment or if a wire accidentally comes in contact.
I found the shocking aspect when the panels were wet. I was curious as well and after testing I thought the ac voltage on the panels was due to the solar cells producing power. I disconnected the panels from the eg46500 inverter as you did and found a small voltage still exists but then I added a small resistance load to the panels +- to get the panels producing current and the frame voltage when up so I assumed the frame voltage was a by product of the panels producing power. I would like your feedback on your thoughts.
Yeah once I discovered the “voltage leak” for lack of a better term, I avoided the panels when it was wet outside.
Unfortunate I’m not super familiar with the underlying workings of solar panels. In your isolation test though, I’m assuming any voltage you saw on the frame would have been DC, correct?
I guess either way it really emphasizes the need for grounding!
I have never seen that with my two 12K home system. Started up my two shop 6500EX’s….same bs before grounding. A little scary at first. I guess we get what we pay for. I didn’t even have both pos and neg leads hooked up to the panel.
It’s just crazy!
Crazy find. I remember a rather large RUclipsr claiming the EG4s didn't have this problem.
Had to go back trough to find those comments. Looks like he was testing at the PV inputs of the inverters. Not exactly sure how he tested because it wasn’t mentioned, but he said his tests revealed “20VDC and 0VAC”.
Because it's not necessarily an inverter problem, it's an end user design problem. These should have been earth grounded from the beginning. This is a common problem in the DIY community. People think they can cut corners and save money, this is the result. There should be no AC voltage at your racks. I would bet he has AC/DC grounds mixed at some point. There should be no way AC voltage is present on your panel racks.
@@AdamDeLay07 I'm glad you've brought this to our attention. I'm going to hook up the 48V 3000TL LVM by rich solar in my trailer this season. I will have to test my array. I used the MidNite Solar MNDC-GFP63 in my diy combiner box.
@@Scotty2Balls I had it on my array. I’ve talked with 3 others that have had it on their array. How would someone mix the ac and dc lines?
@@Scotty2Balls Code in Canada
64-222 Photovoltaic module bonding (see Appendix B)
1) Exposed, non-current-carrying metal parts of photovoltaic modules shall be bonded to ground.
2) Module bonding connections shall be as specified in the module installation manual.
Δ 3) Notwithstanding Subrule 2), bonding connectors intended for bonding photovoltaic modules and
installed in accordance with the manufacturer’s instructions shall be permitted to be used.
4) The connections to a photovoltaic module shall be arranged so that removal of a photovoltaic
module from a photovoltaic source circuit does not interrupt a bonding conductor to other
photovoltaic source equipment.
S
good video and comments from it. Ive also seen other videos that say not to earth panels as this will attract lightning! ???
Thanks. Yeah I won’t even begin to understand how it all works. I do know that lightening protection is a completely separate system from normal “earthing” though.
@@AdamDeLay07 Think it would be best to earth the panels or anything that mixes metals and electricity. But also put in a higher lighting conductor. As you say , these are two different issues.
I got shocked pretty good today by my shed and I know understand why “earth grounding” the all in one are necessary! My question is did you run your wire back to your service panel grounding or directly to the house grounding rod outside? Would love to see that part! Thanks so much for the videos!!!!
I believe I saw your thread on the forum. It's not pleasant at all...
From everything I've seen, it should be run back to the main grounding conductor of the structure. When I set it up though, I had it on it's own ground rod.
Can't say I fully understand it, but I can tell you I don't get shocked after earth grounding the frames. From what I've read though, the cheaper HF inverters tend to have little to no isolation between the PV and AC H-Bus.
If you put another rod in, it will create a ground loop between the two rod locations. These also won't connect the two locations (home/building/inverters) to panels thus they'll have different charge levels and can still shock you.
The other issue is the "loop" issue which if lightning hits it'll pass through your equipment and loop back through the rod. This doesn't happen if you have 1 centralized location to go to into the actual earth-ground
Which is why it should just be ran back to the house and then attached to the breaker box ground or somewhere there
The Kline is likely an RMS meter. And get those MC4 connectors off of the ground. Check out my wooden rack that I just built. It goes to a DC assist heat pump.
It’s an RMS meter
Great video, and I like your discovery process.
