EEVblog 1390 - NEGATIVE Household Solar Consumption? WHY?
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- Опубликовано: 2 авг 2024
- Dave explains a common inherent measurement problem in the solar industry with having two separate solar power systems and monitors on the one house.
Why is Dave's household consumption going NEGATIVE on both his older Solar Analystics system and new Enphase Envoy system?
And why does the consumtion follow the sun?
And what is the easy fix?
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That fuse box is the epitome of "Good enough for Australia"
Yep... says it is new, '80's'... Solar wasn't even close to a thought of a fart in the designer's head.
Was the Sparky Chinese by any chance, because that looks more like chabuduo work.
@@wobblysauce that doesn‘t have anything to do with solar. That‘s simply janky improper wiring.
It looks like individual red wires must be run to lights and outlets, not like romex here in the states where all the wires are in one cables. That breaker box is a ducking (to use a facebook term - lol) rats nest! I though my 200 Amp panel was bad with all circuit slots used up.
@@Daveyk021 the cables to the circuits for lights power are run in one cable, Active Neutral Earth with Thermo Plastic Sheath(TPS).
They used to be run way back in the first part of the last centu in steel conduit with individual condutors but thats gone thankfully along with the VIR cotton insulated wire! (Avoid buying a house with that stuff as you will need a full re wire sooner rather than later)
The circuit board is not ideal but normal espically when it gets added onto with solar, AC, off peak power, etc.
Over here in the Netherlands we solved this problem by not having any sun to begin with.
It doesn't prevent Provinces and municipalities from putting solar panels in roads at every occasion.
Or perhaps they figure that it doesn't matter if the panels break and/or the concept is flawed, because they are not going to generate power anyway 😉
solar fietspads ;)
@@gravityskeptic8697 "GRimy"
I hope youre wrong, I’m getting 10 panels with enphase this week.
@@jeroenlodder5838 I'm in the UK, so same weather as you, just an hour or so earlier, and my little 4 panel enphase test setup has been giving me over 5Kwh on the sunny days this week.
Today the weather is horrible, but I've still got 2.5Kwh from them.
I hope you're getting a battery or have a good buy-back scheme in NL, as you'll easily exceed your consumption with 10 panels.
Aussie fuse boards look absolutely terrifying!
I'm amazed the country isn't on fire more often!
at least we dont need two sockets to get 220v
@@alch3myau LOL, assuming that's some dig on the US it's one outlet and it's 240 volts.
I was thinking the same thing. Man ohh man would that not pass any legit inspections in the US.
@@jeffm2787 damn right its a dig. 220v is where its at!
@@alch3myau Someone's been watching Electroboom.
As we say in italy: "The shoemaker has a hole in his shoes". That box is simply nasty!
Yea, that really does look like a MIcky Mouse hack job. All of the breaker boxes I have ever seen have big bus bars that the breakers lock into to connect to the upstream feed rather than just bolting them into a big bread board with wires going everywhere.
Yeah, except in this case the shoemaker couldn't do anything about it because he's not a licensed sparky and it's impossible to become a licensed sparky in AU without doing a 4 year apprenticeship.
@@SomeMorganSomewhere Can't you do the job yourself and then have a licensed "sparky" come along and check? At least in Germany it's possible that way.
@@phillipsusi1791 true. Simply horrible.
@@baldebaldemord9588 not legally.
We're technically not even allowed to install PVC conduit for electrical cables to be installed in because that's "electrical work".
That being said you might find yourself a friendly sparky who may be willing to sign off on it as their work, technically illegal for them to do that though.
That fuse panel, i'm speechless. Amazing that it's legal to have that mess.
As long as the bare live wires are insulated with some high quality asbestos it should be fine.
That "switchbox" looks like a 1950's radio! Has Big Clive seen this video yet?
Wow, that fusebox made me wince.
...situated outdoors in a rickety box no less. Yikes!
