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No AC loads yet Quattro reports a 244W AC draw while charging?? Pic attached.

NorthTown2022

NorthTown2022

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Northern Ontario
I am currently commissioning a Quattro 48/5000/70 single phase unit and a 280ah home made battery before moving everything to a cabin in the woods.

The only thing hooked into the L1 out are three recepticals with NO load and a lightning arrestor (which was removed for testing purposes).

The draw only appears while charging battery with temporary AC power I have wired in from my main service panel.

There is no PV hooked up yet.

Any thoughts on this?

@John Frum
@sunshine_eggo
 

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244 watts is ~9% of 2682 watts.
Is the charger within the inverter/charger showing up as an ac load?
To test this change the charge current to a lower number and the ac load should be ~9% of new lower generator figure.

This would be cool because it would mean the charger in the Quattro is very efficient.
I would have been happy with 80%.

Dont make the charge current too much lower though as the charger's efficiency curve is likely not flat.
 
I've never seen this, but I've never AC charged at more than ~1700W (15A/leg generator output limit). At the time, I did have loads, but the loads seems typical of what I expected at the time.

Recommend posting over on Victron community's site.
 
John Frum said:
244 watts is ~9% of 2682 watts.
Is the charger within the inverter/charger showing up as an ac load?
To test this change the charge current to a lower number and the ac load should be ~9% of new lower generator figure.

This would be cool because it would mean the charger in the Quattro is very efficient.
I would have been happy with 80%.

Dont make the charge current too much lower though as the charger's efficiency curve is likely not flat.
Click to expand...

I'm skeptical of my own hypothesis.
2682 ac watts in
2133 dc watts into battery
2682 - 2133 = 549 watts
That gives 80% efficiency and doesn't tally.
 
John Frum said:
I'm skeptical of my own hypothesis.
2682 ac watts in
2133 dc watts into battery
2682 - 2133 = 549 watts
That gives 80% efficiency and doesn't tally.
Click to expand...

Of course watts are subject to losses and amps are not.
 
Last edited:
@sunshine_eggo what is your best guess for Quattro charger efficiency.

I believe the Quattro is in charger only mode for that screen cap.

I bet that is not a use case that gets huge test coverage.
 
Last edited:
So the numbers are all proportionate
80% overall efficiency and the ac load is close to 9%
I guess that means there is ~10% of the charger wattage is lost to heat before the shunt.
That is assuming the charging data is provided by the shunt.
I guess there could be calibration errors as well.
 
I may be totally out to lunch on the math today and I still don't buy my own hypothesis.
 
Since its proportionate to the charge current I'm not too worried about its effect on battery commissioning.
 
John Frum said:
@sunshine_eggo what is your best guess for Quattro charger efficiency.
Click to expand...

85% peak

NorthTown2022 said:
Charging at 15
Click to expand...

15 * 120V = 1800W. Seems like you're shy on charger output.

Do you have "Weak AC Input" enabled on charger in VE config?

NorthTown2022 said:
Charger only
Click to expand...

Hmmm... I can only guess that it's making up for what's left over. VRM can be configured as having a DC system, but it's just a catch-all. Whatever it can't account for, it dumps into the DC load bucket. I wonder if that's what it's doing in charger mode... anything not accounted for in AC-in and charging gets dumped out as an AC load.

Did you try inverter mode?
 
I'm guessing the inverter/charger can't be calibrated.
Can/should the shunt be calibrated to the inverter/charger bulk charge current?
Then calibrate the voltage to the inverter/charger float voltage?
 
Hmmm... just putting the numbers there for my own reference...

244W / 2133W charging = .11439
86W / 751W charging = .114514

2133W charging / 2682W input = .7953
751W charging / 930W input = .8075

I need to test this on my own system with the generator next time I'm up there. I've always had AC loads to some degree while charging, but I've never charged at more than about 1700W. Assuming the same relationship, I think I'd have noticed an extra 150-160W...
 
In retrospect, I don't have to... I can just go back through VRM and see when I did it last... This is the only time I can find where I actually charged with the genny in the last 6 months:

1660057961132.png

Blue line is generator, red line is AC consumption, orange is battery current (shunt). My solar was offline at this time.

When generator comes on, I see no corresponding increase in AC consumption.
 
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