sma inverter kicking off

[Rtholen]

I have two sp6 us 41 sma sunny boy inverters. One will kick off after one or two hours of running and says over voltage slow and this will happen on a cloudy day. Called sma and have talked to them a total of 3 hours. They can't figure it out ether. I'm running #6 copper from inverters to my production meter. I've checked all connections to make sure their tight. It's always the same one kicking off. Just wondering if anyone ever had this problem. It's like they can't work together. Thanks

 

[NVS]

Did you try to swap them? If it still happens you'll know it's the inverter.

 

[RCinFLA]

AC overvoltage can be caused by grid voltage being too high or having too much GT power pushed into too long, and/or too small gauge wiring from GT inverter to AC panel feed. Also make sure you don't have a poor connection or circuit breaker going bad.

Then there is possible panel input DC overvoltage.

 

[Hedges]

Inverter display or a DMM would let you see if line voltage is near upper limit (assuming this is grid tie.)
There may be different settings which could work, e.g. Rule 21 might have more voltage headroom.
Some parameters aren't supposed to be altered for compliance.
A buck-boost transformer can raise or lower voltage 5% to 10%, the hardware equivalent to changing parameters.