It helps that the weather is always dry and hot.
Dang that panel is a mess! Would love to see you rewiring it
BarbasBandas 666 , In the USA, we have local laws which are excruciatingly pedantic about how power panels are constructed and installed. This would be horrific at this level here.
@@BruceNitroxpro here in Portugal you see this type of instalation on pre 1950s buildings.
i doubt that you see dave doing this... because if he is doing this he goes to jail... you need a propper licence to do any work on power in Australia... even when mounting a plug to a cable.
@@emmoemminghaus6455 I was suposing he had a license. My bad
@@barbasbandas6665 hard rules in Ausi-Land... if such rules are made in Germany i would be in jail for the rest of my live.
(Neither have a electronics or a electrican licence)
Short answer: Everything's upside-down in Australia
It's upside down and backwards too, right?
@@fredygump5578
I mean, kangaroos. Nuf said.
Forget onions! That distribution panel makes me cry quicker!
Reminds me of US substation panels from the 50s. 😭
I wonder if the induction monitoring clamps report the wrong current because there are sooo many wires everywhere that generate random magnetic fields.
Seriously! Fix. Your. Damn. Breaker. Box. For gods sake an EE, so much modern power generation and a breaker box out of an horror cabinet. I thought only in the US are such sloppy installations common. But hey lets add parallel current transformers instead of getting a proper breaker box..
... oh boi, if I were the insurance company for the house and saw that video, I'd tripple the rates
@@berniwa that's probably why they have to have their braker box outside. Jesus Christ...
The Aussie fuse boards wiring looks hunky-dory to me. No DIN rails, no distribution boxes
As commented on previous videos... DIN is very much the norm today, Dave's panel just was never modernized from the 60-70s or around that time..
@@rkan2 maybe so but it keeps freaking me out.
Wrong adjective? "Hunky-dory" means fine. May I suggest "how ya doin'"
This video was maddening to watch. It's obvious what the problem is and it took you 15 minutes to get to the point.
Should point out that "whacking them in parallel" also only makes sense if the two current clamps have the same ratio (e.g., 1mA per A).
As per Kirchhoff’s laws, putting power output in parallel actually takes away from your house’s ability to produce power. You need to have the power sources be placed in sequence in order to get full power output (otherwise the power systems are trying to drive power the wrong way across each other).
I would simply put both cables in both clamps.
Yikes, that box is calling for a few terminal blocks, rails and daily beatings for the electrician who installed it; until morale improves.
There are some nice busbars for circuit breakers, it now makes more sense why they exist....
instead of giving each monitor seeing the sum of both productions, what about set each monitors consumption to house feed minus the others production. In parallel but one reversed. They now see their only production. consumption measured ( -3A out, + 2A )= -1, 2A production, 1A calculated consumption.
Makes sense to me!
That was what i originaly thought he was describing.
The software does not support that.
@@EEVblog the software does not have to support that. Software only has to support deducing own generation from total power. Power generation from outher solar system can be deduced in hardware using current transformer.
Maybe I misunderstand, but it's not in software? The clamp on the main feed in parallel with an inverted clamp of the other units output. The feed measurement would then be like if the other system wasn't there.
ref: 26:12
Has never seen a nest like that in Norway where I live. Even in houses build in the 60's they mounted meters and fuses on power-rails.
Same here in Finland, that’s an absolute disaster.
WOW... that fusebox is a real mess ! That cant be up to code ?
Passes code from the 1980's when it was installed, just that any additions have to be done to the code at installation, so that is why you still see the rewireable fuse in there, and the breakers and parts all running in any orientation.
Needs to be shut off, and the panel replaced with a 3 level enclosure, which will still fit the outer enclosure envelope, and then have a mains incoming breaker, and then the 3 rows can be dedicated to a particular function like house on top, solar in the middle and the bottom for monitoring and lightning protection. Will need a separate box though for the 3 electrical supply meter and ripple relays, and the incoming fuse, feeding the output through to the main breaker box in the cabinet, where a 3 pole isolator will control power coming from the grid. Also will allow the measuring to be done correctly, as you then have a common bus for each segment.
that is by far not the worst one i have seen, at least it all works and is up to some code standard.
