question

xmd avatar image

Charge starting battery: BMV 712 relay vs MPPT SmartSolar Load Output

I have an older PWM charge controller which will charge both the House and Starting batteries. I am getting more solar panels and want to upgrade to MPPT, but MPPT charge controllers generally do not support 2 battery banks.


  • Assume I start with a single MPPT SmartSolar or BlueSolar controller


What would be the best solution?

  1. I could use the Load Output and wire that directly to the starting battery, and set a rule for the Load output to turn on the load when the house battery is between X and Y volts. Pros: doesn't require more equipment. Cons: the bigger MPPT controllers don't have the Load output at all, so I'd have to stay with the lower capacity models.
  2. I could get a BMV 712, and use its relay output to control a relay which connects the House and Starting batteries, and use a similar voltage-based rule (On between X and Y volts)
  3. Some other Victron product - battery isolator or combiner or...?


Thoughts?



MPPT - Solar Charge ControllerBMV Battery Monitorstarter battery
2 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

0 Answers