Use of Portable Generator to Charge the Battery in an Emergency

[IssacZachary]

Yes, basically. It's JUST electricity, electrical energy.

John Kuthe...

I've only seen where pure sine wave inverter generators work (after the grounding issue is resolved). With construction type generators this is the only test that I know of and it didn't work:

A "pure" sine wave? How does whatever knows the difference won't work if it's NOT a "pure" sine wave? And what's the metric and allowable level of impurities from a "pure" sine wave?

John Kuthe...

I don't know. All I know is that there seems to be a lot of pessimism that it won't work, and the few tests that have been done seem to confirm this.

Maybe the Leaf's charger ramps up faster than a normal generator can and that for some reason stops the charging process immediately. I really don't know why it doesn't work.

But the day I see someone on here go get a construction grade generator and charge their Leaf off of it just fine I'd be getting one myself right away. But until then I'm keeping my eyes out for a good used pure sine wave generator.

[BrockWI]

I believe the stock EVSE has a pretty tight range for allowable variances, just guessing here, but maybe 59 to 61 hz and 115 to 125 vac? Maybe someone has already found the range?

It amazes me that when the car starts charging it is a sudden "hit", it could so easily ramp up the draw and then most gensets wouldn't have a problem, but when you drop an inductive load of 1300 watts all at once, all but the largest gensets will bog a bit, thus dropping out of range for a split second on the EVSE.

With the stock EVSE I personally have used a Hondau EU2000i and it works fine, once charging you can switch in to "eco" mode to slow the genset a bit, but you can't be in eco mode to start. I have also used the stock EVSE with a xantrex prowatt 2000 and it works from that as well. I have tried a "well used" generic 2500w genset and the EVSE would just never start, kept going in to fault when it tried to start charging.

[IssacZachary]

With the stock EVSE I personally have used a Hondau EU2000i and it works fine, once charging you can switch in to "eco" mode to slow the genset a bit, but you can't be in eco mode to start. I have also used the stock EVSE with a xantrex prowatt 2000 and it works from that as well. I have tried a "well used" generic 2500w genset and the EVSE would just never start, kept going in to fault when it tried to start charging.

That sounds typical. Both the Honda EU2000i and the Xantrex Prowatt are high quality true/pure sine wave inverters. Frequency, voltage and wave form won't hardly change on those (unless it's in eco mode). And the wave form is not a modified sine wave on either.

Personally I've been contemplating either getting a Honda or Yamaha sine wave inverter generator or install a stand alone sine wave inverter and then running a 12, 24 or 48V DC generator.

The latter option would allow me to expand to using solar energy to charge the Leaf some time in the future. It would also allow me to possibly build a larger +6kW generator that would be lighter for a small hitch basket (perhaps as light as 100lbs vs +200lbs for a 240V inverter generator set.) since the weight of the inverter would be placed somewhere on the Leaf itself. Also if I didn't go that powerful I could make it run off of a 12V system and then charge my Leaf off of another ICE car in an emergency.

[rmay635703]

Cheap generators are nothing but pure sign wave
Where they fail is in unsteady HZ and startup voltage.

Cheap inverters are not pure sign wave.

[LeftieBiker]

Cheap generators are nothing but pure sign wave
Where they fail is in unsteady HZ and startup voltage.

Cheap inverters are not pure sign wave.

Interesting. I'm guessing that the pure sine wave is because they use rotating coil/stator setups? I've been reluctant to use electronics with my Champion (Honda) clone, but it's never caused a problem when I have.

[IssacZachary]

Cheap generators are nothing but pure sign wave
Where they fail is in unsteady HZ and startup voltage.

Cheap inverters are not pure sign wave.

True. Don't cheap/construction grade generators also have voltage spikes when loads are dropped?

[JGR]

I ordered this DuroMax 5500EH to charge my Leaf in case I got stranded when going on a adventurous trip that might take me somewhere there is not a charging station in range. I used it with my OpenEVSE it worked without being grounded or a special plug modification. I started out at 6A and gradually increased the load to a max of 14A and it ran for about 20 min. then suddenly quit charging. I had tried 16A and the generator surged and bogged down enough for the OpenEVSE to error out. Looks like max current should not be over 12A and probably 10A may be the max for longer charge period. I need to now find out what I damaged, the breaker did not trip. I haven't checked it out today yet to see what the problem is.

https://www.dropbox.com/s/mrfbn92w9g2lu ... 6.mp4?dl=0

[JGR]

Good News!! The DuroMax Lives!!. Must have been a thermal switch situation, as it now is charging quite happily at 12A. I ran it for approx. 30 min. no issues.

Here is a link to a video when I was running at 14A which caused it to suddenly quit charging after about 20 min.

https://www.dropbox.com/s/mrfbn92w9g2lu ... 6.mp4?dl=0

[VancleVector]

To get the most “bang for your buck” try your best to achieve the 10% of the bank’s AH rating. Obviously there will be times when this is not possible such as having too small of a generator or too small of a charger. You can charge at a lower current, it just won’t be as efficient.

If you charge with more than 10% of C20, you risk damaging the batteries due to over heating and over gassing.

Let’s try another example:

This time we have sixteen Trojan T105s (225 AH @ 6 volts) wired in series and parallel to make a 48 volt battery bank. There are two banks of eight batteries that are paralleled to make 450 amp hours (C20) at 48 volts.

[GlennD]

The Harbor Freight 3500W unit was a waste of money. It does not recover fast enough and cycles over and over. My 120V inverter 2K unit works fine. I did have to connect the neutral and ground together in a shorting plug. Since it is used alone this is OK. Tied to a panel this is poor practice.