Posted by Peter Kennedy on 2/8/2022 to System Integration
To demonstrate what happens when you have multiple DC voltages and want to connect them to a Cerbo GX I set up a demo system with a SmartShunt connected to a 12 volt battery and a BMV 712 connected to a 24 volt battery. This is a very simplified demo system and that is all that there is in the system. Note that for this to work both systems must have a shared negative connection. I connected my system to the Victron VRM to make it easy to get screenshots from the virtual console.
In the screenshot above it chose the 12 volt SmartShunt to appear on the main page and then in the device list shown below you can see both battery monitors appear.
In the screenshots below you will see that you can go to an individual page for each device to see the details:
If you want to swap the system around you can make the 24 volt system appear on the main page as shown below. This is done in the System Setup page where you get to select which device is the primary battery monitor.
As there are two separate shunts through the negatives, where do the two differing systems share the negative connection?
Yes you need two different shunts to do this. In my example one was a BMV 712 and one was a SmartShunt. The two connected to a common negative busbar to which all the loads and charge sources also connected.