Can't charge up from solar panels

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NoInverter

Member
Joined
Apr 23, 2016
Messages
5
My dream of charging up the i3 from the solar panels has been dashed. Here's the problem: Most inverters though labeled sine wave inverters do not produce a wave form close enough to the one produced by the utility companies. I have Xantrex inverters SW 4048 purchased in 2006. So the charge panel on the cable provided by BMW for 120 volts reads "power fault. My inverters run everything in the house-tvs, microwave ovens, electronic gear and so forth. Why is it necessary that the car have that perfect of sine waves?
Think about how simple it is to charge up a battery with a charger bought at WalMart. When I bought the car I told the sales Person that I intended to charge up from a solar panel setup. Does not denying that constitute misrepresentation. Somewhere in the BMWi3 hoopla was a section labeled Green Energy or similar. There it talked about charging up from solar panels.
 
Not sure what your problem is, I can charge from our panels no problem (ET Solar panels SMA TriPower inverter) Anytime the sun shines, we export to the grid, the inverter syncs to the grid so I think it has to match the frequency and boost the voltage slightly to make the current flow. The i3 charges from the solar or the grid no problem. Included EVSE or our Juicebox 40 both work from the solar.

Are you grid connected?
 
Not connected to the grid. And that is a big difference. I suspect that you export power to the grid when the sun is shining, but are always using grid power. Do you have batteries?
 
No batteries.

Sounds like you need to have grid spec power to charge the i3 even if you are not connected to the grid.

We only use grid power when the sun isn't shining. 10kW of panels. Nett metering. Any solar power used on the property doesn't go via the grid.

The issue is that our inverter syncs to grid spec power when we have exportable power. Yours doesn't, and the built-in spec in your inverter doesn't seem to be grid compatible and the i3 doesn't like it.

Might be worth talking to your inverter supplier. Maybe they can tune up the inverter.
 
the evse is just a power switch that advertises what the current capabilities are to the car and a really fast on/off switch. If the evse is reporting the error and not the car, it's most likely ground fault where the ground fault protection thinks ground isn't there or not wired properly. the supplied charger is extremely sensitive to ground fault, I got a different evse and never had a problem since.
 
While somewhat expensive, you might consider a true sine-wave UPS in between your inverter and the EVSE feeding the car. The inexpensive ones would likely have the same issue...a stepped sine-wave approximation verses a real sine-wave. FWIW, a stepped sine-wave to a big power supply can often look like almost dcv, and overheat the rectifiers. My guess, the EVSE does not see the acv as clean enough, and won't turn on. The EVSE has it's own logic board and needs to make local power to run its electronics and provide the signal lines to the vehicle...those need to be 'normal' line voltage signals, not approximations. Some electronic devices just don't like dirty line power. You might be shortening the life of things in your home, and not realize it as well.
 
Hi there. Just like I33t, we are also able to charge from our panels, but our maximum generation so far has been just over 3kW, so in order to use PV electricity only, I have to use the 3 pin charger and lower down charging rates in the car settings. Also, our car isn't always at home when the sun shines, which is probably the biggest fly in the ointment.

I'm already looking into storage systems and will probably add one to our PV system when the price is right. But even then the actual delivery rate of the storage system is key, as you need to be able to charge your car within a reasonable time. Some systems offer 3kW, while a Bosch system promises up to 5kW delivery.
 
Thanks to everyone who took time to respond to my problem. The inverter Xantrrex SW 4048 is advertised as a sine wave inverter. It cost $3000 when new in 2006. Like I said it operates all the household appliances without problem. The plug which I used was grounded. The whole system cost about $50,000.
I agree that the EVSE doesn't like the electricity its getting. But I think its a bit too fussy. Interestingly there has been no response from BMW. Perhaps if a circuit diagram or description of the tests on the incoming current were made available, a solution could be created.
I also have DC available at 12,24,36,and 48 volts. :( :(
 
Best to find other i3 owners nearby and find one with a non-BMW EVSE to try.

It might just be that the standard EVSE is too finicky.
 
To use DC on the i3, you'd need LOTS more voltage than you have, and add the logic to make the car happy while communicating back and forth to adjust the voltage and current levels.

While annoying, if the supplied EVSE works on commercial line voltage and doesn't on yours, that implies that it isn't a true sinewave. Only way to verify that would be with a good scope and maybe a spectrum analyzer to look for harmonics and distortion. The frequency may or may not be stable, either.

You might check for any voltage between neutral and ground in the receptacle...then, the voltage between hot and neutral, then hot and ground. If you only get a voltage reading of your nominal level between hot-neutral, and hot-ground is either zero or fluctuating all over the place, you don't have a good ground there. Depending on the meter you use, unless it is a true sinewave, it may not read correctly.
 
So here's another question.

Does your inverter have a true sine wave or does it have a modified sine wave output?

modified-sine-wave1.gif


Put a scope on it and you will find out.
 
Perhaps this will help someone out there. In the end, I found out that for some reason the charger will not work on a GFCI circuit. A freindly guy with knowledge from Clipper Creek who works on the charging systems said to avoid GFCI circuits. So in the end it had nothing to do with on or off grid or solar or anything except BMW's failure to tell the peons about this problem.
 
