Hi Andy, You might want to clean off the conductive grease you used. I believe that many manufacturers indicate not to use grease for primary power connections (between the conductors, in other words between the battery terminal and the bus bar). Also, it might be that the nuts are slowly turning as you have a lot of temperature changes day to night so that thermal cycling might let the nut spin a little bit. maybe better spring washers, or even a nylock nut to prevent that from happening.
I'm sure it's mentioned in one of the almost 250 comments but if you were planning on running loads like that often a small capacitor banks would smooth that draw curve out. As I've mentioned in other videos beside my 400ah banks for garage and home, in my car audio build I use 2-630 farad ultracaps to handle surges and a bunch of lithium feeding the cap banks. It makes for extremely even draw and a whole sh"%ton of peak draw that even the lithium doesn't come close to providing. This is one of my many favorite videos of yours I love seeing things put to the test
Thank you sir for sharing your developing story - I am in the process of setting up a off grid garage. I have learned a lot from watching your channel and I thank you for all of your efforts :)
Great job on the little details terminal to bus bar in millivolts . Thank you for this knowledge of the information you bring to the RUclips audience. Your cabinet I think you need to install a fan temperature control to get the best power consumption out of your unit due to the heat.
16:30 VA(power factor, usually 0.8) and W are not the same. You have to multiply VA to 0.8 to get the real Wattage. 3000VA*0.8=2400 W witch in your specification is verry acurate.
The S rating on the shredder is service factor. S 1 is the maximum continuous load. The S6 is the maximum it can do but only for 60% if the time. Most machine tools are rated like that as it allow manufacture using a smaller motor. Am envious of your high end equipment. I do similar experiments but with lead acid battery and Chinese electronics!
Sharyn Comstock, I would suggest cabinet exhaust fans be used controlled by a din-rail thermostat. Positive air flow will be much better than passive ventilation.
I see two things that I question. 1. Put a big hole in top of the case and duct an exhaust fan to get more air flow past the inverter. Thats your only option besides getting a bigger inverter that is in range for the temperature. 2. In your diagnostic at 21.22 some of your bus bars appear to have large holes, and it appears the grub screws and washers are of different materials, which pulling high amperages could cause a problem. If that is the case you need to maximize the surface area of the cell terminal in relationship to the bus bar. The bus bar, even though heavy still acts as a fuse and if you could pull enough amps would fail. *** Always love your videos Thanks ***
Hi Bob, as I explained in my newest video, I don't need a bigger inverter and theses are corner cases I'm testing here. All bus bar equipment is stainless apart from the terminals and bus bars themselves.
Why is so unknown to everyone inverter spec is for 20C degree. Over 30 you get roughly 75% top close to 40 under 50% only without overtemp. Surface temp is absolutely not even close to internal when you get that inside it is around 80C degree internal , it switch of close to a hundred. I tried to tell somewhere back in time but unlikely read that. That incredibly hot climate simply just take a double on a desired number. This why i also wrote the cabinet is completely unnecessary for that climate. Nice to see the experiment, i like it very educational. Nice garden!
Your videos are very detailed and informative . Thank you so much for that . Regarding the inverter ratings , VA is the apparent power not taking the power factor of the load into consideration . Kw is the real power taking the Pf into consideration . Most AC generating devices are rated at a PF of 0.8 so your 3Kva inverter can only give 2.4Kw Cheers Ross
Hi Chuck, I think you mixed this up. It's the other way around. VA takes the PF into account and can therefore be higher than the actual W. Your own example is correct though 3000VA apparent and 2400W real power.
I think by polishing the terminals, you made them so smooth, that the grease is now evenly spread between the layers. If they are not smooth, the small elevations and grooves will be pushed "into" each other leaving the grease in the "gaps".
It seems like some movement is occurring with your terminals with high amp loads, the terminal Grease maybe increasing the movement. Batteries could be expanding a little bit, try cable busbars and see if it helps.
Make crimp conections with two lugs and cable change the rigid bus bars and measure the voltage .....make video and compeare.... I have same issues with my cells as well.... Excellent job....spot on ...👍
Honest....i think rigid bus bars are fold that u dont have proper fit to cell terminals....u have to consider that not every cell terminal is made so acurate by and if u have
I have bus bars made thin cooper 0.5mm and one bus bar have 7those cooper strips bonded together with heat shrink tube so i have dismantle bus bars and use only two cooper strips in one conection... On 100A load no heat at all....
Andy, minor cell voltage deltas are quite normal. I find that it is common to see cell voltage deltas of up to 30-40 mV when running at higher current levels. I don't think you have a major issue here with cell voltage discrepancies at the load levels you are running at. Just be careful not to tighten the connections too much. The more you tweak the terminal connections, the higher the probability that you will strip the terminal threads. Then you will have a problem.
You can get a wireless Bluetooth range extender to connect to the Victron kit. If you put it near the window you will be able to connect when you are in the garden. It is mains powered, but you have solar to take care of that.
Of all my Bluetooth devices, my Victron Controller's signal is the weakest. Ian H, what Bluetooth range extender is available that would connect to Victron Controller? My searches just find extenders where a 3.5 plug is involved, like a speaker output.
Andy, stainless steel is a poor conductor. Until you use a brass stud, washer and nut with a spring washer you are always going to get mixed results. The elongated hole in your busbars is also giving different a contact area resistance dependant on position. You need new all copper busbars and the BMS connection needs to be moved off the terminal and directly connected in the middle of the busbar.
@@OffGridGarageAustralia I have that setup, and works good. Indeed, stainless steel has a high Internal resistance, so bad for electricity. Good news is that you don't need / want that to do the work, the bus-bar to terminal contact does that. Don't worry about contraction and expansion, it's a tiny piece of tinned copper, fairly flexible with 4Nm Torque. A few mm difference between 2 terminals is easy corrected by its flexibility. Terminals themselves are in special housing that is build to buffer for the micrometers expansion/contraction.
Hi Andy. One of the best things of your videos is that make hundreds of people arround the world to think about your problems and projects :-) My thoughs about two thighs: 1- the thermometer gun you use, (IMHO) I think is not used correctly. The laser dot is just a POINTER showing the TOP of the AREA the sensor is reading. Such surface AREA size DEPENDS of the DISTANCE beetwen the sensor and the surface. Think it is like a light torch that iluminates the surface according with the distance. At one meter, the reading is imprecise since is the "average" of a BIG surface (and not in the red pointer at all). 2- the voltage drop in the studs has to be studied carefully. Using grease just make the problem worse. The main contact area is BELOW the Bus-bar (the "terminal" itself); is the flat metal surface where the stud is inserted. The nut and washer material is almost irrelevant (but the diameter of the washer not). The most important factor is the flatness of the "terminal" and parallel to the bus-bar´s lower surface (more than cleanliness, plating purity, and so on). Dilatation is an issue, so, in my opinion, "omega" shape is much better than just flat, and even much better a flexible jumper. Aluminium is very reactive metal and is oxidized almos inmediatelly in contact with the air (ask to any welder about why it is needed to use argon arroud for welding aluminium), and aaluminium oxide is not a good conductor. Touching again and again the nuts is not a good idea, since it stresses the stud and its anchoring inside the terminal, damaging also the metal surfaces (coper and aluminium are very soft) and making necesary to repeat the tightening for ever. I sugest the use of conical washers (spring washers) that makes a constant pressure adapting automatically to the temperature induced dilatation.
Thank you for your thoughtful comment. Very good point. I will use a FLIR camera soon for these sort of tests. Hope it gives us better results. The gun is just an approx, easy to grab and shoot.
Overall it's conciddered bad practice to put anything between the busbar and terminal except antioxidation compound. The last is in many variations from di-electric grease to special silver based paste. The bus-bar is coated, so it isn't copper to aluminium.
I bet your terminals expand when pulling high currents. Get some expanding washers and torque connections down when warm. Or maybe the plated copper and aluminum don't mix for connections. Try aluminum busbars. Or maybe just a few busbars have bad plating.
Interesting what's going on with battery connection / bars. Don't think stainless is a good conductor from memory, go for copper and look to see what they offer to go through oxide layers. I remember Oz! Gets hot during the day, so if charging at night look to vent, maybe from outside air through a bug screen. Need fans and remove that hot air. Keep on charging. Mark
Only the stud is made out of stainless. This does not conduct much power. 99.99% will go from the terminal area to the busbar directly. The stud and nuts only push them together.
Andy, what about lapping the terminals, by applying light pressure with the nut and lapping compound between buss bar and terminal, while turning back and forth? This should make sure that the buss bar and terminal have maximum contact area.
Hi Andy i'm from Portugal and i love to see your vídeos. But i have a question: why didn't you bought a 5k inverter?! For your needs i think its a better choise.
There is anti-oxidant paste designed specifically for electrical connections to aluminum which prevents aluminum from oxidizing. That's likely why you have to periodically loosen and tighten nuts to scrape oxidation off.
