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mwi13 avatar image

Peak Power Pack and SmartShunt: can I tie all grounds together?

I would like to track the state of charge of my Peak Power Pack, something which is sorely lacking (for the price I kind of expected something like this to be included, actually!). The difficulty is the different current paths, I have the charger connected, the car/solar connector is also connected, and of course the load is connected to the "mover" output. Can I tie all the "minus" connections together (charger, car/solar, load, and possibly even ve.direct ground), connect this to a smartshunt, and then connect the smartshunt to the PPP? In other words: the minus of the charger adapter, the car and the load are connected to the load side of the shunt, and the other side of the shunt is connected to the mover output minus of the PPP.

BMV Battery MonitorsmartshuntPeak Power Pack
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More or less same question here. I like to use the BMV-712 for monitoring the Power and the Domestic output.

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Mike Dorsett avatar image
Mike Dorsett answered ·

Basically you have the right idea.

With the smart shunt, you can treat the load terminal as the common ground and the battery minus terminal as an active terminal. In other words, ONLY the battery negative gets connected to this - no other wire, ground or anything. The battery minus also needs to be insulated from ground. This way the shunt monitors the battery current properly.

The ground wire of the VE direct serves 2 functions - a power return for the isolation ic in the VE-direct 'receiver' and as a screen for the data. It is not necessary (or useful) to make any additional ground connection to the VE-direct cable, as this is likely to set up a ground loop and either add noise or a dc offset to any readings.

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Thanks for your answer, sorry for the suuuuperlate reply :') the caravan is stored and I kinda forgot about my battery questions. Also, never got a notification mail apparently.

Good to know that the general idea is correct! The only worry I have is that the minus of the two charging input is somehow not directly connected to the minus of the battery output. I probably could measure it, except if there's for example a shunt in between somewhere that's going to be hard to detect with my somewhat cheap multimeter. I might try to open it to check, that would answer the question for sure, but not sure if that's possible without damaging it ...