@@SeanBZA I think the code in force at the time was sponsored by Fosters!
@@juststeve5542 Didn't say it is good,but it passed at time of installation, then successive generations of owners and electricians have done work as fast and as cheap as possible on it.
@@SeanBZA I'm not totally sure it's a requirement to upgrade here in UK (I'll check with my brother who is a a spark), but I know he would insist on upgrading that panel to modern specs if he was doing work on the property, otherwise he can't sign it off as being safe.
@@juststeve5542 Not a requirement, but there are some minimum standards it has to meet for sale, even if grandfathered in, there is currently here a need for all sockets to have RCD protection, which can result in you having fuse wire sockets with a RCD in the middle of it, and an accessible and marked disconnect, even if the board itself is in a cupboard or up high.
is this a legal powerboard? it looks like it will burn your house down every second now!
Very common in older houses in Oz unfortunately- they rarely had more than a meter and four fuses in them originally, and then over the decades have been butchered....
At "stop this video" I'm already tearing my hair out..figured it out as soon as you said two systems not aware of each other
I know, Dave can be very very long winded in his explanations, and repeating a lot of stuff.
based on my hunch and this reply i'll guess his meter(s) was(were) wrong. can't watch more than 1:44 on this subject, sorry.
@@VorpalGun right? And so like.. his tone if you didn't know better just sounds like he's so enthusiastic and like angry..but its hilarious
@@ivok9846 well its simply what said, the systems aren't aware of each other lol
@@forbiddenera there you go, the meters are off. he should make his own....hehe...eev(solar)blog meter.
If your wires had been long enough and the clamps wide enough you should have been able to drag the Enphase power through the reference clamp of your old system and the old system's power through the Enphase reference. This way and given the correct direction you should have been able to see the difference of the currents with single clamps.
Yes, unfortunately at the time of installation this was not thought of, so the leads were cut to length.
Why not have two current clamps on every solar system output. If you wire one of them to the production input of the data logger of the corresponding system and the other one to the load input of the other systems consumption input in parallel with the actual load measuring clamp but having the wires reversed for the clamp measuring the production of the other system (or just reversing the clamps install direction) you would subtract the generated power of the other system from the measured "load" and get the real remaining load.
EDIT: This is of course assuming that all current clamps have the same ratio, the output of the system is reasonably well synched to the grid (which it should be with the inverters tracking the grid frequency) and no massive amount of inductive or capacitive loads being downstream of the swichbox.
I have a feeling a breaker box like that would be highly illegal in Canada.
Nah just has to be on a farm, then you can ignore most regulations
@BASIL!!!!! The musical and pumpin' Seagull You also have the option of doing weed at the same time, so we got that going! They're charging people for playing golf or going to the park now, but weed shops are an essential service. God bless Canada.
@@redsquirrelftw > doing weed
Chrissake man are you 12?
@@redsquirrelftw And here in Ontario, our current panic lockdown has extended to prohibiting the stores that remain open from selling things designated as 'non-essential,' which appears to include clothing, furniture, housewares, hardware, and books and magazines. This is currently scheduled to last for a further two weeks, and has already been in place nearly a month.
@@evensgrey Yeah it's crazy here. Even masks are non essential LOL. I don't get it.
Installers should have known all of that and informed you and asked if you wanted the correction installed. Fail!
Yep!
Panels so powerful they give power to the sun.
Paralleling 2 current transformers in order for them to double the current is absolutely contingent on them having the same turns ratio. Ideally being the same make and model. Otherwise if one had 1000:1 turns and the other had only 100:1 then you be adding 10 times less current from the second transformer.