With regards to the inverter I think that the learning point is to over spec by at least one level. I use a 10kw inverter for a 7.2kw car charger. If I run a kettle at the same time it copes (9.5kw) but brings on a warning light. Not a problem for intermittent use but I keep it to 7.2kw for continuous use. Probably good to choose an inverter so that it doesn't run continuously more than 75% especially in hot climates. As the Victron equipment has covers over the terminals I didn't put the inverter inside a cabinet which allows better cooling.
Andy, I have following theory: you should not care about the potential at the bolt, what is important is the potential difference between the aluminium pole of the cell and the busbar and also the ring terminal of the BMS. I think, and again that's just a theory, that the problem is created by the stainless steel washer which is placed between the busbar and the ring terminal. Remember that stainless steel has a lower electrical conductivity than copper.
Well, that's exactly what I measured. The stud IS the terminal. It's threaded into the terminal so should have best contact. As other terminals show, they have 0mV so there is very good connection. The BMS connection is not so important because there is no current going through. It's just a voltage sense.
@@OffGridGarageAustralia I think the voltage drops you measured has convinced me to redesign the way I'm going to connect my terminals to (hopefully) avoid such problems... to either solder (or clamp) all wires to one ring and tighten that ring to the terminal (like the positive battery terminal is designed in a regular automobile), or if I do use busbars, I'll drill a small hole in each busbar for mounting the BMS sensors.
@@OffGridGarageAustralia Now that my 16 (176 Ah) cells have finally arrived (I'm now in the process of top balancing them) I just have to properly use what I learned from here (and other great channels here in the YT-DYI-PV community). I want to give it a try by using copper washers istead of stainless steel ones. Let's see if that brings any improvement. I have already observed this thiny drop in voltage during my capacity tests. By tightening, the shown Voltage, at the capacity tester, increased by about 10mV. At this time I intend to use the busbars which were delivered together with the cells. I will use, for the beginning, only a maximum of 1 kW for charging and discharging, so they should be enough (my system is AC coupled so I have all the parameters under my control, I hope at least).
In our Data Center we use 220V fans in the cabinets, They make a bit more noise than you are used to from a computer fan, but blow like a tornado, but watch out for your fingers, I also use them myself in my cabinet .. I wonder if those bus bars you use are made of copper or secretly not made of steel, if your cells are not exactly the same height, it will never connect well, copper forms more easily, so mayby.....
Nice test ..... Now 5kva inverter would work without any problems ...your high enviroment temperature it makes more difficult to work .... I would calculate normal load +30-40% because of high temperature but already know that... And because is free power eventualy u will add more load to the inverter and max out the output or work on max whole time... Like the videos ..... U hit the common problems spot on...and not many do that ....many questions are that way answered...excellent....👍
Reference your busbar/battery terminal problems. I wonder if the top of the problem cell terminals are no longer absolutely flat. Perhaps polishing them caused the top to become curved? If so this would reduce the contact area. I am not totally convinced that the conductive grease is a good idea. If it has slightly reduced conductivity it may actually be impeding rather than helping. Blocking direct metal contact maybe worse overall than helping to make up for the microscopic gaps. If the surfaces are totally flat and reasonably smooth the contact resistance should be minimal. If you are worried about corrosion you could add grease afterwards to act as a moisture barrier. I use thicker aluminium busbars with no grease on a pair of 12v LiFePo4 batteries in my RV. No risk of dissimilar metal corrosion and so far no problems.
Kind of sinister when you think about it... In the winter, inverter will provide a lot of power, but solar won't. In summer, you will produce a lot of solar power, but the inverter won't let you use it all.
@@KD2HJP Actually, I wish these cells were available when I did my solar system about 18 months ago. Instead of 4 Battle Borns for 5120Wh, for $4k, I could have had, in the same space, with a little more weight, 14kWh of energy for half the cost. Oh well, I still love my solar (540W), inverter (2500W), lithium system in my RV. It has freed us from the tyranny of the generator!
@@daveduncan2748 I just picked up 48v Gyll 100 AH pack. I have been experimenting with several LiFePo4 cells, for years. Whilst watching Andy over the past several months, and hitting all the same obsticls, I have thrown in the cheap towel, and spent a few bucks more for my sanity. Can't be happier
I would like to advise you to check the data sheet for this inverter on victron web page. Continuous real power at 25 Celsius is 2400W. As the current draw for inverter at the terminals raise, the internal temp will also raise ... so youre gonna be working at >2400W. Always size your systems with buffer and consider the real power with ambient temp .. just giving some technical advice.
my bad .. you covered that in the video however .. a 3000VA inverter doesnt mean run at or above 3kva, thats apparent power so you should work with the 2400W real power
I couldn't help but notice something about your voltage drop: When you measured between a terminal and a bus bar you had it, but when you measured between a terminal and BOTH ring lugs, you didn't. Completely crazy theory here: Could it be, that between the terminal and the bus bars there is a difference in plane, that they are not absolutely parallel to each other? Would explain the behavior you have. If it weren't so much work, I would suggest to change the bus bars for cables with ring lugs, so you can avoid any angle related problems. Maybe you could take that to mind and consider it as a last resort, if nothing else helps. Maybe you could exchange the most bothersome bus bars already and look, if it makes any difference. If yes, you could do the other ones later on. You need to remember: The bus bars are ONE flat piece of metal. In this case, with this short length between contact points, it doesn't like to bend and twist very much, copper or not. With a piece of cable with ring lugs you do not have that problem, as the cable is made of flexible strand material. (I would have written that in German, but didn't want to exclude the international viewers.)
Andy, There are some things that need to be cleared up. Your inverter is only rated at 2400 Watts. The VA rating is not watts it allows for .8 power factor which accounts for the magnetising current of your motors. I realise other viewers have tried to get this across, it is an important fact to know and understand. Total VA rating is Watts (true power) plus Volt Amps Reactive (VARS). VARS are necessary for any AC magnetic device to operate. The grid is designed to operate at .8 power factor. Now having said that, you will do well to get rid of the box, once you arrange proper air circulation the inverter should run happily enough at 2400 Watts and up to 3000VA. My set up is a pair of Giant brand 4000 Watt / 5Kva all in one units connected and programmed in parallel / load sharing. In theory they should start a load up to 20Kva (approximately a 5 KW motor DOL) on their own, without mains support which they can be programmed for. They will run welders. The installation / user manual gives strict mounting instructions especially around airflow. They recommend wall mounting with 500mm above, 200mm each side and 500mm below for 55 Deg C ambient. This afternoon 64 x 310AH CATL cells, when they arrive I will see how they go. This to upgrade my system from AGM which worked well but has limited cycle availability. I have already taken a variety of Bellville washers into stock for the upgrade project. In case you don't already know Belleville washers are conical springs that spread the force to their rim which can give up to 10 times the effective contact area. I am also considering hardened washers for their electrical contact spreading properties. I also have in stock Utilux H2397 Electrical Jointing Compound (Aluminox) which is certified for jointing of Aluminium electrical connections. The reason my choices are so damned conservative is 48 years as an industrial electrician working with Megawatt class inverters and heavy DC. I will be interested in how your contactor based BMS goes over time. In industry DC contactors are the single most expensive electrical maintenance item, so expensive if fact that on mobile equipment only tyres are more expensive. They are now superseded in new equipment by IGBTs and each day more legacy fleet get retrofitted with IGBTs. Regarding the issue with your Charge controller losing its marbles, I would start at that relay. Your balance lead connections are not at the standard I would accept. Trade quality "Copper Grip" lugs with larger palms are available. When I do mine I will drill and tap the busbar for the BMS connections which will be easier. Do not use cheap "Vinyl grip" lugs. The copper grip design has a double copper sleeve which forms the correct crimp. The cheap crap is for decorative purposes only.
Your videos provide little nuggets of info that i don't see anywhere else. ie: toghtening a terminal while viewing the BMS readout. Have never seen that. But, it is relevent!!! Also. How about the crimp of the terminals for the balance leads? Perhaps some are not tight?
Try copper washes, and make your own bars with ½" copper tube. For the over temperature give them more space in between they are too close to each other.
That's a very hot temperature for an inverter, I doubt my radian would handle full load in that kind of heat either. It may but it would be running at max temp for sure.
The inverter is just to small,and yes,the box where it is inside is to small,put it outside or drill 80mm holes and extra fans,I like your experiments very much 👍those batteries have to small fixings there are batteries with M8 bus bar connections
The inverter is not to small for my application. I only have the irrigation pump with les than 900W. This was to test overload and overheat function of the inverter so I know what I can expect in this climate.
interesting to note.... hadn't considered the the limitations of a hot summer day. is the box you have it in limiting air flow partially? some temperature control computer style fans on the top and bottom of the box would be good I'm sure.
I would use a zinc-coated Internal or combination lockwasher. That way any movement from heat expansion is negated from the bite, or bites if combination washer is used, upon application..
This problem does not come from heat expansion. The batteries and terminal stay cold all the time. Even during hot temperatures during the day the cells itself are up to 10° colder than the ambient temp.
