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cdstaley asked

Parallel dc sources

Can the output of a mppt be put in parallel with the output of a dc~dc converter charger.. why? Because you need power added to lithium bank while plugged into shore power. Let’s say you sleep late and the solar starts pumping power. Who’s going to win. Will they fight each other?

MPPT ControllersOrion DC-DC Converters not smart
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shaneyake avatar image
shaneyake answered ·

They will work together. The current from MPPT + Current from charger = Current to battery. So just make sure that battery can handle the current from both.

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cdstaley avatar image cdstaley commented ·
Is that based on an analysis of the circuits of both systems, or observationally. I'm pretty sure that they will work, but I don't know for how long. That formula is for kirchoff's law is what you stated. Kirchoff's voltage law, or the conservation of energy law zero's out voltages in a loop. Since resistances are different in the MPPT, the DCDC, and the internal battery and I think those devices are voltage devices, the current will adjust to get a loop voltage of zero. This means the current's will vary potentially putting excessive current through one or more the the items in the loop. I was sort of hoping that Victron staff monitored this site and an engineer could confirm the succeptability or lack of, of over current issues. Not worried about the battery as the combined current couldn't exceed what the lithium can sink, but thanks for you answer. If you are an engineer at Victron please confirm to validate your claim of compatibility. Thanks again!

cds


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