22:08 - Oh, boy! A spaghetti factory run wild! I retract my 'solution' below! ;)
So, any chance negative consumption could be called positive production...that might explain relation to the Sun activity?
That's exactly how I think too. More produced than needed.
ruclips.net/video/aO2xytlbGkA/видео.html
@@Manta_Dennis Words are funny that way, I am fairly sure he chise them carefully, did spoil the surprise, but it does not matter I suppose. Technical solution does...
The back of that panel looks like a right lash up no neatness no labels on the cables.
My system doesn't read the consumption, the power meter does that. SMA sells a meter for that, but my installer didn't bother, I guess it's not that popular in Germany. So for now I made my own scripts for monitoring (added to temperature/humidity monitoring in the house) to feed a Grafana server with the solar production. One of these days I swear I'll get to plug the optical transceiver for the energy meter to read those values, both power consumption/feeding and 24h/7d/365d values.
I guess if you had a system with equipment from the same manufacturer they could manage to get you something that does that out of the box. In my case, I can't be bothered with the SMA website other than checking the monthly trends and the web interface to the inverter is bad, so I made my own thing :-D
So the alternative is to find the API manual for the Enphase and Solar Analytics inverters, merge the data and read the consumption separately, and merge again.
We're nerds, aren't we? :-P
Wow that breaker box meets code anywhere on this planet? Scary looking rats nest! Is that made from peg board Dave?
One reason many of these old boards are still in place is that many are actually made from asbestos...- left alone, perfectly fine, but if you want to remove the backboard and replace it- major $$$ and a proper asbestos removal expert called in... So you just reuse whatever existing holes are handy to mount and run new breakers in (regardless of angles etc lol) because the alternative is likely to cost you a grand or more extra...
Why not putting 2 wires through the same CT Clamp - either then measuring both solar systems or sustracting the additional generation of the other PV System from the false grid current
Amazing how this entire house runs only a 1 Phase system.
Meanwhile in europe with 3 Phase systems in nearly all households, we would need 3 ct clamps for each contact point
That switchbox rats nest really bothers me. It hurts my electrical engineer eyes.
Or you could just whack the wires coming from both systems into the same current clamp and still use that spare clamp to measure your ACs.
Yup, that’s done in many substations where you have a single set of current transformers and multiple meters that need to measure stuff, just wire all the meter inputs in series with the CT and Robert is your mother’s brother. If I recall the same can be done with the voltage transformers, but I’d wager they’re connected in parallel. This of course assumes that both meters expects the same ratio transformers.
Yes, but the wired are already cut to length.
@@sstorholm I thought @TheMobilefidelity was saying to put both 240v feed wires through the same current transformer opening. So each clamp reads the current of multiple wires, as opposed to one clamp outputting to multiple meters as you are suggesting.
@@EEVblog "Cut to length." IMO it's best to leave wires as long as practicable, then you have extra length if your needs change. Here in the US you could also splice on another piece of wire as an extension, but I'm not sure if the Aussie regs allow that.
Looks perfectly fine for me. However, for Australians it looks upside down. Installer must have forgotten that he needs to change polarity because everything in Australia is upside down.
maybe try turn the solar panel upside down
@@DevideNull Good idea 👍
That way the electrons will go the other way!
Haven't seen 1080p50 for a while, what a throwback.
Totally followed the problem and solution, but what bothers me it what the panel wiring looks like. it looks like it was designed and constructed by a two year old, complete with a wooden back board. no wonder the toilets flush backwards.
Sweden dropped that style around mid 1950s. Then we had the ceramic fuses until late 80s and now we can wire in the meters anywhere because we use DIN. There is always a way if you are smart.
positive video. no negative feedback from me. I have lost all my remote settings for solar monitoring but not worried the unit is working well.
I personally would have done it differently. I would have installed the second current clamp from the first meter on the output of the second system, just reversed that the current is subtracted. That way each system would still be measuring only the power produced from that particular system.