My EASUN 48V/5KVA inverters capable of twice that power for 5 seconds never have the slightest problem in starting and running a load like my air compressor AC induction motor which takes more than 25A startup current @230VAC, provided my lead-acid batteries are charged! The first of those inverters cost me only 500 bucks until I wanted another six of the parallel version @ $1100 each, delivered promptly by the Shenzen manufacturer for my purpose of a 3-phase 30KVA system.
The chipper shouldn't be started with sticks in it. They always trip breakers with sticks in them. Long low current extension cords take away starting power. Try with a higher rated extension cord. An outlet on the outside of the garage would come in handy.
I added also a 11cm diameter hose with an active ventilator in it under my EAsun all in one inverter right under its 2 ventilators to catch its blown out hot air to lead it outside the technical room it resides in. Would become a sauna otherwise. Also added 2 pc fans next to the intake holes of the inverter to make a stronger wind flow going through the inverter (controlled by 38 degrees temperature switch, so only active when needed)... helped a lot. pc fans are hooked up to the 51.2v battery via a step down buck converter to 12v (all cheap on AliExpress)
Do you have a washer between the balance leads and the bus bar / inverter cable? The screw, nuts, washers, etc. should not be used as part of the electrical circuit. Threads and stainless steel, not good. They should be considered as part of the mechanical force holding the highest current component against the battery terminal with lower current components stacked on it and compressed by washer and nut.
I have the same issue on my Lishen 272 battery pack with the resistance on the packs changing, I think it might be related to expansion of the cells when charging / discharging. I am thinking of trying to temporarily clamp the cells with kapton tape to see if that stops the movement.
I have space in between my cells so they can expand (which I have never seen actually). I think it's purely oxidation related. I've ordered some other ant-oxidation paste and will try this out on these terminals.
I had a new lifepo4 battery that the surrounding plastic around the terminal was higher then the metal terminal post itself by about 0.5mm, I had to use a sharp knife to trim the plastic away from terminal post.
@@OffGridGarageAustralia basen.en.alibaba.com/ I have brought many batteries from them over time, what brought it to light was a very hot busbar, checked that the bolt was tight, which it was, but on removing the busbar found the metal post was below the plastic surrounding it
just a tip: if you are measuring temperature with the infrared thermometer always go as close as you can to get the most accurate results, for example if you are 30cm away then it measures the average temperature of a 30cm circle approximately, so if you get close you get more accurate results
I think it's pretty simple, the busbars are too rigid and the expansion off the cells makes the connection move around and make inconsistent readings. You should use copper flexible stacked thin sheet busbars. Also don't tighten the nuts without holding the screws that go into the battery, you could be pushing a bolt into the cell like this.
The cells have space in between them. Even if the would expand, the bus bars won't move. I never tighten the nuts without holding the set screw in the middle.
@@OffGridGarageAustralia according to the specifications, the cells should be compressed together. This prevents delamination. Look at it like a phone book on its side.. that doesn't stay good long time :-) Contraction/expansion is micrometers, the terminals are in "soft plastic" to compensate for this. As I use tubular wrench, I can't hold the studs. Instead I used locking agent to fixate them.
I could not see any ventilation in the box with your Victron equipment. I presume the door is normally closed. Is there any ventilation with the door closed?
IIRC, the battery terminals themselves are aluminum, so he needs to use anti-oxidant paste for electrical connections to aluminum conductors. Otherwise, the aluminum will keep oxidizing and need periodic loosening-tightening to scrape the oxidation off.
Hello Andy, i have a question. I've planned to buy a Solar 6000 EP. but i realize the inverter is not so far in the setting, we have only the possibility to set :1.Battery Type 5.Max Charge (A) 2.Battery Capacity 6.Max Discharge (A) 3.Nominol Bat Voltage 7.*Discharg Depth 4.Battery Cell Type DOD. Do you think it will work with the custom 16 cells batteries with the JK BMS ? we cannot set the absorption or float with this, and Victor is not really the same budget to set a 6 KWh inverter ! Thanks a lot for your help and nice videos !
I know you're set on a closed box with no noise or ventilation but that inverter relies on good airflow at all times. To keep it in that enclosure you're going to have to cut two 120mm openings for two 120mm fans, one intake at the bottom and 1 at the top to have any hope of keeping the inverter operational. If the inverter were mounted outside of an enclosure it would probably give you full wattage. Are you absolutely certain the bus bars are pure nickel-plated copper or aluminum? Consider buying some pure copper bar stock from www.onlinemetals.com - I did that and constructed my own .75 inch x .125 inch thick bus bars that run cool as a cucumber (or night frog in your case ;) ) Using copper ring terminals as opposed to the questionable (tinned aluminum?) version you have would probably eliminate the BMS reading problem Keep up the great videos!
Trying to think into the future a bit, if your hunting for fans. The 120mm Delta fans are awesome to cool things down I upgraded to them a few years and wow they make a big difference on the equipment over-temperature problems. So looking into the past and bus bar ideas look for the flatter bars with rounded ends. Nickle plated copper ones the there are multiple lengths available on aliexpress. I would also suggest using a torque wrench so that they are all exactly the same. Now really not sure the small differences you are seeing is much to worry about maybe can set the alerts to something less perfect. Seems like there may be a point to stop and be happy with it.
120mm deltas are monsters :-) tremendous amount of air pressure and high volume. Sadly.. LOUD!! I switched my deltas for "silent wings 3" what is for noise level a lot better. They don't give the amount of flow or pressure, but a few of them will do the same, at same or less power usage and they last +30 years. The small difference he sees is really something to look at. If you have LiFePO4 cells you know. And Indeed... Torque wrench! Adviced is 4Nm on the nuts of 6 mm headless bolts. About 350kg pressure. I just bought a digital Torque meter that goes in-between for this purpose. Really difficult to feel by hand the exact torque!
@@frankfromthailand2190 Yes need to use a fan controller with Deltas they last forever well they are made to last and nice and quite idling along and as is gets hotter they have the power to cool it down.
Andy, as far as the loss between the bus bar in the battery, you may want to use a torque wrench and torque the connection to the factory specifications. That may help?
I haven't got one and don't want to spend $250 one a working torque wrench. The cheaper ones are most likely not working correctly and showing random torques when compared to expensive ones. With the set screws now, The torque can be a lot higher than as with the screws before.
Search for digital Torquemeter The one I bought was about $35,- and does 1.5 to 30Nm. (1/4 inch connection) They aren't as exact as $250- kind, but fairly accurate. It does help making all the nuts the same torque, minimize the variables for errors. Obviously, terminals and bus-bar needs to be clean, fat/grease free and as free from oxidation as possible before installing. Di-electric grease or ox-gard helps with the oxidation prevention
I was just about to ask you if you tried to measure cell voltage with your voltmeter and comparing them to what the bms is saying, I like the Idea of swapping bus bars, are they the same cells you were having issues with before you polished them? If you really want more fun I would top balance again, and disable the bms balancing and see how balanced the cells remain after a couple of midrange cycles, but I know you won’t be keen on that because of the amount of time it will take.
Sold I want one of those electric chippers. Heat is our enemy for sure. lol Use the metal siding for a heat sink and turn on the sprinkler hose on the outside of the garage. Copper bus bars with the bms lead soldered on may take some of that away. We await your solution Cheers.
Did you put you some grease on them terminals otherwise the oxidation will keep doing that especially in your climate those are not LED they're aluminum
"A quick tick with the spanner and it's fixed. But what is the solution?" - it sounds like you have a thermal cycling problem, which means you have a current heating problem. you can change the geometry of the busbar connections so that the pinching direction is shorter (the terminals are flatter - thermal expansion/contraction in the pinching direction is smaller), or you can increase the overall cross section of the busbar (increase cross section, reduce resistance, reduce heating), or you can do both (best option). you can try spring washers, but they'll just reduce how often the issue becomes a problem, and it sounds like the geometry isn't great and the busbar is undersized for the current you regularly carry. i'd make the busbar more beefy. note: adding multiple parallel busbars is the same as increasing the cross section of a single busbar.
@@OffGridGarageAustralia 60A isn't that much, but I'm not sure how thick your busbar is or how hot and cool it gets each day. If the connections keep going bad over time, and you keep having to tighten them back down to correct them, it's almost always because of thermal cycling - when the busbar gets hot, it expands and either it or the bolts deform just a little, or it might cause your securing bolts to back off a bit. When everything cools back down, a gap is left that causes the connection to be intermittent, or the bolts slowly get loose and eventually the connection turns bad. You can try serrated locking bolts/washers, but they tend to just extend the time period in between tightenings. I suppose you could solder all the bolts to the busbar - it'll take a lot of heat, but the thermal cycling likely won't be an issue anymore. Even so, I think it's better to increase the cross section of your busbar to decrease its resistance and thereby decrease the current-heating caused by the resistance and the current flowing through it. Maybe as a test you could bolt on a heatsink to try to keep it from getting hot - if that at least partially cures your connection degradation problems, then you know the issue is thermal cycling, and you know one way to correct it is to increase its cross section. Another test would be to hook up a thermal sensor to the bus bar so that you can measure its temperature throughout the day, lets say for about a week. That way you can quantify the extent of the problem. In any event, the title of your video is extreme heat - if the electronic equipment is getting hot, it stands to reason the busbar is getting hot too.
