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BMV-712 Relay to switch off DC to DC Charger and MPPT remote ON/OFF Pins

Hello, could anyone give me some information regarding the best way to set up Relay on the BMV-712 for use in my Campervan


I would like to use the BMV-712 relay to switch off my Victron DC to DC charger & my Victron 150 | 60 MPPT via there Remote ON/Off ( L & H ) pins in case of Low battery temperature ( or another trigger I wish to use ) . I have temperature sensor for the BMV and want to use the low temperature trigger to trigger the Relay.


Wiring wise what would you recommend? What output on the BMW and which pins in the Dc to DC & MPPT should I use?


Just so I'm getting this Correct the "L" pin Supplies a 3.3v Live, When the "H" pin Receives a voltage of 3v or higher it turns the device on, and less the 3V it turns the device off? If this is the case could I Ignore the "L" pin on the devices and Wire a 12V live from the Battery into the COM port of the Relay and then just Parallel the "H" pins from the NC relay port. when the Relay in the BMW is normally closed the charger & MPPT would be ON, when the low temperature triggers ( or any other trigger ) , it will open the relay which would turn off the Charger and MPPT ( and prevent my lithium battery is charging when cold and my Batteries internal BMS doesn't have low temperature charge cut off ) 

OR would I use DC/DC Charger & MPPT L pins in Parallel wired to the COM relay port on BMV, then NC relay port wire in Parallel to the H pins on the charger & MPPT.

Since I want to control both the DC/DC charger and the MPPT remote On/OFF at the same time from the BMV relay. Running the output ( NC ) In parallel to multiple things shouldn't be an issue should it?


Cheers
-Alex
BMV Battery MonitorchargerRelayswitch
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1 Answer
wkirby avatar image
wkirby answered ·

Your first explanation is correct.
Wire the H pin of both MPPT and DC-DC to the NC contact of the relay. The COM of the relay to battery +.

Alternatively, you can wire the L pin of both to the NC of the relay and then the COM of the relay to battery -. When L is connected via NC relay to battery - then the devices will be on.

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