Prevent MPPT 100/30 from Low Temp Charging -- Upgrade BMS to V2 for DVCC?


(Image uploaded, I think.) It is the first image on the old VE Bus BMS V1 data sheet showing
Smart Lithium Batteries
Digital Control Panel
VE Bus BMS V1
Multiplus
Smart Battery Protect
I also have Cerbo GX and Smart Solar MPPT 100/30

The Victron system in my van looks a bit like this image above, with the addition of a Smart Solar MPPT 100/30 and a Cerbo GX. It has 3 Victron 200 ah Smart Batteries.

I recently found that the MPPT was trying to charge the batteries even though the VE Bus BMS V1 had its low temp light on (2 of the batteries were ok, 1 was too cold). Upon inspection, the MPPT was not getting a temperature number from the VE Smart network – only voltage and current. I installed a Smart Temp Sense device on the coldest battery and enabled it to report via VE Smart the battery temperature. My MPPT controller now has the temperature from the Smart Temp Sense Device.

Was this the right solution? The Smart Shunt 2nd terminal was not available for a temperature sensor. One of the negative battery terminals has, I believe, a temperature sensor on it that goes to my Multiplus but that data was not making it to the MPPT.

I have another related question. It seems like I should have DVCC turned on in my Cerbo to integrate my alternator+solar+ (infrequent) Multiplus charging but looking at a data sheet for my old BMS V1 I don’t think the Cerbo can talk to the V1 BMS and hence DVCC won’t do anything. Is this right? Should I install a VE Bus BMS V2 and turn on DVCC? If I do, what happens to the Digital Control Panel?

This van mostly gets charged from the Cyril Li CT and the MPPT, FYI.

This system was not installed by me so I am still learning. Should I acquire a USB MK3 to talk to the Multiplus? I know next to nothing about it.

Thank you.

The system also has Smart Shunt in it, to be clear.

Victron has 2 methods to disable charge via a mppt when the battery reports a low/high temp issue to the VE Bus BMS.

First method is to use the “charge disconnect” output of the BMS to control the mppt via a VE.Direct non inverting remote on/off cable

The second option is to use the “charge disconnect” output of the BMS to
cut the output of the mppt via a Battery Protect.

If any battery should experience a low (or high) battery temp, the battery will signal the BMS to disable charging.