@@OffGridGarageAustralia as long as you're checking them when they're being used, then i guess it's something else. the locking washers or soldering would be some options. could the crimp joints at the lugs be wonky at all - anything mechanical near the bolts you tighten down? is all the metal copper, brass, or solder?
Serrated flange nuts are large diameter and apply pressure at their circumference. Perhaps your bus bars and/or terminals are slightly dished? Bus bars actually only make true contact with about 5% of the area of terminal - and that’s for a perfect joint. Conductive grease is not actually conductive and cannot help improve the 95% area that’s not making full contact. Conductive grease introduces another metal (e.g. copper or zinc into the aluminium / nickel joint which can promote corrosion - particularly in a marine environment - and is therefore not recommended. Dielectric grease is used for un-plated copper busbar / terminal joints because corrosion can occur in the 95% copper not in intimate contact with the terminal; however aluminium terminals do not need grease as their oxidation prevents corrosion. Try serrated nuts and clean, dry and tight joints for consistent low resistance connections.
Overheating: How much space does the manufacturer specify around the inverter case? How much airflow (m3s or cfm) does the inverter need? Does your cabinet have enough filtered openings to allow that much air in and out of the cabinet? I'd say build an Arduino or similar temperature monitor that drives a display of "Do not exceed XXXX watts." based on the inverter case temperature. Terminal voltage drop: Did you use a torque wrench to tighten the connections? I bought a small (in-lb) torque wrench to ensure that the battery connections were tight enough. If proper torque doesn't resolve the voltages drop, try a light "polishing" of the terminals with emery cloth to provide just a little "roughness". I'm still using ancient technology (AGM batteries) but terminal connection resistance is just as real ;-)
Nothing specified for any space around the inverter or airflow. How do you know your torque wrench is precise? Many of the small ones (for low torque settings) are way off. Unless you paid $250 for it.
@@OffGridGarageAustralia Even a less-than-100%-accurate torque wrench is more likely to be in the balklpark than most people's "That's tight enough" - even better, it's repeatable, so you know the torque is the same on all connectors and a small difference in loss is not due to the connection tightness.
I wonder if the bus bars are the problem, changing temperatures will cause expansion and contraction, not too good for the battery terminals, maybe a more flexible conductor would work better for your build.
really keen to know if it can handle 3000w for short periods. two 1500w loads turning on and off at different times such as my induction cooktops. I had a mppsolar 2400w unit which would do it. it would flash overload here n there but never overheated or stopped but i wonder if the victron will shut off? Both my mppsolar inverter 2400w and 3000w don't have a heat derating like the victron. they output full load im told by mpptsolar and only shut down if they overheat.
Yes, it can handle even 5000kW for short periods. When I use the garden shredder or electric chainsaw, they sometimes get stuck and I later can see spikes in the graphs down to -90A for the battery. If you do it too often to quickly it shuts down though.
@@magicmanspaz You got them both turned on at the same time so 2x1500W=3000W or just one at a time? It can definitely handle one at a time even in hot conditions but it can definitely *NOT* handle both at the same time regardless the temperature.
@@OffGridGarageAustralia i'm thinking in my camper. two breville induction cooktops single portable ones. only on half setting but at half they pull around 1500w each when on. they would be turning on and of randomly at mostly different times. my 2400w and 3000w mppsolar would do it. they don't have heat derating they will output full power and only shut down if they reach a too higher temp. i am wondering about the victron. especially in heat with its derating. help me Andy i need an excuse to buy more solar inverters to play with hahaha
I know this video is old but doesn't Victron call for 100mm of clearance around the inverter for full cooling air flow? Restricting the airflow raises temperatures and prevents full performance.
I have a multiplus… I have no plans on running it over about 2000 watts continuous ..If I need more than that I will buy another and parallel them at max 4000….life is all about having headroom…
@@OffGridGarageAustralia I have watch them all, little details that I overlooked, good reason to rewatch. I hope my Eve280 cells arrive soon, it has been just over 50 days waiting. Thank you for your honesty, you have my well earned respect
Hallo Andy, zur Erklärung : S1 bzw S2 ist die Einschaltdauer von dem jeweiligen Gerät. S1 = 100% also das Gerät läuft im Dauerbetrieb - hier mit 2000W. S2 = Das Gerät läuft nicht im Dauerbetrieb ( Wechselbetrieb ) - 2400W ...eine genauere Erläuterung findest du in Wikipedia. de.wikipedia.org/wiki/Einschaltdauer Grüße Werner aus Süddeutchland
Your smartphone and tablet are ALL Class2 Blutooth chipsets. That is specified for a maximum range of 10 meters, line of sight, no obstructions. In reality it is usually 25 feet (about 8 meters). If you want longer range, ALL devices that are communicating must be Class1 Blutooth, which is specified for up to 100 meters. Not used in mass market products, because it is not cheap and not supported in any phone, tablet, or computer.
what if you put the bms balance cable in the centre of the connection bars so they read the same distance from 1 bank to the other the reading you was doing is not the connection that the diplay was showing to show the display you would have to touch battery terminal and the balance lead
The Balance wire in the middle is the better option anyway, and with the use of a serrated conical spring washer you also get a better pressure distribution on your battery terminal. Small details sometimes important,and sometimes not, it just depends on how far you want to go .....
I have the Victron smart shunt 500a. I love the data but Bluetooth sucks for me too! They need to fix this.. My Chinese JK BMS can go 3 times the distance!
PS: Location of the inverter inside a metal box is incorrect. Any airflow reduction will cause higher temp in the unit. Common sense. I was wondering when you put it in there when you would experience this issue.
"It's 6 amps outside", that's a classic Andy everyone will be stealing that one from you.
That needs to go in the shirts!
I absolutely busted out laughing!!!! I know the feeling! What a great guy!
Good video, here in UK weather is 100mA from 100W of solar.
Hi Andy, You might want to clean off the conductive grease you used. I believe that many manufacturers indicate not to use grease for primary power connections (between the conductors, in other words between the battery terminal and the bus bar). Also, it might be that the nuts are slowly turning as you have a lot of temperature changes day to night so that thermal cycling might let the nut spin a little bit. maybe better spring washers, or even a nylock nut to prevent that from happening.
Try checking cel voltage when batteries are at resting .Ias I understand it to be quite normal for cells to be apart at first after the discharge.
I'm sure it's mentioned in one of the almost 250 comments but if you were planning on running loads like that often a small capacitor banks would smooth that draw curve out. As I've mentioned in other videos beside my 400ah banks for garage and home, in my car audio build I use 2-630 farad ultracaps to handle surges and a bunch of lithium feeding the cap banks. It makes for extremely even draw and a whole sh"%ton of peak draw that even the lithium doesn't come close to providing. This is one of my many favorite videos of yours I love seeing things put to the test
Thank you sir for sharing your developing story - I am in the process of setting up a off grid garage. I have learned a lot from watching your channel and I thank you for all of your efforts :)
Great job on the little details terminal to bus bar in millivolts . Thank you for this knowledge of the information you bring to the RUclips audience. Your cabinet I think you need to install a fan temperature control to get the best power consumption out of your unit due to the heat.
Thank you Wayne. Fan installation is coming soon.
Love it! Its 40amps out! You should make that T-shirt!!!💥💥🤘
I am SO envious of your beautiful property. If I stick my arms out of my house windows, I can almost touch my neighbors house. NYC suburban plight
Oh, wow, we love it out here, got 10acres of beautiful Australian land with lots of wildlife and.... space.
@@OffGridGarageAustralia I am within 30 min drive from an amazing beach......Plus I was born on this sandbar...It's home
Thanks for this video. I always suspected that Victron are not designed for hot climates. Your video just confirmed this.
They are designed for a range of environments the highest Watt rating is rating is at 25C ambient though.
16:30 VA(power factor, usually 0.8) and W are not the same. You have to multiply VA to 0.8 to get the real Wattage. 3000VA*0.8=2400 W witch in your specification is verry acurate.
The S rating on the shredder is service factor. S 1 is the maximum continuous load. The S6 is the maximum it can do but only for 60% if the time. Most machine tools are rated like that as it allow manufacture using a smaller motor.
Am envious of your high end equipment. I do similar experiments but with lead acid battery and Chinese electronics!
Please look at the space requirements for the inverter. The electrical cabinet is going to need ventilation if you want to use it at higher loads.
Yes exactly.vent holes in the battom and top of box . Your are a great asset to all of us thankful to you
Sharyn Comstock, I would suggest cabinet exhaust fans be used controlled by a din-rail thermostat. Positive air flow will be much better than passive ventilation.
I see two things that I question.