There's a better solution: instead of adding the production of both systems and giving that to the production input for both systems you should add the production of the other system to the power from the grid.
So with Pa and Pb the production systems A and B and with G the grid input you should send
Pa to power input and G+Pb to house consumption for monitoring of A
And
Pb ... G+Pa... monitoring of B
Yout switchbox is a mess compared to ours (Netherlands)
To add to the confusion, both systems have peak production at different times of day due to roof angle.
That is one messy fuse box. What about busbars? DIN rails?
Great video on current topics delivered with a sunny disposition!
For the love of god can PLEASE somebody send him a german style fuse board??!!!1 He already uses all these breakers and stuff for the DIN-Rail but why do you have to keep putting them each in their own housing. My eyes are bleeding! Just get a german style fuseboard, big ones have over 100 slots for breakers and what not. (these slots are called "Teilungseinheiten (TE)" in Germany)
- Greetings from Germany 👍
Yep, it's a bit "DIY" isn't it. I.E. go buy a bit of board, poke some holes in it and mount your stuff on one side, and hope for the best at the back!
Dave, It is permissible to place two large opening size current clamp after the load breakers. It will read the sum of all the loads. This is easiest when all the loads exit the same side of the box, such as the bottom. Now both current transformers will read only the total load. Both sources will properly record the production of both, and show the system load, but will show the total system load even though there are 3 sources of power. Each system will show the total load, and each unit production. A buss bar from the main AC breaker to the load breakers is common. Instead of metering the AC utility, simply sum the individual loads through one CT.
My (simplistic perhaps) solution: Pre-join the arrays and have one measuring system measure the joint power production.
This is REALLY good stuff, thanks!
Instead of feeding the grid, how about installing your own energy storage... batteries of some sort? Is the net cost of consuming less from the grid lower than amortizing a battery investment?
You can run more than 1 wire through a current transformer. The sensed current will be the *sum of currents* in each wire, if the currents are all in-phase with each other. The sensed current will be the *difference of currents* in each wire, if the currents are 180 degrees out-of-phase with each other. So for single-phase systems you can add and subtract at will, to prevent the kind of errors discussed in this video, and usually correct them without need of any additional current transformer(s). Also you can increase the sensitivity of a given sensing range by puting the same wire through the current transformer more than once, in the same direction. For example, if the wire goes through 3 times, just divide the indicated current by 3 to get the true current. This technique is very useful for measuring very small currents.
As the unit has three inputs with a software change it could be made to measure both individually and combine them in software.
really surprised your breaker box wasn't updated when the solar was first installed that layout is awful
@EEVblog have you heard about or checked out the Iotawatt? Fantastic little open source device that gives you graphs like these but with two major differences: First it can monitor up to 14 separate circuits with a single device so you can monitor every single circuit in the house independently (with 5 second resolution logged too!), and two it avoids all the "cloud" infrastructure - your data is stored on the Iotawatt only. I've had mine for over a year and the detail is incredible
Excellently clear as mud. One man's negative is another man's positive (especially in electron flow) I still don't understand the basics of how excess power can be fed back the grid, but there must be a vid somewhere.
TBH, that was a bit disappointing. It was - at least for me - pretty obvious, what was going on here. Looking at the Solar Analytics graph, you can even see, that the 5kW installation kicks in later during the day, whereas the 3kW fades out earylier, just as you explained in the installation video.
14 Minutes later and the whiteboard stuff was actually wrong and corrected with this huge overlay ...
Not an EE, was expecting a swapped grounding contact erroneously adding up the voltages or something like that. Independently/double-counting the consumption just sounded too dumb on the end-user scale.
To sum it up, Aussie electric panels are a hot mess so it's hard for Dave to get good readings. Even without the pic of the panel, just the whiteboard drawing gets you to the concluding it's a mess.
Australia, One Phase? I am used to Two Phase with a 200Amp Main Breaker. And that is a breaker box? Rats nest.