I do have a question: aside from static charge and induced current from nearby lightning strikes (or other nearby high frequency EM fields) there shouldn't be any voltage buildup between the panels and ground, and once you've discharged it, there shouldn't be any substantial voltage potential left.
So why is it that your system shows a persisting voltage difference?
I'm not an expert, but logically there has to be a continuous source of energy "charging" your panels' frames.
I can think of two options:
1) Internal: there's some kind of "leak" in your system.
2) External: there's some kind of external source of energy, e.g.- a persisting EM field, strong enough and close enough to induce current in the metal parts of your panels.
The first reason seems a lot more likely.
If you find the reason for this, (and the solution:) please share it with the rest of us.
Thanks
Thanks!
Your exactly right, there shouldn’t be anything there. After more research, it actually looks to be a fairly common problem with cheaper AIO inverters (I always say there has to be some compromise getting all the components in the AIO inverters to play nice together).
So it seems there’s limited to no isolation between the PV and AC H-bus, which then allows AC Ripple back to the panels. I still don’t understand how voltage shows up on the frames when they’re not connected to the pv lines at all, but I know it’s happening. I trust people a lot smarter than me for the explanations.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
Did you try measuring it with a Low Impedance Meter.?
Most meters are High Impedance. If you stuff up, a High Impedance meter will conduct less short circuit current making them a little bit safer than a Low Impedance Meter.
However, a High Impedance meter will give you inaccurate readings of 'Ghost' or 'Phantom' Voltages from Capacitive Coupling and sometimes from Inductance.
Switch Mode Power Supplies and Inverters, which both have high frequency switching creating some coupling, and some the cheaper versions have a capacitor coupling the (relative) low voltage and extra low voltage sides of the switching units. Some can also contain Noise Filters between the LV and ELV circuits also.
Thanks for the info. No I didn't try with a Low Impedance Meter.
Adam, one note, you mentioned grounding the panels on the shed roof for protection in case it gets hit by lightning but earth grounding is not for protection against direct lightning strikes. I recommend watching Mike Holts video on grounding and bonding where he does a wonderful job explaining the difference and purpose of the two. You are correct that earth grounding allows for dissipation of any static buildup or electrical surges due to "nearby" lightning strikes.
Thanks. Yeah, in the beginning that was how I thought things were supposed to work (of course little did I know).
I'm gonna trim that comment out of the video to avoid any confusion, because it obviously isn't the reason to ground the panels. I really appreciate you pointing that out!
@@AdamDeLay07 haha dude I had the same issue and I spent countless hours searching and watching youtube videos trying to understand the purpose of grounding and bonding. Mike Holts videos are the best reference that I found for understanding the purpose of both and to understand the best code compliant techniques for wiring
I followed Mike Holtz explaining earth grounding of solar panels and bonding the ground of the system. I have 12 panels on an adjustable wooden ground mount. I have none of your issues with AC voltage back feeding the panels. In his series he definitely suggests not earth grounding solar panel arrays or generators. He does however suggest earth grounding the inverters and bonding all components including the transfer switch if used. This is a separate grounding rod specifically for the solar system and all components. I also installed EMP SHEILD units on my main grid 200 amp panel. The 2 inverters and my batteries.
My system has worked flawlessly for about one year now and my panels are not earth grounded.
Perhaps you have not grounded your system properly causing the back feeding to your panels.
Please check out Mike Holtz and his series on grounding and and bonding. His expertise is used in court cases and has been documented many times.
Personally I don't think your problem is with earth grounding your panels. I think it's with the way you earth grounded your system.
Good luck and I hope this helps.
Sorry but I have to disagree with your statement. A separate roof mounted lightning rod ,or rods hooked to a earth grounding rod will dissipate a lightning strike.
A grounding rod for an electrical system can actually attract a lightning strike. As will a metal light pole, flagpole, basketball goal, etcetera. Including your roof mounted and ground mounted solar panels or backup generator. Check out Mike Holtz!
It might be interesting to test the current to ground from the panels to see how much power is going through. Also something that is confusing me, if the inverters are in fact injecting AC power to the solar panels how is it showing up on the frames? Every panel I have tested there is no continuity from either the positive or negative wires to the frame. ???
When I looked, the current barely even registered on the meter, so that's why I barely feel anything when I touch the panels.