1. Put a big hole in top of the case and duct an exhaust fan to get more air flow past the inverter. Thats your only option besides getting a bigger inverter that is in range for the temperature.
2. In your diagnostic at 21.22 some of your bus bars appear to have large holes, and it appears the grub screws and washers are of different materials, which pulling high amperages could cause a problem. If that is the case you need to maximize the surface area of the cell terminal in relationship to the bus bar. The bus bar, even though heavy still acts as a fuse and if you could pull enough amps would fail.
*** Always love your videos Thanks ***
Hi Bob, as I explained in my newest video, I don't need a bigger inverter and theses are corner cases I'm testing here.
All bus bar equipment is stainless apart from the terminals and bus bars themselves.
Why is so unknown to everyone inverter spec is for 20C degree. Over 30 you get roughly 75% top close to 40 under 50% only without overtemp. Surface temp is absolutely not even close to internal when you get that inside it is around 80C degree internal , it switch of close to a hundred. I tried to tell somewhere back in time but unlikely read that. That incredibly hot climate simply just take a double on a desired number. This why i also wrote the cabinet is completely unnecessary for that climate. Nice to see the experiment, i like it very educational. Nice garden!
Thank you.
You are on the cutting edge 👍👍
I love it " Its Sunny outside about 6 amps" sooo true, my wife looks at me funny when I say things like that lol
When gutters creak, I know I'm getting 12amps
Your videos are very detailed and informative . Thank you so much for that . Regarding the inverter ratings , VA is the apparent power not taking the power factor of the load into consideration . Kw is the real power taking the Pf into consideration . Most AC generating devices are rated at a PF of 0.8 so your 3Kva inverter can only give 2.4Kw
Cheers Ross
Hi Chuck, I think you mixed this up. It's the other way around. VA takes the PF into account and can therefore be higher than the actual W. Your own example is correct though 3000VA apparent and 2400W real power.
I think by polishing the terminals, you made them so smooth, that the grease is now evenly spread between the layers. If they are not smooth, the small elevations and grooves will be pushed "into" each other leaving the grease in the "gaps".
It seems like some movement is occurring with your terminals with high amp loads, the terminal Grease maybe increasing the movement. Batteries could be expanding a little bit, try cable busbars and see if it helps.
Make crimp conections with two lugs and cable change the rigid bus bars and measure the voltage .....make video and compeare....
I have same issues with my cells as well....
Excellent job....spot on ...👍
What is your finding with such a setup? Does it make a difference?
Honest....i think rigid bus bars are fold that u dont have proper fit to cell terminals....u have to consider that not every cell terminal is made so acurate by and if u have
I have bus bars made thin cooper 0.5mm and one bus bar have 7those cooper strips bonded together with heat shrink tube so i have dismantle bus bars and use only two cooper strips in one conection...
On 100A load no heat at all....
is worth to try and u wont stres the battery terminals ....
Andy, minor cell voltage deltas are quite normal. I find that it is common to see cell voltage deltas of up to 30-40 mV when running at higher current levels. I don't think you have a major issue here with cell voltage discrepancies at the load levels you are running at. Just be careful not to tighten the connections too much. The more you tweak the terminal connections, the higher the probability that you will strip the terminal threads. Then you will have a problem.
I second and third this on the terminal threads. You are going to worry your way into a bigger problem. Love your videos.
You can get a wireless Bluetooth range extender to connect to the Victron kit. If you put it near the window you will be able to connect when you are in the garden. It is mains powered, but you have solar to take care of that.
Of all my Bluetooth devices, my Victron Controller's signal is the weakest. Ian H, what Bluetooth range extender is available that would connect to Victron Controller? My searches just find extenders where a 3.5 plug is involved, like a speaker output.
Andy, stainless steel is a poor conductor. Until you use a brass stud, washer and nut with a spring washer you are always going to get mixed results. The elongated hole in your busbars is also giving different a contact area resistance dependant on position. You need new all copper busbars and the BMS connection needs to be moved off the terminal and directly connected in the middle of the busbar.
I thought about longer set screws so I can have the balancing cables connected with a second nut.
@@OffGridGarageAustralia I have that setup, and works good.
Indeed, stainless steel has a high Internal resistance, so bad for electricity.
Good news is that you don't need / want that to do the work, the bus-bar to terminal contact does that.
Don't worry about contraction and expansion, it's a tiny piece of tinned copper, fairly flexible with 4Nm Torque. A few mm difference between 2 terminals is easy corrected by its flexibility.
Terminals themselves are in special housing that is build to buffer for the micrometers expansion/contraction.
Very interesting connectivity issue!
Hi Andy. One of the best things of your videos is that make hundreds of people arround the world to think about your problems and projects :-)
My thoughs about two thighs:
1- the thermometer gun you use, (IMHO) I think is not used correctly. The laser dot is just a POINTER showing the TOP of the AREA the sensor is reading. Such surface AREA size DEPENDS of the DISTANCE beetwen the sensor and the surface. Think it is like a light torch that iluminates the surface according with the distance. At one meter, the reading is imprecise since is the "average" of a BIG surface (and not in the red pointer at all).
2- the voltage drop in the studs has to be studied carefully. Using grease just make the problem worse. The main contact area is BELOW the Bus-bar (the "terminal" itself); is the flat metal surface where the stud is inserted. The nut and washer material is almost irrelevant (but the diameter of the washer not). The most important factor is the flatness of the "terminal" and parallel to the bus-bar´s lower surface (more than cleanliness, plating purity, and so on). Dilatation is an issue, so, in my opinion, "omega" shape is much better than just flat, and even much better a flexible jumper. Aluminium is very reactive metal and is oxidized almos inmediatelly in contact with the air (ask to any welder about why it is needed to use argon arroud for welding aluminium), and aaluminium oxide is not a good conductor. Touching again and again the nuts is not a good idea, since it stresses the stud and its anchoring inside the terminal, damaging also the metal surfaces (coper and aluminium are very soft) and making necesary to repeat the tightening for ever. I sugest the use of conical washers (spring washers) that makes a constant pressure adapting automatically to the temperature induced dilatation.
Thank you for your thoughtful comment. Very good point. I will use a FLIR camera soon for these sort of tests. Hope it gives us better results. The gun is just an approx, easy to grab and shoot.
Try a washer between the terminals and bus bars . Copper or aluminum may give a better contact .
When I worked on aircraft I think we used tin plated brass washers. So long ago I can't remember the galvanic properties, but you may have a point. 👍
Overall it's conciddered bad practice to put anything between the busbar and terminal except antioxidation compound.
The last is in many variations from di-electric grease to special silver based paste.
The bus-bar is coated, so it isn't copper to aluminium.
I used to polish my terminal everyday, when I was young, almost never anymore...What a drag it is getting old...
I bet your terminals expand when pulling high currents. Get some expanding washers and torque connections down when warm. Or maybe the plated copper and aluminum don't mix for connections. Try aluminum busbars. Or maybe just a few busbars have bad plating.
Interesting what's going on with battery connection / bars. Don't think stainless is a good conductor from memory, go for copper and look to see what they offer to go through oxide layers.
I remember Oz! Gets hot during the day, so if charging at night look to vent, maybe from outside air through a bug screen.
Need fans and remove that hot air.
Keep on charging.
Mark
Only the stud is made out of stainless. This does not conduct much power. 99.99% will go from the terminal area to the busbar directly. The stud and nuts only push them together.
Andy, what about lapping the terminals, by applying light pressure with the nut and lapping compound between buss bar and terminal, while turning back and forth? This should make sure that the buss bar and terminal have maximum contact area.
Hi Andy i'm from Portugal and i love to see your vídeos. But i have a question: why didn't you bought a 5k inverter?! For your needs i think its a better choise.
Andy, vielen Dank, Top Videos wie immer :-)
There is anti-oxidant paste designed specifically for electrical connections to aluminum which prevents aluminum from oxidizing. That's likely why you have to periodically loosen and tighten nuts to scrape oxidation off.
I used it as shown in the last video.
With regards to the inverter I think that the learning point is to over spec by at least one level. I use a 10kw inverter for a 7.2kw car charger. If I run a kettle at the same time it copes (9.5kw) but brings on a warning light. Not a problem for intermittent use but I keep it to 7.2kw for continuous use. Probably good to choose an inverter so that it doesn't run continuously more than 75% especially in hot climates. As the Victron equipment has covers over the terminals I didn't put the inverter inside a cabinet which allows better cooling.
Andy, I have following theory: you should not care about the potential at the bolt, what is important is the potential difference between the aluminium pole of the cell and the busbar and also the ring terminal of the BMS. I think, and again that's just a theory, that the problem is created by the stainless steel washer which is placed between the busbar and the ring terminal. Remember that stainless steel has a lower electrical conductivity than copper.
Well, that's exactly what I measured. The stud IS the terminal. It's threaded into the terminal so should have best contact. As other terminals show, they have 0mV so there is very good connection. The BMS connection is not so important because there is no current going through. It's just a voltage sense.