FWIW, an EVSE (at least those sold in the US) effectively have a GFCI like circuit in them. While it SHOULD work when connected to an external one, apparently it doesn't. Because of the switching of anything other than a true since wave, each step creates some harmonics. Some things can work with them, some can't. Harmonics can cause the current flow to be a little erratic and look like a fault. Those do not aid the long-term health of electronic circuits unless they have a robust inlet filter and voltage regulation circuit.
 
If it is a GFCI problem, then I'd have your electrician bring a range of different brands and types of GFCI circuit breakers.

Get the sparky to check the circuit is in good condition and has no minor ground fault before the charger is connected. If that circuit is fine, then try replacing the GFCI circuit breaker.

Our 40A wall charger is on a ground fault circuit and it has never tripped. The occasional use charger has also never tripped. We have plenty of solar panels and no problem.
 
I have only tried my outside, GFCI-protected receptacle once with my OUC, just to verify it worked. No problem.

One thing to note, at least in the USA, it is okay (not preferable, but better than nothing) to have a GFCI without a ground wire. This is often used in older structures where they only have hot/neutral (i.e., a 2-wire power cable) and allows you to plug a 3-prong plug into it, get the GFCI protection, but not have the extra safety ground wire connection (ideal). Your EVSE will NOT work on one of those...it needs a real ground. It could be as simple as a loose or missing ground wire.

How fussy the i3 is about incoming power, I don't know, but a real, actual (not simulated) sinewave works best with it, and the EVSE won't condition the power, it only passes it through (except for whatever it needs for its internal logic).
 
NoInverter said:
My dream of charging up the i3 from the solar panels , led solutions has been dashed. Here's the problem: Most inverters though labeled sine wave inverters do not produce a wave form close enough to the one produced by the utility companies. I have Xantrex inverters SW 4048 purchased in 2006. So the charge panel on the cable provided by BMW for 120 volts reads "power fault. My inverters run everything in the house-tvs, microwave ovens, electronic gear and so forth. Why is it necessary that the car have that perfect of sine waves?
Think about how simple it is to charge up a battery with a charger bought at WalMart. When I bought the car I told the sales Person that I intended to charge up from a solar panel setup. Does not denying that constitute misrepresentation. Somewhere in the BMWi3 hoopla was a section labeled Green Energy or similar. There it talked about charging up from solar panels.
Click to expand...

Hello,
My experience will help you out , charging via the provided EVSE is that it can be a bit 'hit and miss' when it comes to starting the charge. If the start fails then I find that I have to disconnect the EVSE from the car and go through the start up process again. To my knowledge, there is no way of turning off the charge from the APP. Other EV users have reported using a wifi-controlled socket but bear in mind that this is another set of pins which could result in arcing.
 
jhu321 said:
the evse is just a power switch that advertises what the current capabilities are to the car and a really fast on/off switch. If the evse is reporting the error and not the car, it's most likely ground fault where the ground fault protection thinks ground isn't there or not wired properly. the supplied charger is extremely sensitive to ground fault, I got a different evse and never had a problem since.
Click to expand...

Ya.
EVSE is just a safety extension cord. It does not power sample for quality.
Just try another EVSE. Likely some other issue ( ground , voltage etc )
 
There is a power supply in all EVSE devices that generates power to the internal interlock and control signals it uses to communicate with the car, i.e., a logic board that runs off of low-voltage DC. But, the power it passes through is just line voltage that the car then converts to the high voltage DC to recharge its batteries.
 
NoInverter said:
My dream of charging up the i3 from the solar panels has been dashed. Here's the problem: Most inverters though labeled sine wave inverters do not produce a wave form close enough to the one produced by the utility companies. I have Xantrex inverters SW 4048 purchased in 2006. So the charge panel on the cable provided by BMW for 120 volts reads "power fault. My inverters run everything in the house-tvs, microwave ovens, electronic gear and so forth. Why is it necessary that the car have that perfect of sine waves?
Think about how simple it is to charge up a battery with a charger bought at WalMart. When I bought the car I told the sales Person that I intended to charge up from a solar panel setup. Does not denying that constitute misrepresentation. Somewhere in the BMWi3 hoopla was a section labeled Green Energy or similar. There it talked about charging up from solar panels.
Click to expand...

hi I think its your inverter that is sine wave sure, but has a built in safety ground fault in the circuit of the inverter so that if you become the circuit interrupt to ground it shorts out to provide safety so you don't get electrocuted or something like that. so the 110 would be live wire 1 and neutral the return path through neutral will be unbalanced so the ground fault triggers.

that is why on my pure sine Aimes 8kw inverter L + N and L2 + N, or L1 + L2 for pure 240 VAC but not 3 wire L1 + N + L2 like a 3 wire drier wire would be.

L1 + L2 for pure 240 VAC have charged BMW i3 hooking up inverter to 20 Amp 240 VAC Level 2 Charger. It works for me anyways.
 
After all it wasn't the solar panels or the inverter that was the problem. A nice man from Clipper Creek (they make the charger cables) He said they don't work on GFI protected circuits. So I used an inside plug in the house and no problem. Most US houses have GFI protected circuits in wet locations, including outside plugs. The real question to me is why BMW didn't share this information with me. In spite of the fact that they have their so-calledgeniuses response for help and instructional materal are lacking
 

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