Great place for when there is another plague of mice.
Sure your not thinking split phase? The US uses 240 volts single phase center tapped. So 240 single phase and 120 / 120 split phase from the center tapped transformer. Two out of phase 120's, but single phase 240.
@@jeffm2787 Yes, you are correct. Referenced from Neutral, I think of them as two-phase. I don't know if that is correct thinking or not. Just having a ground/neutral and 220vac would probably be easier. Plus is the relative current consumption roughly half at 220vac compared to 120vAC for most devices? I know it comes out in the wash. I just don't understand how he gets away with such little energy usage compared to here (at least with me and most that I know). I had to literally work my ass off to get down to about 750KWHs per month. Before last November, my average bill was $280 a month. It is now about $98 a month, but that was after switching to a purely hybrid how water heater and installing a 50 gallon well pressure tank (my 1.5hp pump is 350 feet deep!).
@@Daveyk021 240 volts in the US. People who live in the US that say 110 or 220 tend to show their age Then again once upon a time it was 230/115. Now 240 / 120 is the spec. My house right now is around 245 volts in 122-123 at the split. The price of electricity varies widely from place to place. I've had $650 / month bills and luckily now only see maybe $150 or so.
@@jeffm2787 Yea, I know it is 120vac ( I do certification work where I must vary a variac between 100vac and 140vac, and then settle back on 120vac - I still call 120vac: 110vac -loo). So, yea, I'm an old fart, $650 a month! wow; holly poop. I managed to get down to lower KWH usage even with my electronics shop running on the first floor 5 days per week, or so.
If what Dave was showing us was a "breaker Panel", it didn't look like he has many circuits in house and standards are really different. I have my tall 200 Amp Square D panel 100% full and that is only for the first floor. The second floor (house) has it's own 100 panel, full. When I did it down here, I just put too many separate circuits in (oh and I forgot, off the 200 Amp panel is a 60 AMP CGCI sub panel on the other side of the garage - lol). I probably have more copper wire run in this house than in all of Dave's neighborhood.
So this mainly seems like an Australian issue due to the outdoor box o wires. Here in the US unless the wiring was done between 1880 and 1940, you would generally have a meter base on the outside of the house and then have a service entrance panel in the basement or sometimes attic with common busbars for all the circuits in the house. If you install a transfer switch or have multiple buildings on the property you would often have an outside service distribution panel or transfer switch between the meter base and the service entrance panel in each building on the property. While you may have subpanels after the main service entrance panel, they are all fed from the service entrance panel upstream so it is very easy to either add in a Service distribution panel to connect the solar to or have it on its own small breaker panel and wired into a commoning bar in the transfer switch so the load in the house is on separate wires with enough room for separate current clamps on both the load side and the solar generation side.
19:16 that so cool you can see each panel and the low ones are shaded
17:51 if you parallel them up you won't be able to know what each array is making on their own
Yes I do. The Enphase tracks it's own production and I can simply subtract that from the total production to get what the old system produces.
Even if it doesn't measure it's own production can't you set it up with only 1 system in parallel to measure total production and other only measureing it self and then do calculations for there to split it per system
(Though system not hooked up in parallel would have the wrong total number as before)
can you hook an oscilloscope or spectrum analyzer to the panel? those micro inverters are dreaded amongst amateur radio operators as many of them cause terrible interference
GAAAAAAAAHHHHHHHH! oh my god, if I ever left a panel looking like that I'd be fired on the spot, also if uh no WHEN you have an electrical fire I'll know why.
When I go on service calls for intermittent or circuits not working I seriously question my choice of profession when I open a panel like that.
The fix of combining the 2 monitors in parallel means that you can no longer track how each set of panels is performing. If you can export the data from each system it would be simple to make a spreadsheet that would combine the data from both and get you the house consumption data you want. Add the generation numbers from both systems together and subtract the power sent to the grid from one system (both should be reporting the same current going out), that should give you the current draw of the house. Other way would be to take the positive generation value from one system and add it to the negative value of the other system, the difference there should be the current draw of the house.