@@OffGridGarageAustralia If there is no current going through the BMS connection how does the BMS balance individual cells?
@@OffGridGarageAustralia I think the voltage drops you measured has convinced me to redesign the way I'm going to connect my terminals to (hopefully) avoid such problems... to either solder (or clamp) all wires to one ring and tighten that ring to the terminal (like the positive battery terminal is designed in a regular automobile), or if I do use busbars, I'll drill a small hole in each busbar for mounting the BMS sensors.
@@charlesrichards5389 that's a good idea, Charles. I'll put the BMS balance on the busbars too at some stage. It just makes sense.
@@OffGridGarageAustralia Now that my 16 (176 Ah) cells have finally arrived (I'm now in the process of top balancing them) I just have to properly use what I learned from here (and other great channels here in the YT-DYI-PV community).
I want to give it a try by using copper washers istead of stainless steel ones. Let's see if that brings any improvement. I have already observed this thiny drop in voltage during my capacity tests. By tightening, the shown Voltage, at the capacity tester, increased by about 10mV.
At this time I intend to use the busbars which were delivered together with the cells. I will use, for the beginning, only a maximum of 1 kW for charging and discharging, so they should be enough (my system is AC coupled so I have all the parameters under my control, I hope at least).
In our Data Center we use 220V fans in the cabinets, They make a bit more noise than you are used to from a computer fan, but blow like a tornado, but watch out for your fingers, I also use them myself in my cabinet ..
I wonder if those bus bars you use are made of copper or secretly not made of steel, if your cells are not exactly the same height, it will never connect well, copper forms more easily, so mayby.....
Nice test .....
Now 5kva inverter would work without any problems ...your high enviroment temperature it makes more difficult to work ....
I would calculate normal load +30-40% because of high temperature but already know that...
And because is free power eventualy u will add more load to the inverter and max out the output or work on max whole time...
Like the videos .....
U hit the common problems spot on...and not many do that ....many questions are that way answered...excellent....👍
Reference your busbar/battery terminal problems. I wonder if the top of the problem cell terminals are no longer absolutely flat. Perhaps polishing them caused the top to become curved? If so this would reduce the contact area. I am not totally convinced that the conductive grease is a good idea. If it has slightly reduced conductivity it may actually be impeding rather than helping. Blocking direct metal contact maybe worse overall than helping to make up for the microscopic gaps. If the surfaces are totally flat and reasonably smooth the contact resistance should be minimal. If you are worried about corrosion you could add grease afterwards to act as a moisture barrier. I use thicker aluminium busbars with no grease on a pair of 12v LiFePo4 batteries in my RV. No risk of dissimilar metal corrosion and so far no problems.
Kind of sinister when you think about it... In the winter, inverter will provide a lot of power, but solar won't. In summer, you will produce a lot of solar power, but the inverter won't let you use it all.
I think you just need to get used to it and adapt, use the energy wisely. But yeah, you're absolutely right.
@@OffGridGarageAustralia Just keep adding storage....More capacity=empty wallet
@@KD2HJP Actually, I wish these cells were available when I did my solar system about 18 months ago. Instead of 4 Battle Borns for 5120Wh, for $4k, I could have had, in the same space, with a little more weight, 14kWh of energy for half the cost. Oh well, I still love my solar (540W), inverter (2500W), lithium system in my RV. It has freed us from the tyranny of the generator!
@@daveduncan2748 I just picked up 48v Gyll 100 AH pack. I have been experimenting with several LiFePo4 cells, for years. Whilst watching Andy over the past several months, and hitting all the same obsticls, I have thrown in the cheap towel, and spent a few bucks more for my sanity. Can't be happier
Hello! Andy, again, use Nordlocks on the connections. Keep "cranking out" videos !! Thank you.
Victron inverter is world class, i am more impressive to your installed BMS and DIY busbar
Yesterday in sunny Melbourne my 48 volt batteries were charging at 67 amps. And no rain here also.
67A is very nice weather 😁
I would like to advise you to check the data sheet for this inverter on victron web page. Continuous real power at 25 Celsius is 2400W. As the current draw for inverter at the terminals raise, the internal temp will also raise ... so youre gonna be working at >2400W. Always size your systems with buffer and consider the real power with ambient temp
.. just giving some technical advice.
my bad .. you covered that in the video however .. a 3000VA inverter doesnt mean run at or above 3kva, thats apparent power so you should work with the 2400W real power
I couldn't help but notice something about your voltage drop:
When you measured between a terminal and a bus bar you had it, but when you measured between a terminal and BOTH ring lugs, you didn't.
Completely crazy theory here:
Could it be, that between the terminal and the bus bars there is a difference in plane, that they are not absolutely parallel to each other? Would explain the behavior you have.
If it weren't so much work, I would suggest to change the bus bars for cables with ring lugs, so you can avoid any angle related problems.
Maybe you could take that to mind and consider it as a last resort, if nothing else helps. Maybe you could exchange the most bothersome bus bars already and look, if it makes any difference. If yes, you could do the other ones later on.
You need to remember: The bus bars are ONE flat piece of metal. In this case, with this short length between contact points, it doesn't like to bend and twist very much, copper or not. With a piece of cable with ring lugs you do not have that problem, as the cable is made of flexible strand material.
(I would have written that in German, but didn't want to exclude the international viewers.)
I think you're onto something. I wish he had measured for a voltage drop on his inverter lugs too.
Andy, There are some things that need to be cleared up. Your inverter is only rated at 2400 Watts. The VA rating is not watts it allows for .8 power factor which accounts for the magnetising current of your motors. I realise other viewers have tried to get this across, it is an important fact to know and understand. Total VA rating is Watts (true power) plus Volt Amps Reactive (VARS). VARS are necessary for any AC magnetic device to operate. The grid is designed to operate at .8 power factor.
Now having said that, you will do well to get rid of the box, once you arrange proper air circulation the inverter should run happily enough at 2400 Watts and up to 3000VA.
My set up is a pair of Giant brand 4000 Watt / 5Kva all in one units connected and programmed in parallel / load sharing. In theory they should start a load up to 20Kva (approximately a 5 KW motor DOL) on their own, without mains support which they can be programmed for. They will run welders.
The installation / user manual gives strict mounting instructions especially around airflow. They recommend wall mounting with 500mm above, 200mm each side and 500mm below for 55 Deg C ambient.
This afternoon 64 x 310AH CATL cells, when they arrive I will see how they go. This to upgrade my system from AGM which worked well but has limited cycle availability.
I have already taken a variety of Bellville washers into stock for the upgrade project.
In case you don't already know Belleville washers are conical springs that spread the force to their rim which can give up to 10 times the effective contact area. I am also considering hardened washers for their electrical contact spreading properties.
I also have in stock Utilux H2397 Electrical Jointing Compound (Aluminox) which is certified for jointing of Aluminium electrical connections.
The reason my choices are so damned conservative is 48 years as an industrial electrician working with Megawatt class inverters and heavy DC.
I will be interested in how your contactor based BMS goes over time. In industry DC contactors are the single most expensive electrical maintenance item, so expensive if fact that on mobile equipment only tyres are more expensive. They are now superseded in new equipment by IGBTs and each day more legacy fleet get retrofitted with IGBTs. Regarding the issue with your Charge controller losing its marbles, I would start at that relay.
Your balance lead connections are not at the standard I would accept. Trade quality "Copper Grip" lugs with larger palms are available. When I do mine I will drill and tap the busbar for the BMS connections which will be easier.
Do not use cheap "Vinyl grip" lugs. The copper grip design has a double copper sleeve which forms the correct crimp. The cheap crap is for decorative purposes only.
Your videos provide little nuggets of info that i don't see anywhere else. ie: toghtening a terminal while viewing the BMS readout. Have never seen that. But, it is relevent!!! Also. How about the crimp of the terminals for the balance leads? Perhaps some are not tight?
6amps outside. Love it. Hilarious 😂😂😂😂
Put a soft start on an outlet that you run loads that have a burst current like this.
Try copper washes, and make your own bars with ½" copper tube. For the over temperature give them more space in between they are too close to each other.
That's a very hot temperature for an inverter, I doubt my radian would handle full load in that kind of heat either. It may but it would be running at max temp for sure.
Yeah, it gets hot down here in summer time and I have to throttle down the power output of the inverter.
I would move the inverter to the floor. It will be cooler down there. Because of the case you have it in you may need a full time fan.
The inverter is just to small,and yes,the box where it is inside is to small,put it outside or drill 80mm holes and extra fans,I like your experiments very much 👍those batteries have to small fixings there are batteries with M8 bus bar connections
The inverter is not to small for my application. I only have the irrigation pump with les than 900W. This was to test overload and overheat function of the inverter so I know what I can expect in this climate.
@@OffGridGarageAustralia oké no problem's then,but keep it cool
A suggestion: try replacing the nuts on the terminals with nuts having flanges of slightly larger contact area
I've ordered some busbars to connect this all together. The inverter terminals are not designed to take more ring lugs.
interesting to note.... hadn't considered the the limitations of a hot summer day. is the box you have it in limiting air flow partially? some temperature control computer style fans on the top and bottom of the box would be good I'm sure.