Unfortunately I don't understand how it's all happening either. Someone much smarter than me told me (and I'm gonna try and remember exactly what he said) that "in cheaper HF inverters, there's no isolation between the AC and PV." Because there's no isolation, you really wana make sure to earth ground the panels to dissipate any leakage.
This might help a little bit: diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
So interesting that many of us have the same inverter clones but varying issues. This made me curious. I have an SP6548 that has been giving me issues with flickering from day one. It too had ac voltage on the frames of my ground array before I grounded them. I borrowed aMPP LV6548 that I hooked up yesterday and 0 flickering lights. This video made me want to check the panels. Just pulled my grounding rod and checked... 0 ac voltage on my frames. Is this voltage leakage from the units another defect? Brought up a great point, always ground your panels. Thanks for the video Adam.
Thanks! That’s interesting that you showed 0v when testing the LV6548. I’ve heard those can have a nasty zap. There has to be another common denominator. I’m wondering if it’s using AC In. Have to test to find out.
@@AdamDeLay07 Watts247 has the LV6548's on sale right now. After all the headaches and what I spent on filters, rma shipping, new bulbs, dimmers etc .. for 1k... just cutting my losses at this point. Something deff not right with these units.
@@MrMike-fn4hi current connected has some on sale as well. $910 with some caveats. ss.currentconnected.com/product/mpp-solar-lv6548-all-in-one/
Add a couple of panels to make your fence out of vertical solar panels to clean the yard up.
If I wasn't worried about things being thrown from the mower at the panels, I might actually do that! The wooden frames get the panels up high enough to keep them from being hit.
I have a eco-worthy hybrid system, it used the battery voltage and pv state to switch based on the settings you selected.
Nice! Do you like it?
@@AdamDeLay07 yes i do. I was thinking I need bigger panels. But watching your videos I realize bigger not always better.
@@djblingazworld yeah it all depends on the space you have as well as the voltage specs of your solar charge controller.
In this video, the problem was solely due to the EG4 6500. It doesn’t matter what panels you have, you would still have the same problem.
FYI: I used a 4" Grinding Wheel to remove a "patch" of ANODIZATION to BARE Aluminum where my Grounding-LUGS attached with Stainless-Steel 1/4" SAE Bolts
COOP
...
Another possible reason for the difference in meter readings is that the inexpensive meter might not take RMS measurements. So, if the AC being measured is not a sine wave then the measurement may be different. Why might it not be a sine wave? Ask the inverter :)
Saludos, solo para estar seguro de que entendí... ¿lo ideal es que el metal/aluminio no toque dos paneles a la vez y asi no hay que ponerle cable de ground? ¿O el metal/aluminio que no toque dos paneles a la vez y luego ponerle cableria de ground?
Seré honesto, no estoy exactamente seguro de cómo o por qué está sucediendo, aparte del hecho de que el inversor de alguna manera está enviando voltaje de CA de vuelta a través de las líneas fotovoltaicas. Resulta que este es un problema bastante común con los inversores de HF más baratos. He recibido bastantes respuestas de personas que usan el mismo inversor de estilo (ya sea SunGoldPower, MPP o EG4). Al mirar a través del DIY Solar Forum, parece que estos inversores más baratos no tienen un aislamiento adecuado entre el PV y el AC H-Bridge.
Https://diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
My question is this... even if the invertor is sending a signal out to the panels. How is it that the frame of the panel is connected to either the positive or negative wire of the panel. Do you show concuctivity between either of those wires and the panel frame? I'd hope not! In short.. how does ac on the wires translate into ac on the panel frame? My guess would be some kind of incuction from the panel traces closest to the frame.
I didn't see any conductivity between the panels and the frames.
I've tried to understand how it's actually happening and haven't been able to figure it out myself, but I'm not the only one experiencing this issue. It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
I guess I'll have to put the meter on it. I'm running a mpp solar lv2424 but will be going to 2x lv6548 units .
Supposedly the lv6548 is worse.
@@AdamDeLay07 uhg
@@natesdiysolar So after talking with someone who had 2 lv6548s that got bit with the voltage on his panel frames, we came to the conclusion that he might have had strings from 2 different inverters on the same array, and they were being electrically connected by the washers holding the panels down. That would increase the voltage on the frames. Just FYI.
