Controlling XW Pro charge-off grid with legacy PV

[Don B]

Hello,
I'm trying to find someone familiar with Schneider systems. So far, tech support with Schneider proved fruitless.

I have 3 kW of legacy Solarbridge PV/grid tie inverters. I'm off grid and no generator. I have the Insight Facility and battery monitor. My battery is 13.4 kWh lithium NMC. It has internal BMS, but I want to use SOC to engage the panels at or below 70% (using Aux port 12+), then decouple at 90% SOC.

I have equipment running that should not have frequency shift applied, so I want to use the XW Pro Aux 12+ to control a contractor in the PV supply input. I can't find correct settings in any of their manuals. I have tried various settings, but can't figure how to get the SOC trigger to work on the Aux 12+ output.

I will gladly pay if anyone is familiar with Schneider settings. I have tried a couple companies recommended by Schneider, but no luck. Two hours with Schneider tech support didn't help because I seemed to know more about the equipment than the tech support guys who were simply flipping through the same manuals, trying to find details that seem to be left out. Until I get this step figured out, I'm simply using the PV manual disconnect to control charge, but I have to be home to monitor the SOC to avoid battery damage. Luckily, I'm retired, but it means that I have to shut down the panels when I won't be here and empty the fridge and shut down the system when going out of town.

Any help is appreciated.

[Mike90250]

> I have equipment running that should not have frequency shift applied

Wow. You must have some fancy stuff that can bee affected by the minuscule Fq shift. Something like a GPS master clock transmitter ground station ?

What will people do when the Grid does Fq shift to knock off all the excess solar ? Will automotive plants grind to a halt ? No.. The "shift" is minuscule. An analog clock may gain a second or loose one per day.

[bcroe]

When I got a radio for WWV in the 50s, I used it to set my electric
clock. I found the PoCo might drift up to 7 seconds in a day. But
there was no use resetting the clock, because the PoCo would
drift back the 7 seconds the next day.

I suspect controls more recently are a lot tighter, when the grid is
not under great stress. But I use atomic (radio) clocks now. I
wonder what shift would knock my solar inverters off, probably a
huge shift. Bruce Roe

[J.P.M.]

When I got a radio for WWV in the 50s, I used it to set my electric
clock. I found the PoCo might drift up to 7 seconds in a day. But
there was no use resetting the clock, because the PoCo would
drift back the 7 seconds the next day.

I suspect controls more recently are a lot tighter, when the grid is
not under great stress. But I use atomic (radio) clocks now. I
wonder what shift would knock my solar inverters off, probably a
huge shift. Bruce Roe

I did the same at about the same time in the past and was about 10 yrs. old when I was told that the clock phenomenon was due to the drift of the phase angle in the power coming into the house. Since that loss of power off into the imaginary plane cost the POCO some revenue, I was also told they tried to keep it to low levels. Since accuracy is now much more important for reasons not even conceived of back in the 50's, I think that problem has been solved.

[Don B]

Mike90250 The manual says it will shift up to 64 Hz. That doesn't sound miniscule; any idea how that happening repeatedly each day might effect a minisplit heat pump or energy star appliances? Without being a real engineer, it sounds like it's worth avoiding possible problems. One of Schneider's manuals also cautions against using frequency shift because it will cycle often. I had some 60 hz motors on equipment we took to Australia years ago. The master electrician tried to convince me it was ok to run them on 50 hz. In less than 10 minutes the magic smoke escaped both motors. I don't think that only 4 hz would be that drastic, but I don't want to guess.
My microinverters are legacy, so while it will trip them ok, it will not gradually reduce the output as frequency shift is designed to do. Using SOC control from 70% to 90% should only cycle once or twice per day.

[bcroe]

4 HZ is a heck of a shift. A 50 HZ motor needs more iron, so it will
not saturate on the longer cycle. Once it saturates the iron becomes
invisable, there is a BIG increase in current, and things get really hot
fast. A 60HZ motor might be used at a much reduced voltage at 50HZ,
reduced hp out, if you do not mind it turning 17% slower. More eddy
current might be a problem. Bruce Roe