That's exactly what I'm going to do.
@@OffGridGarageAustralia Papst 4650 N Axiaalventilator
I would use a zinc-coated Internal or combination lockwasher. That way any movement from heat expansion is negated from the bite, or bites if combination washer is used, upon application..
This problem does not come from heat expansion. The batteries and terminal stay cold all the time. Even during hot temperatures during the day the cells itself are up to 10° colder than the ambient temp.
try to attach scrounging discs to the bussbars, preferably copper ones, oxidation can be prevented with pole grease
My EASUN 48V/5KVA inverters capable of twice that power for 5 seconds never have the slightest problem in starting and
running a load like my air compressor AC induction motor which takes more than 25A startup current @230VAC, provided my lead-acid batteries are charged! The first of those inverters cost me only 500 bucks until I wanted another six of the parallel version @ $1100 each, delivered promptly by the Shenzen manufacturer for my purpose of a 3-phase 30KVA system.
The chipper shouldn't be started with sticks in it. They always trip breakers with sticks in them. Long low current extension cords take away starting power. Try with a higher rated extension cord. An outlet on the outside of the garage would come in handy.
Told you that would be a hotbox and you needed forced ventilation
I added also a 11cm diameter hose with an active ventilator in it under my EAsun all in one inverter right under its 2 ventilators to catch its blown out hot air to lead it outside the technical room it resides in. Would become a sauna otherwise. Also added 2 pc fans next to the intake holes of the inverter to make a stronger wind flow going through the inverter (controlled by 38 degrees temperature switch, so only active when needed)... helped a lot. pc fans are hooked up to the 51.2v battery via a step down buck converter to 12v (all cheap on AliExpress)
Do you have a washer between the balance leads and the bus bar / inverter cable? The screw, nuts, washers, etc. should not be used as part of the electrical circuit. Threads and stainless steel, not good. They should be considered as part of the mechanical force holding the highest current component against the battery terminal with lower current components stacked on it and compressed by washer and nut.
It's like I'm going back in time.
I have the same issue on my Lishen 272 battery pack with the resistance on the packs changing, I think it might be related to expansion of the cells when charging / discharging. I am thinking of trying to temporarily clamp the cells with kapton tape to see if that stops the movement.
I have space in between my cells so they can expand (which I have never seen actually). I think it's purely oxidation related. I've ordered some other ant-oxidation paste and will try this out on these terminals.
I went two times the size for my INVERTERS for my cabin and for my camper than I need so they don't have to work hard 😎👍🇺🇸
That's what I did. Usually the max load is around 900W. But you need to do some testing, right?
I had a new lifepo4 battery that the surrounding plastic around the terminal was higher then the metal terminal post itself by about 0.5mm, I had to use a sharp knife to trim the plastic away from terminal post.
Uh, what? That sound wrong. Where did you get this battery from?
@@OffGridGarageAustralia basen.en.alibaba.com/ I have brought many batteries from them over time, what brought it to light was a very hot busbar, checked that the bolt was tight, which it was, but on removing the busbar found the metal post was below the plastic surrounding it
just a tip: if you are measuring temperature with the infrared thermometer always go as close as you can to get the most accurate results, for example if you are 30cm away then it measures the average temperature of a 30cm circle approximately, so if you get close you get more accurate results
I just bought a thermal camera. Well worth it.
I think it's pretty simple, the busbars are too rigid and the expansion off the cells makes the connection move around and make inconsistent readings. You should use copper flexible stacked thin sheet busbars. Also don't tighten the nuts without holding the screws that go into the battery, you could be pushing a bolt into the cell like this.
The cells have space in between them. Even if the would expand, the bus bars won't move. I never tighten the nuts without holding the set screw in the middle.
@@OffGridGarageAustralia according to the specifications, the cells should be compressed together. This prevents delamination.
Look at it like a phone book on its side.. that doesn't stay good long time :-)
Contraction/expansion is micrometers, the terminals are in "soft plastic" to compensate for this.
As I use tubular wrench, I can't hold the studs.
Instead I used locking agent to fixate them.
I could not see any ventilation in the box with your Victron equipment. I presume the door is normally closed. Is there any ventilation with the door closed?
I have the same shredder. It says "silent" but also "93dB". Figure that out.
what are your bus bars made of ? they should be nickel plated copper. dont use aluminum oxidizes instantly
IIRC, the battery terminals themselves are aluminum, so he needs to use anti-oxidant paste for electrical connections to aluminum conductors. Otherwise, the aluminum will keep oxidizing and need periodic loosening-tightening to scrape the oxidation off.
Hello Andy, i have a question. I've planned to buy a Solar 6000 EP. but i realize the inverter is not so far in the setting, we have only the possibility to set :1.Battery Type
5.Max Charge (A)
2.Battery Capacity
6.Max Discharge (A)
3.Nominol Bat Voltage
7.*Discharg Depth
4.Battery Cell Type
DOD.
Do you think it will work with the custom 16 cells batteries with the JK BMS ? we cannot set the absorption or float with this, and Victor is not really the same budget to set a 6 KWh inverter ! Thanks a lot for your help and nice videos !
I know you're set on a closed box with no noise or ventilation but that inverter relies on good airflow at all times. To keep it in that enclosure you're going to have to cut two 120mm openings for two 120mm fans, one intake at the bottom and 1 at the top to have any hope of keeping the inverter operational. If the inverter were mounted outside of an enclosure it would probably give you full wattage.
Are you absolutely certain the bus bars are pure nickel-plated copper or aluminum? Consider buying some pure copper bar stock from www.onlinemetals.com - I did that and constructed my own .75 inch x .125 inch thick bus bars that run cool as a cucumber (or night frog in your case ;) )
Using copper ring terminals as opposed to the questionable (tinned aluminum?) version you have would probably eliminate the BMS reading problem
Keep up the great videos!
maybe try removing the grub screws and putting the conductive grease on the threads before reinstalling them on the batteries?
Trying to think into the future a bit, if your hunting for fans. The 120mm Delta fans are awesome to cool things down I upgraded to them a few years and wow they make a big difference on the equipment over-temperature problems. So looking into the past and bus bar ideas look for the flatter bars with rounded ends. Nickle plated copper ones the there are multiple lengths available on aliexpress. I would also suggest using a torque wrench so that they are all exactly the same. Now really not sure the small differences you are seeing is much to worry about maybe can set the alerts to something less perfect. Seems like there may be a point to stop and be happy with it.
120mm deltas are monsters :-) tremendous amount of air pressure and high volume.
Sadly.. LOUD!!
I switched my deltas for "silent wings 3" what is for noise level a lot better.
They don't give the amount of flow or pressure, but a few of them will do the same, at same or less power usage and they last +30 years.
The small difference he sees is really something to look at.
If you have LiFePO4 cells you know.
And Indeed... Torque wrench!
Adviced is 4Nm on the nuts of 6 mm headless bolts. About 350kg pressure.
I just bought a digital Torque meter that goes in-between for this purpose.
Really difficult to feel by hand the exact torque!
@@frankfromthailand2190 Yes need to use a fan controller with Deltas they last forever well they are made to last and nice and quite idling along and as is gets hotter they have the power to cool it down.
Andy, as far as the loss between the bus bar in the battery, you may want to use a torque wrench and torque the connection to the factory specifications. That may help?
I haven't got one and don't want to spend $250 one a working torque wrench. The cheaper ones are most likely not working correctly and showing random torques when compared to expensive ones.
With the set screws now, The torque can be a lot higher than as with the screws before.
Search for digital Torquemeter
The one I bought was about $35,- and does 1.5 to 30Nm.
(1/4 inch connection)
They aren't as exact as $250- kind, but fairly accurate.
It does help making all the nuts the same torque, minimize the variables for errors.
Obviously, terminals and bus-bar needs to be clean, fat/grease free and as free from oxidation as possible before installing.
Di-electric grease or ox-gard helps with the oxidation prevention
I was just about to ask you if you tried to measure cell voltage with your voltmeter and comparing them to what the bms is saying, I like the Idea of swapping bus bars, are they the same cells you were having issues with before you polished them?
If you really want more fun I would top balance again, and disable the bms balancing and see how balanced the cells remain after a couple of midrange cycles, but I know you won’t be keen on that because of the amount of time it will take.
ribbit! told ya so ribbit. LOL pull cold air from concrete floor , put fan top left cabinet. ribbit!
Interesting thank you
Sold I want one of those electric chippers. Heat is our enemy for sure. lol Use the metal siding for a heat sink and turn on the sprinkler hose on the outside of the garage. Copper bus bars with the bms lead soldered on may take some of that away.
We await your solution Cheers.