When drilling the hole larger simply cut a piece of pipe or emt that the drill bit can fit through.. this keeps the bit from over penetrating.
Thanks for the tip! Never thought of that one!
Very interesting discussion. I have two LV6548 and...
6:05 He's not the only one that got popped, don't ask haha
12:19 I'm seeing around 90V on mine with a Fluke
14:21 I'm no engineer but I suspect that, while there is voltage, it's just leakage current (very, very small amount). Perhaps the Craftsman has lesser resistance between the probes? Don't know, just a guess.
Thanks!
I’ve heard from several people who’ve been…”surprised”. 😁
I imagine that might be the reason the craftsman didn’t show the same info. Especially since it showed proper voltage from the grid power.
@@AdamDeLay07 Here's a fun one to add - if you have 2 inverters connected to form standard 120/240 power and you have a solar array connected to each inverter, you have nearly 200VAC between the frames of both arrays!
@@LithiumSolar it’s funny you mentioned that. I was talking to someone else that had multiple strings from multiple inverters on a single array. The strings in the array ended up being bonded together due to the mounting hardware. Got a really good zap. Said he’d never felt anything like it before!
@@AdamDeLay07 I was just wondering what putting a Ferrite filter on the PV lines would do. I'm just getting into solar and don't have the equipment yet to try myself.
I would be more concerned as to why the system is back feeding AC into the PV array.. I have a similar setup where my panels are literally on the ground or blocks, and I move them around as well and have not noticed this. Iv been thinking of grounding my panels as well. How many watts is your pv array..
Supposedly it’s common. Doesn’t make sense to me how that could be common.
I have 3 ground arrays. 1365w, 1200w and 1820.
@Adam De Lay I'll do some research once I get my lv6548s running. Wonder if it has to do wth ground neutral bond. Im thinking of off loading the charging to a Victron mppt and just using the inverters as inverters only.
@@natesdiysolar that’s an interesting thought. Wonder how the inverter consumption would change if you never use the mppt? In my case, the only time the fans work really hard is when I have a lot of Solar coming in. Even with larger loads, it doesn’t seem like the fans run that hard.
Thank you for the information. Did you use a separate grounding rod just for the panels?
They’re grounded back to my main house ground rod.
It sounds like you have a floating earth bonding issue??..might be a good idea to also check your house earth bonding as well??.. could be a issue with the big inverter earthing (by yours mains fuse board).. sounds like it's floating??
Thanks for the comment. My main ground is intact and not floating. Apparently this is a known problem with cheaper HF inverters. There’s no internal isolation between PV and AC.
Lot of people say to ground the panels to a different ground line then the houses main ground line....the panels on your roof are grounded to the main line of the house? Or do they have a different independent line?
I believe code states that it's all supposed to be going back to the main house line. Here's one of several videos that have helped me "understand" the confusion that is the codebook...
ruclips.net/video/cZo8ict33_I/видео.html
a small note about your measurement on 8:17 - the black wire should have been plugged in on the com terminal for VAC measurements!
Concerning the measurement difference on 13:20 - this might have to do with the AC waveform - as the KLEIN Tool Multimeter is a TrueRMS and the cheap one is probably not -> the "true RMS" has most probably have the more correct value - it would be interesting to check the voltage with an oscilloscope as this would show the waveform causing this AC ... maybe this could give a hind about the source of this AC voltage.
Thanks! You know your the first person to catch that I had the probe in the wrong port. I didn’t even catch that. Guess I’ll have to try and retest again.
Yeah, your not the first person to tell me I need to get a scope. Might just have to bite the bullet and get one for testing.
@@AdamDeLay07 as the cheap and the true RMS show different values, this is an indication, that the waveform is not a sinus. This is the reason why the cheap one measures correctly at the mains which is a sinus waveform
Hi, i wonder if incandescent lamp could light up if you test it on the aluminium frame and ground
Would be a neat test. Have to find an incandescent bulb though. Got rid of all those years ago.
Thanks for the video, grounding is one of the hardest things to learn in solar!
Can I ask what size gauge wire you’re using for grounding? I would imagine it’s eight gauge? 🖖
Yea I picked up a spool of 8 gauge.
