question

jleroux avatar image
jleroux asked

Generator not charging batteries

I have a 5kVA Quattro, running ESS. AC1 in is Grid, AC2 in is Generator.


My challenge is that in the event of a grid failure and if my batteries are low and my generator is running, it does not charge my batteries (or shall I rather say it limits current drawn from the generator to around 8A). AC is synced. Current limit on AC2 is set to 15A.


If I do increase required output power, it draws the additional power from the generator until it reaches the 15A mark. So my issue is the fact that it does not use available generator power to charge my batteries.


This use to work. No idea why it stopped

Generator
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Alexandra avatar image Alexandra ♦ commented ·

@jleroux

If nothing has changed, as in you have not updated firmware or changed any programming, then it may be good to check the generator itself. Drawing the 15A on loads test was a good start, but that does not mean it is running well.

The next thing to check would be your batteries.

Since you do not mention what type of battery you have it may also be these are not well? How do they charge on grid or solar?

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jleroux avatar image jleroux Alexandra ♦ commented ·

HI @Alexandra, I have 4x Pylontech 2.4Kwh batteries. They charge from both grid and Solar - So MPPT installed

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Alexandra avatar image Alexandra ♦ jleroux commented ·

@jleroux

I think JohnC's answer may also apply. Also Pylontech have a gentle charge as well. If DVCC is enabled it could be the batteries dictating that charge rate.

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jleroux avatar image jleroux Alexandra ♦ commented ·

@Alexandra, I hear your point about Pylontech, but as soon as AC is restored, batteries charge at very high rate. Can't remember exactly but close to 60A I will say.

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Alexandra avatar image Alexandra ♦ jleroux commented ·

@jleroux

It's a strange one then. Especially if nothing has changed on your system other than time and use.

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jleroux avatar image jleroux Alexandra ♦ commented ·

@Alexandra I will probably try a firmware upgrade and see if that helps

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jleroux avatar image jleroux jleroux commented ·

@Alexandra, just an update on this. I did a firmware upgrade, and still the same results. I have set Gen input to 20A. This picture tells the story

1605767838604.png

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1605767838604.png (641.4 KiB)
jleroux avatar image jleroux jleroux commented ·

And this is when all is connected and back on:

1605767954008.png

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1605767954008.png (144.4 KiB)
Alexandra avatar image Alexandra ♦ jleroux commented ·

@jleroux

Looks like it is only using pv to charge the batteries and then generator to run loads. Maybe ESS causing this? Not sure.

Have you told the system to keep batteries charged when on the generator?

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jleroux avatar image jleroux Alexandra ♦ commented ·

@Alexandra


Yes I have. Have set it to: Keep batteries charged

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jleroux avatar image jleroux Alexandra ♦ commented ·

But if you do look at the screenshot. There is a small charge (very small) from the inverter going to the batteries.

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Alexandra avatar image Alexandra ♦ jleroux commented ·

@jleroux

It is possible that the generator is not putting out a good sine wave.

Maybe over time is has deteriorated, which is why it was fine before but not so much now.


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jleroux avatar image jleroux Alexandra ♦ commented ·

@Alexandra

I don't think so. Generator isn't used a lot, and it is a Honda with a Digital AVR in

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1 Answer
JohnC avatar image
JohnC answered ·

Hi @jleroux

I experience exactly the same thing with a 5kVA Multi, right down to the figures you quote.

I attribute it to having 'Weak AC' selected in the Multi, which I must do for genny acceptance. So I can't test that either way. No ESS in my case, just pure offgrid, and I see it often in winter.

The literature warns of this, but doesn't actually say that it applies only/largely to the charger. But passthrough doesn't seem to be affected by the 'modified' power.

This is just my theory of course, and if it turns out to be something else I'd be interested in knowing too..

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