Relay to mppt ‘remote on/off’

Q&A and troubleshooting
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Hi, wondering if anyone may be able to help here … I have a new smartsolar mppt (450/200) … all working well, no problems. I have a new JK bms that I bought because it has programmable dry contact relays on it that are ‘normally open’, the problem is that I want to send a two wire signal to ‘ remote on/off’ on the mppt to tell it to stop charging when a battery cell voltage gets too high for example. If the relay on the bms was normally closed this would work perfectly as the relay would open the circuit on the ‘remote on/off’ thereby stopping the mppt from overcharging the cells. But … the relays on the bms are the other way around, they are normally open and when they get triggered by whatever parameter you program (high cell voltage in this case) the relay closes … effectively doing the complete opposite of what I want it to do. Is there anyway to work around this on the victron side of things (with two wire bms selected) or any other way that anyone may know of or can think of ?

Any help appreciated, thanks.

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It would be best to connect the data to a Cerbo, and have that control the MPPT and other chargers on the system, that way, the charge current can be tapered down as the cells approach max voltage, allowing balancing to take place.
If you can’t connect the BMS data directly, have a look at Louis VanDerWalt’s software that allows integration with the Cerbo.
Using relays to shut off solar charging should be considered an ‘emergency’ procedure, in case of failure of normal regulation.

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