Grounding is essentially for safety of person. Nothing else. The theory behind grounding is that if a metal part becomes "hot" and you accidentally touched it, then it is expected that most of the current will not flow thru your body to ground but would flow via the ground wire/earthing conductor to earth. Taking the path of least resistance.
In my case there was no buzz, but i was feelinig it. Definitely not pleasant. Makes me wonder though why in my case it was stronger, but I do have a 240v mpp solar, so the voltage is probably higher.
That’s provably it. I know a friend of mine had one array that had a mix of panels between the two inverters. They were all bonded together using the mounting hardware but not grounded. He got a really good jolt when he touched his. Said he never felt anything like it. Had to be due to the fact that a part of the array was going to one inverter and the other part was going to the other inverter. Double whammy.
A set of drill bit stop collars is about $8 on Amazon.
I learned something new today thanks! Having followed your journey, would you recommend a similar 2x EG4 6500ex for a home system or is there a better available option today for maybe a little more money? The two 6500exs would meet my split phase power needs.
I do know that Signature Solar is supposed to be coming out with a new inverter which on paper looks to be very close to a Sol-Ark, but at a cheaper price point. I'm curious to see how that one performs, but I've only seen info on paper, no real-world tests so far.
I will add that I've had issues getting answers from Signature Solar support. So you might want to weigh that in with your cost based on who you decide to go with.
Thanks! I saw that new 18Kpv was coming out.. I sure hope someone will do as nice an honest review of that one as you’ve done with the 6500ex. 👍
@@terrahillfarm Appreciate that. Would love to get my hands on that unit and run it through it's paces.
Use the Klein and check the Hz of the ungrounded panel. Obviously you have AC current, but at what hertz? A reduced hertz might explain why the craftsman fails to pickup the full voltage.
Hadn’t thought about that. I’ll take a look today. Thanks!
Ok, maybe not today. Next day when it stops raining… 😁
when inverter is closed it still feeds the coils .. ****capacitors with charge or i m wrong
\?????? btw is your solid copper cable a welder cable too ? cause i saw em as welder cables in marketplace!!! maybe soldering ones have more particles to help proccess and i m not aware of that information
I don’t understand what you’re asking regarding ”the inverter being closed.”
The copper wire is just a solid copper wire. Welding cable is fine stranded wire.
If its backfeeding from inverter, what about to put diode there?
Possibly, but you really shouldn’t have to.
Hmm. Mike Holt has a channel about grounding. Very important. Anything earth grounded should be bonded.... All ground rods should be bonded, is what I'm trying to say. Could get deadly if you become part of that bind naturally.
Yeah, it's been a great resource!
The trouble is grounding may not work. Ground is not always zero potential. I have installed many systems including wooden frames and have never seen this potential . Of course you earth,grounding the metal frame may help with indirect strikes. As others have said this potentail you are getting is induced AC comming from a switched mode charge controller.
People are worried about grounding their panels because they think it will make a lightning rod and attract lightning. That's not how that works. The grounding will get rid of the lightning so it doesn't build up in the frame and start a fire. If you have a good grounding system, you will get rid of the lightning fast, and there will be no fire or damage to your equiptment.
@@azwelke2638 the grounding system and a lightning protection systems are actually two separate systems. From my understanding a grounding/earthing system isn’t designed to handle lightning strikes.
When you tie all of your grounds together in the panel, and then you tie them to a ground rod. That ground rod gets rid of lightning. And the bigger the ground rod, and the bigger, the conductor going to the ground rod, the more lightning it will get rid of and the faster it will get rid of it.
They do make surge suppressors, but that's only because people have bad grounding systems for their house. The new electrical code requires two ground rods, at least 6 feet apart and then you would ground all of the frames of everything metal that you bring power to. It might not be mandatory to ground the frame because a lot of people do use these on RVs. But if they are on your house, where are you actually have a ground rod, I would ground the frame. It cannot hurt it. Tying the frame to the grounding system will only help get rid of lightning.
And it would help your breakers trip. If you were to accidentally run a live wire up against the frame like an extension cord. If the frame wasn't grounded, the extension cord could energize it. If it's grounded, it will trip the breaker.
