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Sol-ark 12K - odd behavior charging from generator

Llaves

New Member
Joined
Dec 27, 2021
Messages
204
Location
Llaves, NM
(Off-grid system, generator on Grid breaker)
On Tuesday my batteries finally dropped to 25% SoC (first time July installation), triggering a generator charge cycle. Here's what the usage looked like:
1674252137063.png

(the lower charge rate in the fourth "period" of the charging is due to dropping the Charge A setting from 150A to 130A at the suggestion of tech support who thought I might be over-loading the generator. Possible, but doubtful. It's a 14kW generator, and even after derating for altitude and fuel (nat. gas vs. propane), should still be good for 10kW.)

After about an hour, the grid would drop to zero, as would the charging. A few minutes later the charging resumes. Sol-Ark points the finger at the generator, but when I had a chance to check the generator's event log (ie, on the generator controller, not the Sol-Ark), it showed a start at about 8AM and shutdown at 12PM, with no events in between. My experience in the past with other Kohler standby-class generators is that when a generator experiences an out-of-range condition (over-current, unstable voltage, etc) it shuts down, records the event, and locks out until manually reset. The generator has no internal means of cutting off power to the Sol-Ark other than the circuit breaker so it has no means for dropping the load and continuing to run, let alone restart the load.

I suppose in theory the BMS for the batteries could switch off, say for temperature, but it seems unlikely this would occur at the same time for all four batteries. And presumably the Sol-Ark would record some sort of "lost DC" error.

The DC side of the Sol-Ark is getting downright toasty during charging -
1674252842444.png

which leads me to wonder if the Sol-Ark shut down charging for a few minutes because of high temperature. This doesn't seem right either, though, since the temperature continues to increase during the charging cycle, with the temperature at the end higher than anything up to the first or second load drop.

One other possibility is that this is just a phantom phenomenon, just an artifact of the sampling and plotting and that nothing is really happening.

So, anyone else seen anything like this?
 
(Off-grid system, generator on Grid breaker)
On Tuesday my batteries finally dropped to 25% SoC (first time July installation), triggering a generator charge cycle. Here's what the usage looked like:
View attachment 130690

(the lower charge rate in the fourth "period" of the charging is due to dropping the Charge A setting from 150A to 130A at the suggestion of tech support who thought I might be over-loading the generator. Possible, but doubtful. It's a 14kW generator, and even after derating for altitude and fuel (nat. gas vs. propane), should still be good for 10kW.)

After about an hour, the grid would drop to zero, as would the charging. A few minutes later the charging resumes. Sol-Ark points the finger at the generator, but when I had a chance to check the generator's event log (ie, on the generator controller, not the Sol-Ark), it showed a start at about 8AM and shutdown at 12PM, with no events in between. My experience in the past with other Kohler standby-class generators is that when a generator experiences an out-of-range condition (over-current, unstable voltage, etc) it shuts down, records the event, and locks out until manually reset. The generator has no internal means of cutting off power to the Sol-Ark other than the circuit breaker so it has no means for dropping the load and continuing to run, let alone restart the load.

I suppose in theory the BMS for the batteries could switch off, say for temperature, but it seems unlikely this would occur at the same time for all four batteries. And presumably the Sol-Ark would record some sort of "lost DC" error.

The DC side of the Sol-Ark is getting downright toasty during charging -
View attachment 130694

which leads me to wonder if the Sol-Ark shut down charging for a few minutes because of high temperature. This doesn't seem right either, though, since the temperature continues to increase during the charging cycle, with the temperature at the end higher than anything up to the first or second load drop.

One other possibility is that this is just a phantom phenomenon, just an artifact of the sampling and plotting and that nothing is really happening.

So, anyone else seen anything like this?
You could attach a digital multi-meter to inverter and use the meter's min/max function after the generator starts. This should give you the high and low voltage reading while the generator is running. Then you'll know if it's the gen or the inverter.

 
You could attach a digital multi-meter to inverter and use the meter's min/max function after the generator starts. This should give you the high and low voltage reading while the generator is running. Then you'll know if it's the gen or the inverter.
nice idea. I have a Fluke 325 - wonder if it will stay on for an hour or more waiting for the event to occur? Guess I'll have to try that one day.

The good news is that I went 6 months without calling on the generator. It took a five day storm to push the SoC to the start threshold. With a little luck I'll make it to next winter before this happens again.
 
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