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richie-trent asked

Buck Boost ground wiring

We're installing a Buck Boost 100A in a current project. The Buck Boost only has one ground terminal. Other DC-DC chargers have two grounds for grounding your input source (alternator) and output (house system). So, should I connect the ground on the Buck Boost back to starter battery, or to the house system, or to both? I would think that if I split the connection and connected to both locations, the shortest path (ground to house system) would receive the bulk of the current. And if I don't connect to the house system ground, will the BMV shunt pick up the charging source, since it reads current going through the negative source?

battery charging
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wkirby answered ·

The negative terminal of the Buck Boost will be common to the negative of both batteries, the negative terminal of the start battery and the loads side of the BMV shunt.
See the schematic here: https://www.victronenergy.com/upload/documents/Buck-boost-schematic-2.pdf

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richie-trent avatar image richie-trent commented ·
So split the negative coming off the Buck boost, one leg to starter battery, one leg to house ground? Everything is eventually grounded to the chassis, so theoretically it shouldn't matter? I guess I'm wondering, if you didn't connect the Buck Boost to your house ground, would the BMV shunt pick up on the incoming current?
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