Did you put you some grease on them terminals otherwise the oxidation will keep doing that especially in your climate those are not LED they're aluminum
"A quick tick with the spanner and it's fixed. But what is the solution?" - it sounds like you have a thermal cycling problem, which means you have a current heating problem. you can change the geometry of the busbar connections so that the pinching direction is shorter (the terminals are flatter - thermal expansion/contraction in the pinching direction is smaller), or you can increase the overall cross section of the busbar (increase cross section, reduce resistance, reduce heating), or you can do both (best option). you can try spring washers, but they'll just reduce how often the issue becomes a problem, and it sounds like the geometry isn't great and the busbar is undersized for the current you regularly carry. i'd make the busbar more beefy.
note: adding multiple parallel busbars is the same as increasing the cross section of a single busbar.
Exactly, what is the solution? I don't think it's thermal problem. 60A is not that much and that's all I'm pulling.
@@OffGridGarageAustralia 60A isn't that much, but I'm not sure how thick your busbar is or how hot and cool it gets each day. If the connections keep going bad over time, and you keep having to tighten them back down to correct them, it's almost always because of thermal cycling - when the busbar gets hot, it expands and either it or the bolts deform just a little, or it might cause your securing bolts to back off a bit. When everything cools back down, a gap is left that causes the connection to be intermittent, or the bolts slowly get loose and eventually the connection turns bad. You can try serrated locking bolts/washers, but they tend to just extend the time period in between tightenings.
I suppose you could solder all the bolts to the busbar - it'll take a lot of heat, but the thermal cycling likely won't be an issue anymore. Even so, I think it's better to increase the cross section of your busbar to decrease its resistance and thereby decrease the current-heating caused by the resistance and the current flowing through it. Maybe as a test you could bolt on a heatsink to try to keep it from getting hot - if that at least partially cures your connection degradation problems, then you know the issue is thermal cycling, and you know one way to correct it is to increase its cross section.
Another test would be to hook up a thermal sensor to the bus bar so that you can measure its temperature throughout the day, lets say for about a week. That way you can quantify the extent of the problem. In any event, the title of your video is extreme heat - if the electronic equipment is getting hot, it stands to reason the busbar is getting hot too.
@@kevinwhite9919 Yeah, nah, there is no heat at the terminals or busbars at all. All feels cold. I checked them a few times with the thermometer gun.
@@OffGridGarageAustralia as long as you're checking them when they're being used, then i guess it's something else. the locking washers or soldering would be some options. could the crimp joints at the lugs be wonky at all - anything mechanical near the bolts you tighten down? is all the metal copper, brass, or solder?
@@OffGridGarageAustralia Looking at your perfect battery connections I really think you are barking up the wrong tree!
Possibly put a heat shield on the outside wall of shed to keep sun of wall. Try standing a sheet of iron for a trial.
Could here your frogs in the back ground 😎👍🇺🇸
🐸🐸 Yes, whenever they hear me talking, they start talking as well
Serrated flange nuts are large diameter and apply pressure at their circumference. Perhaps your bus bars and/or terminals are slightly dished?
Bus bars actually only make true contact with about 5% of the area of terminal - and that’s for a perfect joint.
Conductive grease is not actually conductive and cannot help improve the 95% area that’s not making full contact.
Conductive grease introduces another metal (e.g. copper or zinc into the aluminium / nickel joint which can promote corrosion - particularly in a marine environment - and is therefore not recommended.
Dielectric grease is used for un-plated copper busbar / terminal joints because corrosion can occur in the 95% copper not in intimate contact with the terminal; however aluminium terminals do not need grease as their oxidation prevents corrosion.
Try serrated nuts and clean, dry and tight joints for consistent low resistance connections.
Perfect 👍
Overheating: How much space does the manufacturer specify around the inverter case? How much airflow (m3s or cfm) does the inverter need? Does your cabinet have enough filtered openings to allow that much air in and out of the cabinet? I'd say build an Arduino or similar temperature monitor that drives a display of "Do not exceed XXXX watts." based on the inverter case temperature.
Terminal voltage drop: Did you use a torque wrench to tighten the connections? I bought a small (in-lb) torque wrench to ensure that the battery connections were tight enough. If proper torque doesn't resolve the voltages drop, try a light "polishing" of the terminals with emery cloth to provide just a little "roughness".
I'm still using ancient technology (AGM batteries) but terminal connection resistance is just as real ;-)
Nothing specified for any space around the inverter or airflow.
How do you know your torque wrench is precise? Many of the small ones (for low torque settings) are way off. Unless you paid $250 for it.
@@OffGridGarageAustralia Even a less-than-100%-accurate torque wrench is more likely to be in the balklpark than most people's "That's tight enough" - even better, it's repeatable, so you know the torque is the same on all connectors and a small difference in loss is not due to the connection tightness.
I wonder if the bus bars are the problem, changing temperatures will cause expansion and contraction, not too good for the battery terminals, maybe a more flexible conductor would work better for your build.
YES, I replaced the busbars now and guess what...
If the external inverter temp is around 42 deg C the internal temp at the FETS will be in the 60 to 70 deg C
Yes, most likely.
really keen to know if it can handle 3000w for short periods. two 1500w loads turning on and off at different times such as my induction cooktops. I had a mppsolar 2400w unit which would do it. it would flash overload here n there but never overheated or stopped but i wonder if the victron will shut off? Both my mppsolar inverter 2400w and 3000w don't have a heat derating like the victron. they output full load im told by mpptsolar and only shut down if they overheat.
Yes, it can handle even 5000kW for short periods. When I use the garden shredder or electric chainsaw, they sometimes get stuck and I later can see spikes in the graphs down to -90A for the battery. If you do it too often to quickly it shuts down though.
@@OffGridGarageAustralia in hot weather say 40c do you think it would handle my 2x 1500w cooktop loads cycling?
@@magicmanspaz You got them both turned on at the same time so 2x1500W=3000W or just one at a time? It can definitely handle one at a time even in hot conditions but it can definitely *NOT* handle both at the same time regardless the temperature.
@@OffGridGarageAustralia i'm thinking in my camper. two breville induction cooktops single portable ones. only on half setting but at half they pull around 1500w each when on. they would be turning on and of randomly at mostly different times. my 2400w and 3000w mppsolar would do it. they don't have heat derating they will output full power and only shut down if they reach a too higher temp. i am wondering about the victron. especially in heat with its derating. help me Andy i need an excuse to buy more solar inverters to play with hahaha
I know this video is old but doesn't Victron call for 100mm of clearance around the inverter for full cooling air flow? Restricting the airflow raises temperatures and prevents full performance.
Can you try load over 2400watt or 3000w or 4000w see if its runn for how long before inverter shut down please thankyou
I have a multiplus… I have no plans on running it over about 2000 watts continuous ..If I need more than that I will buy another and parallel them at max 4000….life is all about having headroom…
Have you considered conducting grease like Jet Lube SS30?
Yes, as shown in the previous videos.
@@OffGridGarageAustralia I have watch them all, little details that I overlooked, good reason to rewatch. I hope my Eve280 cells arrive soon, it has been just over 50 days waiting. Thank you for your honesty, you have my well earned respect
Hallo Andy,
zur Erklärung : S1 bzw S2 ist die Einschaltdauer von dem jeweiligen Gerät.
S1 = 100% also das Gerät läuft im Dauerbetrieb - hier mit 2000W.
S2 = Das Gerät läuft nicht im Dauerbetrieb ( Wechselbetrieb ) - 2400W
...eine genauere Erläuterung findest du in Wikipedia.
de.wikipedia.org/wiki/Einschaltdauer
Grüße Werner aus Süddeutchland
Your smartphone and tablet are ALL Class2 Blutooth chipsets. That is specified for a maximum range of 10 meters, line of sight, no obstructions. In reality it is usually 25 feet (about 8 meters).
If you want longer range, ALL devices that are communicating must be Class1 Blutooth, which is specified for up to 100 meters. Not used in mass market products, because it is not cheap and not supported in any phone, tablet, or computer.
Yeah, I've got it hooked up to the Victron VRM and I can access all devices from anywhere now.
Thanks!
Thanks a lot, Matthew, much appreciated!
what if you put the bms balance cable in the centre of the connection bars so they read the same distance from 1 bank to the other the reading you was doing is not the connection that the diplay was showing to show the display you would have to touch battery terminal and the balance lead
I could do that...
@@OffGridGarageAustralia it has surprised me how a poor connection can stop balance systems from working correctly
The Balance wire in the middle is the better option anyway, and with the use of a serrated conical spring washer you also get a better pressure distribution on your battery terminal.
Small details sometimes important,and sometimes not, it just depends on how far you want to go .....
Are you still using as 230V can you change settings use 240v inverter
I have the Victron smart shunt 500a. I love the data but Bluetooth sucks for me too! They need to fix this.. My Chinese JK BMS can go 3 times the distance!
i was wondering if it is the actual terminals that are moving internally slightly?
PS: Location of the inverter inside a metal box is incorrect. Any airflow reduction will cause higher temp in the unit. Common sense. I was wondering when you put it in there when you would experience this issue.