Schneider XW Pro won't qualify genset on AC2

[pvdude]

Finished the electrical work to connect the generator to the inverters.

Won't qualify the AC2.
Firmware is 1.11.01bn49

Anyone else have AC2 qualify OK on this version of FW?
What did you do to make it work?

The countdown timer expires, AC2 LED on the inverter control panel is flashing,
just never goes to solid green.
After 10 minutes, I shut down the generator.



Inverters report AC2 numbers that should be good. WTH

Also:
- AC settings - I left AC1 as priority, can't see how this would effect qualifying AC2.
- "generator support - enabled
- "generator support plus" disabled - I can't find any documentation on "plus".

(I suspect "plus" is like "double secret probation", and no one @ Schneider tech support will know about it)

 

[400bird]

I've heard lots of problems with generators on AC2

One thing I do know is that AC 1 needs to be missing/fail qualification for the inverter to switch to AC 2.

 

[MichaelK]

It's an issue with the quality of the incoming power at the default charging rate its set to. I don't have a gateway. I've been using the older SCP unit. The default charging rate of 100% on my XW+is 140A of charging current, which your generator most likely is not able to meet.

Go into the charging settings, and change the percentage to a very low value, say just 5%. Let the generator input qualify, then start incremementally ratcheting up the current percentage a few points per step. At some point in the ratchet trail, the generator will again start to stumble, and the inverter will drop it again. That tells you where to stop.

You'll have to play with the settings to find the point where everything works flawlessly. The generator fully warmed up and purring will help this process. Most likely, the percentage to "get qualified" is lower than the percentage to "stay qualified".

 

[pvdude]

One thing I do know is that AC 1 needs to be missing/fail qualification for the inverter to switch to AC 2.

I did try opening the AC1 breaker, early in the testing.
WIll try that again, now that I have changed some more configurations

default charging rate

I don't have charging enabled, the batteries are charged by the MPPT Charge controllers.
I'll try enabling charging and see it that has any effect.

 

[pvdude]

Changed:
"AC Settings" to make AC2 priority.
"AC2 (Generator) Settings to make the AC2 high frequency disconnect 1hz
higher than the AC2 high frequency time delayed disconnect.

Qualified OK and supporting the load!

AC1 is still connected, inverters just not using it.
With AC2 set as priority, AC1 operates as normal w/ genset shut down.
Powering up genset, AC2 takes over the load automatically.

Now to determine how to get the PV to contribute to the load.
As you can see, the system has decided to split the PV/batteries from the generator/inverters.



Normal operation:

 

[400bird]

Nice!
Is switching AC priority settings what caused the change in battery sourcing?

 

[pvdude]

Is switching AC priority settings what caused the change in battery sourcing

I suspect it has to do with the inverters - charging is disabled.
If the inverters don't know about the battery, I'm guessing they won't attempt to use them.
Possibly...never know w/ this goofy SW.
I will try to configure the charging features in the inverters next month, when the wife is traveling.
(Wife is tired of my messing about w/ the power here for the past few days)

 

[wheisenburg]

Now to determine how to get the PV to contribute to the load.
As you can see, the system has decided to split the PV/batteries from the generator/inverters.

I think your issue here as far as getting PV to help run the loads may just be that the AC1 and AC2 have different purposes.

AC1 - Serve as source / sink for current. The inverter will be in pass through or grid sell mode. When AC1 is connected harvest as much solar as possible. Charge the battery if needed, if not invert the current to AC and supply the loads. If there is still excess power, export it to the grid.

AC2 - Serve as source for current. The inverter will be in pass through mode. When AC2 is connected, supply the loads with as much power as they will draw. Additional power will supply the inverter which will go into charging mode and Charge the battery if needed.

So the purpose of AC1 is to supply power when the PV is less than the loads and to absorb power when the PV is more than the loads. It will also supply power needed to recharge the batteries after an outage.

With AC2, the purpose is to supply the loads and charge the battery when the PV is not enough to keep the batteries full. If the battery was at a low enough SOC you should see the charge controller feeding current to the battery. This would be true whether AC2 was qualified or not. If you enable the "Gen Support" mode you could see power coming from the batteries/charge controller to limit the current drawn from the generator. But again this mode is used to charge the batteries from the generator, so pulling power from the DC system should happen only occasionally to cover peaks and only when gen support is enabled.

Normally when running the generator it will draw what is needed for the loads, plus what is needed for the charger. Once the battery is full, the generator would be turned off. Since you cannot "Export" power to a generator, any current coming in through the inverter must be controlled so that the inverter power is always less than what the loads are consuming.

 

[RxJemm]

I really appreciated this clear & concise explanation!

 

[AOCSkooney]

Thank you for this. I struggled getting AC2 to qualify, and did as you suggested and it all worked. Were you able to get your charger working? I have been battling all weekend with this. I can get it qualify, then it begins charging my batteries, but the inverter makes a very loud humming sound. In battery settings I have been playing with the BULK Charge current, and once I exceed 30amps, the inverter trips out after a couple minutes. At 22.5 amps it runs for about 30 minutes then trips out. Any suggestions? I'm trying to upload photos now, as everything seems nominal.

Schneider System XWPro - Using a 12.5kw Peak Champion Generator (could it be dirty power from generator?)