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Powerwall 2 + UPS Connundrum - and solution

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Although I don't have a tesla power wall, I would like to throw some info out here for ya'll. I have a SMA sunny island ac coupled with two Sunny Boys. When my batteries are full, I "lie" to the Sunny Island about what the SoC is to compel the SI to join the grid. It's a bug, or rather an omission in their firmware... the only time it'll connect to the grid is when the SOC is low. Never the less, the SI blips the frequency to 64hz for about 1 second to make sure the sunny boys stop production. Then it syncs with the grid and turns on the grid contactor. At that point, the sunny boys also sync with the grid and start making power that is exported. We know this happens every day because I head the UPS on my server rack click and go on battery for a moment. During normal runs when I prohibit it from connecting to the grid the frequency never goes over 62hz.


Just an FYI if it helps.... 64hz seems to be an industry standard to "really really really" make sure AC coupled inverters stop.
 
Just out of curiosity, did you get a chance to check to see if your override is still there?

No, I havent taken the time to take myself off grid to check it. I was going to check it with my kill a watt type device but that requires me to take my house off grid to check, when my batteries are full. I dont consider the app "go off grid" to be a real test, so it means throwing my main breaker.

I kind of need to do this early on a weekend morning before my wife gets up and when we are not using much power. Since summer weather is here where I live (was close to 100 the past couple of days), not sure when I will do this now.
 
No, I havent taken the time to take myself off grid to check it. I was going to check it with my kill a watt type device but that requires me to take my house off grid to check, when my batteries are full. I dont consider the app "go off grid" to be a real test, so it means throwing my main breaker.

I kind of need to do this early on a weekend morning before my wife gets up and when we are not using much power. Since summer weather is here where I live (was close to 100 the past couple of days), not sure when I will do this now.

I was mainly curious if you still had the override in the /api/site_info. I no longer have that setting but I assume that it still is a good indicator.