MPPT stops charging with DC load at 100% battery

Q&A and troubleshooting
, , , ,
1

I have a Victron system in an RV with a Quattro, Lynx BMS & distributor, smart lithium batteries, Cerbo, MPPT, 165 amp alternator and Wakespeed 500 voltage regulator connected via CANBUS. All running the latest firmware updates. DVCC enabled

When driving, the alternator and solar charge the batteries. As the battery gets up to 100% the solar reduces and stops completly when the batteries are at 100%. The alternator continues to charge at whatever the DC system is drawing, usually 40-80 amps. Typically the air con fans are running, the inverter is powering the refrigerator, etc.

I would like the solar to continue to provide whatever it can and the alternator provide the rest. Am I correct in thinking with a BMV-712 set as a DC Meter and the shunt on the coach DC load cable the solar would then be enabled to power the DC loads, even with the battery at 100%?

The 712 shunt would have to go on the coach load negative cable. The Lynx distributor has 4 connections, Quattro, MPPT, Coach Load and alternator. The Quattro and MPPT are, I think, isolated to chassis ground. The alternator does have an isolated ground, it’s currently going to chassis ground, but I could wire it straight to the Lynx. So unless I’m missing something the shunt will see the entire coach load.

Is this the best way to accomplish this or is there another way?

Thanks

2

I believe that the DC system measurement allows DVCC better control. Also, do you have DVCC selected in the WS500 settings as this will be required to back the alternator off. I would hope DVCC gives priority to solar but I have not got my system fully working yet to confirm.

3

Yes DVCC enabled on the WS500. I’m using the WS app to set up the regulator. By the way, the WS500 has a shunt on the alternator positive cable to measure output. I would think since the WS500 is charging there would be a way to allow solar priority when driving.