Can the relay function on the smart solar mppt solar controllers be used to trip a shunt trip circuit breaker - specifically for an over voltage situation? Under voltage protection isn’t a concern as the lifepo4 BMSs and the inverter low voltage cutoff is enough protection. But I am concerned if one of the mppt goes full open voltage it would probably instantly destroy the BMSs and then start cooking around 120kw of lifepo4.
Not sure that is agreat idea. Using the thing you want to protect against to do the protecting.
The bms should also be able to protect against high voltage as well (to spme degree)
But for OVP look at SPDs or the smart battery protect (remebering that is is unidirectional)
Can the relay function of a victron inverter/charger be programmed to trip a shunt trip CB? I want to disconnect the solar if there is a mppt failure and open voltage up to 250vdc suddenly appears at the bms/battery. Trip the CB at say over 60vdc?
Circuit breakers trip on over current not over voltage.
The likelihood of a sudden failure on the mppt if you have sized your panel array correctly is not very high.
For overcharge on the battery side the mppts usually short their input side.
If you are really concerned, you can swap them out for the Galvanically isolated 450/100 MPPT. Even if you install a ground fault protection device, it will only indicate that you have the full 250VDC on the battery side.