Thank you for this video
As of 6:50, thinking about this...two solar systems, with monitoring systems that don't know about each other, and both say solar consumption drops when the solar production goes up.
Because the two monitoring systems don't know about each other, all they know is how much power is produced by the system each monitors and which way the power goes (into the grid or into the house). When total power provided from both systems exceeds household consumption, each monitoring system sees only that the power from the solar system it monitors isn't being fully used in the home and records that. To eliminate this monitoring anomaly, you need either one monitoring system for both solar arrays, or a means to cross-connect the monitoring systems so that they both know about production and consumption from the other array as well.
Another solution would be to run the AC wire from the opposite system through each grid side current clamp. Any current from the opposite system would be going through the current clamp in both directions on it's way to the grid, thus cancelling itself.
Emon pi open source energy monitor has logic to combat this. It's a perfect solution. I have a similar logical set up as yours and I can determine all energy components using only two CT's
Both current transformers should have same ratios to parallel them.
Kirchhoff’s laws force you to put everything in sequence in order to avoid power sources interfering with each other and forcing current backwards against the other source.
not a panel board or din rail system, but a real panel board....... wow. learn something new every day.
Apparently, electrical wiring standards are sure different between countries! It seems a lot simpler with a single 240 V phase. US 240 V split-phase panels are much more organized and modular. In Japan, modern 200 V split-phase panels are also organized and modular, but they don't really involve the concept of a safety ground. Most wiring is two wires only. Thanks for showing your electric service panel, I learned something, in addition to the subject of solar power monitoring.
If you can fit both of the conductors that you want to monitor through the same CT clamp jaws, that the easiest and most accurate way for a summed measurement. You can indeed parallel CT's when well matched (same number of turns and specs), but you only need to do these things if the measurements are physically somewhat far apart or can't fit multiple conductors in the CT. There are also instances where placing the CT's in series is a better option, if burden is affecting the measurement accuracy.
if you add the export from the new system to the consumtion you will get positive values... depends where you measure your consumption...
It's hard to get the clamps wrong, my first thought would be that the panels are from two sets. I like that you can see the panels separated. It's a first in first out problem.
Yeah that fuse panel is one heck of a rats nest. You should replace it next opportunity. In the UK we use a common neutral DIN rail mount neat & tidy. Get a battery soon as you can - way better than pushing back into the grid. Just not Tesla. Many people build their own 18650 battery system. Also if you still want to keep an eye on your aircon, Shelly make a wifi transformer meter shellystore.co.uk/product/shelly-em-50a
So, the 2 systems are fighting each other. Could have told you that up front.
I'm shocked what you call a fuse box. it's a rats nest. Aren't there any electrical standards in Australia like in the rest of the world where you have standardized breakers on power rails???
Couldn’t you use the parallel transformer trick to subtract production A from the consumption reading made by monitoring system B? Rather than combining production readings?
Would a good solution be to put a small box upstream of the whole house which is fed from the grid and feeds the original house box? That gives you a clean place to put the solar connections and a clean place to put the clamps for monitoring house consumption.
If you put the third clamp intentionally backwards, and wired it in series instead of parallel with the second clamp, would it end up canceling out the current of the opposite inverter? I can see where that would be beneficial to see only the current produced by each inverter.
They should have an offset output/input so you run a wire from 1 box to the other, so it can say "this is what I am putting out" and then the other box can calculate the difference. That way you could chain them as well because each system would be subtracting the offset of the ones wired before it.
You don't even need parallel transformers!
For the 3kw system, on the consumption sensor, run the 5kw source wire BACKWARDS through it. It will sense the forward current, and then the negative of the same current to zero it out. Repeat for the 5kw consumption sensor and the 3kw source wire!