@@azwelke2638 the ground rod may help but it’s not a part of a lightning protection system. That’s a completely separate system. SPDs are designed to handle any possible surges that may come across the lines into the home.
diysolarforum.com/threads/lightning-protection-grounding.86068/
diysolarforum.com/threads/extra-auxilary-grounding-rods-dont-do-it.81027/page-2#post-1042745
What about checking if there’s a ground and neutral bond in the inverter or your main panel. It might be ghost voltage and may be the reason for cheaper meters not getting a correct reading. Testing a light bulb between the panel and ground if it comes on it’s real electricity. If it does come on then it’s ghost voltage. My guess by the way. And thanks for the great vids.
Thanks for the comment!
So the main panel did have a ground neutral bond but the inverter didn't.
It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
Is it possible that the source of the voltage is the inverter circuit itself, because it’s AC, and not the mppt circuit?
Has to be some part of it. Like you said, it’s AC. Now one thing I didn’t test was if I turn off AC IN on the inverter, does it go away.
If you look at your buss bars inside your panels you will see they do not connect in any way with the metal frames not sure where your static voltage is coming from. My panels are also mounted on wood frames and
Thanks, yes I'm aware that there's no direct connection.
It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
People with RV ‘s don’t understand the need for grounding the frame , many deaths have occurred because no frame ground
This is very troubling to me. I had previously heard of such a problem, but it had been traced back to faulty Victron charge controller which was back-feeding the panels from the batteries. I read the comments and some of the explanations are very confusing to me because I'm not an electrician. My basic question is, is such a charge on the solar panel frames normal?
I'm no electrician either, so I have to go by what I hear. Apparently its more of an issue with cheaper High Frequency inverters (like the 6500) that don't have built in isolation between the PV and AC.
This guys a whole lot smarter than me. diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/post-707937
@@AdamDeLay07 thanks for the link 👍
I'm using my 6500 for home backup, but plan to add some PV. I did some measurements from the black and red PV1 input cables to gnd, and to each other using my Fluke meter. I don't think this is high frequency AC. I measured 230V from red to gnd, 190V from black to gnd and 40V between red and black. This is with the Fluke set to EITHER AC or DC. It appears that the path is very low impedance, so I can't just ground the black PV input lead, and I can't connect the ground lead from my Tektronix scope to either lead to look at the signal. I ordered a handheld battery operated scope so that I can investigate further.
Are you testing this with the panel connected to your inverter?
Here's what I've found by someone a whole lot smarter than me on the topic: diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
I scoped the PV input leads to ground and found that I have a 430Vp-p square wave at 60 Hz on the black lead, and 470Vp-p square wave on the red lead. These are clean, well defined square waves. Is this normal?
@@larrylp2192 Hard to say. Since you have scope data, I might recommend getting on that thread I shared and post your data there.
@@AdamDeLay07 Thanks for the link. I will definitely weigh in on this. I also contacted Signature Solar about this and will contact EG4. There should be a warning in the manual. I think a lot of people probably assume that the PV input, being an input and not an output, would be safe to touch. I got shocked while wiring my PV disconnect breaker. It could easily be lethal. You can draw a LOT of current between either PV input lead and ground.
@@larrylp2192 let me know what you find out!
I was thinking about this today and now I'm wondering if your Victron gear does this too or if it's just a 6500EX oddity. Maybe a video idea for warmer times. :) I'm guessing not.
Actually, I covered the “shocking potential” in this video:
ruclips.net/video/5Q22W5bhs-c/видео.html
@@AdamDeLay07 Oh no I missed an episode, my bad. I figured it wouldn't be an issue given it's Victron.
@@SolarShenanigans no worries. With the 6500s, there’s little to no isolation between the PV and the AC H Bridge. That’s why there’s AC power bleeding on the frames.
i was getting 70VAC @ 144 MHZ on my 8 x 340 watts array until i grounded it, your getting maybe 20 milliamps but it still give you a zap, doubt its dangerous but uncomfortable to the touch !
Voltage tests need to be done with a load connected. Most meters don't have enough internal impedance to create a load. A Knopp type voltage tester provides a load so it would provide a more accurate voltage measurement. Even in your vehicle... if you place your meter across the battery you'll read approximately 12.7 vdc. Now turn on your headlights and you will get a more accurate measurement of the state of the battery. Yes the voltage will drop some. Now crank the starter and you really check the capacity of the battery!
Did you have the AC Inverter grounded before this ??? Did you test after grounding it???
Yes. The inverter was grounded because I had AC IN coming from a panel connected to the grid.
It is a little unsettling, but would it start a fire or kill someone? Is your neutral bond disengaged in the inverter? Most of mine are in wooden frames and ungrounded. I am running two different systems though - 1600 watts feeding a Bluetti AC 200 max going to a transfer switch, and a 12 volt 2000 watt system with a LiFePO4 12 volt being fed by 400 watts to a 30 amp PWM controller. I have wondered about this before, I guess I will check it now. I know you said the voltage was not being compounded by the wood screws and fender washers, but that should bond those panels together allowing for just one grounding point. It could be done with spring loaded clamps and cable incase you have to move the panels occasionally.
Really hard to say. I mentioned that @Gavin Stone was hit pretty hard when he was working on his LV6548 arrays. It seems to all be related to the cheaper HF inverters that don't have isolation between their PV and AC.
There didn't seem to be an actual pattern of X panels = X volts. I had thought there was initially, but was still getting 70 with the 1 panel as opposed to 140 with 6. Doesn't make much sense to me.
@@AdamDeLay07 Thanks for the video and the reply. I will investigate my stuff and keep it in mind if I upgrade to a hybrid system. I'm building my 12 volt system 1 battery at a time with the intent of jumping up to a 48 volt system, but there always seem to be issues with EG4 stuff. Is the neutral-ground bond disconnected in your inverters?
@@PWoods-cd6tk Not a problem. That's how I started. In fact, I'm looking to repurpose my old 12v system shortly into a portable power station. Good luck!
Yes, the bond screws are removed in both my inverters. The only N/G bond in my environment is in my MSP.
Depending on the inverter used is the grounding of it,, EG4 will send charge back to panels,, dnt like it so it may be the issue ,, try measuring the voltage on the receptacle of the mppt side without panels...
If I recall, I did check that when I was upgrading my PV connections and I thought I was getting 35v directly from the terminals without any PV connection.
@@AdamDeLay07 No expert here, by any means, but it kind of sounds as if this issue is originating in the inverter (s).
Hey Adam, do you have any issues with those panels blowing around on windy days or are they anchored?
I haven’t had any issues with wind and they’re not anchored down.
How on earth can that happen? The frame should be completely isolated from the cells and internal buss connectors. The glass and silicone layers should insulate all electronics. Is there something that Renogy is not telling us about their panels or did this happen with all of your panel brands? Something I am missing?
It turns out that the cheaper all in one inverters (like the eg4 6500 and the MPP lv6548) have some issue with their H-bus and isolation. It allows AC to somehow bleed on to the PV frames. I don’t understand much of it myself but I’ve had much smarter people than me try to explain it. It’s over my head.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
It’s not specific to the Renogy panels, because it happens on my SolarEdge panels as well. It all goes back to the AIO inverters. Ultimately it reinforces the need to make sure you earth ground your panel frames.
@@AdamDeLay07 Wow! Crazy. I have not checked my new array but the old one is on that big metal frame from Powers Solar Frames. I may check just out of curiosity.
@@CountryLivingExperience yeah just pick one panel that’s connected to your 6500s and disconnect the ground. Then measure the AC voltage between the panel frame and the ground wire.
It’s been a while, so I can’t remember if I found out that you had to have AC In connected to the inverter for the voltage to show up.
I know I’ve heard of others with this issue on both EG4 6500s as well as the LV6548s. I’ll be interested to hear what you find out.
Assume we have straight dc panels no micro inverters etc . What voltage is on the panels frames ? Coming from where ? Induced? Since there is no conventional trip protection for dc to detect leak What does earthing do for you ?
You can see the voltage in the video. It’s coming from the inverters.
It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
I don't understand how you have an electrical connection to the frames. Did you run an ohm test from - to frame or + to frame?
Personally, I don't get it either but it turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
@@AdamDeLay07 yes but all of my solar panels do not have an electrical connection to either the positive or negative leads. The panel is suspended by glass.