And what if join two clamp meters on the consuption side? One on the old place and one on the second solar system OUT. Production will be mesured separate for each system, and consumption will be "electricly" calculated like Dave has explaind.
I'm more than slightly horrified that your power panel is nothing more than a masonite board. That is actually a legal power panel in Australia? How does your property not burn down? You have 8kW of PV and that would require an 80 amp breaker here in California and you might not even have an 80 amp service into the property?
What if you run two wires through the current clamps? Like, run the input current through positive-wise and then run the generated current from the *other* solar panel backwards through the current clamp. You would be left with the difference.
One set of panels were installed upside down and the electrons were falling out.
Or add a CT on each load breaker, then parallel them for total consumption? Then keep one on the mains input for net metering?
Instead of paralleling the currently clamps, couldn't you connect the Enphase current clamp to channel 3 of the Solar Analytics? That way you could still see production of both systems instead of the aggregate production of both systems.
Is that a Faber-Castell TR1 Calculator/Slide Rule?
You should do a video on that.
Great Channel by the way.
Well, those switching boards are a mess. Used to see and work in European din rail mounted switch boards
Could you connect the second ct from system 2 inverted in parallel with grid ct for system 1. And the same for system 2
Or put the wire from system 2 reverse parallel with the grid cable in a single CT. So that de current from system 2 is canceled iutt
Can't you just put a second current transformer in parallel with the load sensor, but reversed on purpose, on the solar output of the respective other system? That would subtract its output from the total going to/coming from the grid.
Btw. I'd claim that a switch box looking like that will get an electrician fired on the same day here in Austria (not Australia). As if you hadn't enough fires already.
7:12
Do we do anything to prevent current flowing into the solar setup from the grid?
Sorry if that's a stupid question!
The inverter is in-between the grid and the panels. No current would flow into the panels. Grid is AC, panels are DC
@@ionstorm66 Thanks man
At night here in England, with no production, my Enphase system draws about 1A quiescent current. I presume this is to keep the micro inverters alive for the sunrise next morning. I validated this by turning the isolator to the Enphase system on and off at the grid connection switch in the fuseboard. When the sun comes up and production starts the current goes the other way up to around 15 Amps. (My grid supply is 240V AC @ 50 Hz single phase). fyi I have 3.7 kW installed, 16 panels & microinverters 7 years old. Faultless system, one of the best things I ever bought! Good support to my Nerd questions by Enphase tech staff. I feel the staff like what they do .
I would have thought that the analytic systems had a comms line to talk to other systems, I guess compatibility comes into play.
The current transducers in parallel is a good fix however.
By the way, a transformer is a power transmission device whereas transducer is a signal transmission device.
With my Fronius Smart Meter, it's between the input and the output, it has 2 inputs and 1 output, 1 input is from the inverter, the other input is from the street, all the circuits have no choice but to go through that smart meter, which allows me to monitor the street power being imported, the power being exported, the power being generated, and the power being used by all the connected devices in the house.
But my house was also built in 2014, and Western Power tends to be a bit more anal about certain things :P
but you could to measure the tow systems independently let the current flow thru the second parallel coil backwards and subtract the current that is produced by the other system when you put it in parallel with the Grid coil ??? or is there a fault in my thinking ? would maybe not be the most accurate system^^
Owwww!!!! I didn't get this when I saw that tweet, but I realized it almost immediately at start of this video.
That panel..... brrrrr..... :-) It works and so on but MAN! that looks sketchy.
What if you parallel the existing current clamp used by one system to measure the consumption with another clamp that measures the production of the other system but installed backwards. Like this it should read be the difference between the total current pushed to the grid and the one produced by the other system. Would that work?
18:50 Was it not possible by inverting the parallel connection of the input and the respective other generation (measure twice per generator) to subtract the respective other generation from the network measurement in the measurement?
So would you subtract the number of turns by half in the current transformers in series?