@@RICHIE26636 correct, all panels should have an air gap between the panel and the frame. Like I said, I still can’t explain exactly how it’s happening at the panel, but it is coming from the inverters. Not being an electrical/electronic expert, I really can’t explain other than what’s been told to me by people much smarter than me.
air friction creates static. you can take a bare copper wire and set it vertically in the air and it will produce voltage. the higher the wire the more the voltage. main reason they run lines in the air, that static helps boost the grid
Hahah. That's funny, but not true. Transmission lines are in the air because air is a great insulator. If one were to try to bury the lines instead, the cost of doing so becomes enormous because massive amounts of extra insulation would be required. Transmission lines are HIGH up in the air because they are energized from tens to hundreds to even a million volts, and that energy can easily couple into anything nearby. Since ground is basically ground, such coupling can be catastrophic. So the lines are high up in the air... and even so you can still feel the electricity in the air when you walk under a high tension line.
There is a voltage differential in the air that goes up with height, and the voltage itself can be quite significant. But the amount of current you can draw from it is miniscule because you more or less instantly deplete the electrons in the air next to the wire (wind or not). i.e. the voltage differential will disappear when you try to suck energy out of the wire.
Static electricity from air friction is an equal opportunity employer. It isn't generally all that much energy in the first place, and it applies equally to all the wires in the transmission line so it does not create any sort of voltage differential that could be harnessed.
@@junkerzn7312 you are just repeating what you were told by another that has no clue. all you have to do if go read about other things and put it together but you wont , it requires reading lot of it and ohh yeah, the ability to comprehend
@@tonymengela3575OKAY, **KAREN!!**
Interesting that the anodize didn't insulate them to ground
Use a step drill to stop from going through or put a piece of metal in between. The sanding sponge is filling your tip
I was going to suggest a drill stop. I had to drill out the holes on all the panels of the last array I installed and that's how I did it. But the step drill would work too.
Even if there is back feeding why is there voltage on the 'frame'. Shouldn't it be inside the wires or inside of the solar panel. Am confused
It turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
I have that same multimeter. I don't think it was cheap and it works for me! Probably got some loose connection or bad 9v battery?
I think it’s just not as sensitive as my other ones.
@@AdamDeLay07 It is an old meter. Try some dielectric grease on the probe inputs to the meter for better contact.
My arrays are not grounded and will give you a good buzz on the frames even when not connected to charge controller when the ground is wet.
I Earth Grounded each of my SIX (6) PV Panel Arrays
to an 8' long Copper Coated STEEL Ground Rod
SIX ARRAYS = 36 Panels
SIX Ground Clamps on ONE Ground Rod
in a 6S / 6P Configuration
to a ECO-WORTHY Six (6) String Combiner--Box equipped
with a SURGE-Protector circuit = one >MORE 6-AWG Bare Copper ground wire
= SEVEN (7) Direct-Bury Ground Clamps on that ground rod ...
in total
...
COOP
Buzzing is from static charge possibly thousands of volts, very little amperage, that’s why it’s not zapping you. Caused Most likely from the wind passing over your panels. This is not from a/c. You seem to have some a/c voltage,most likely from your inverter but likely is fantom voltage with no real amperage. A small wire from your panels to ground will dissipate this type of voltage. Earth grounding will not dissipate and zero out a/c voltage. If you have true a/c voltage with small or large amperage it will continue to flow on the wire even if earth grounded. Electricity does not only follow the path of least resistance, it follows ALL paths. This is why we use grounding not earthing. Very confusing but it is very important to know the difference.
Another reason why you would want to ground the frame is so that it cannot become energized from another source.
If you are measuring AC voltage on the solar panels, this is a feedback from inverter. You better test your inverter, most of them high freq are floating.
Thanks for the comment. It actually turns out that this is a fairly common problem with the cheaper HF inverters. I've gotten quite a few responses from people using the same style inverter (whether SunGoldPower, MPP or EG4). In looking through the DIY Solar Forum, it seems like these cheaper inverters don't have proper isolation between the PV and AC H-Bridge.
diysolarforum.com/threads/eg4-6500-voltage-on-pv-terminals.55201/#post-707937
25 volts would not have been enough to create that buzzing. Your meter isn't reading it accurately.
Edit: as you saw by using the other meters. I also question their accuracy... you really need peak voltage, and the best those meters might give you is true-RMS - an average. In any case tho, the current is minimal, nothing to worry about other than a possible surprise.