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nebulight avatar image
nebulight asked

DVCC with external third party charger?

All my parts are showing up to get ready for an install into my camper van and it just dawned on me about DVCC and third party chargers. This will not be an ESS. I have a VenusPI, Multiplus 3000 12v, MPPT100/50, BMV712 and a 50 amp DC to DC charger that I'm using to charge from my starting battery/alternator. I setup Venus for DVCC to limit the amount of charge going to the battery. As I understand it Priority goes to MPPT over grid. However how will the system react when the charge source is coming from a DC source like mine? For example lets say we set the max to 60 amps. I start the engine and start getting 50 amps from the DC-DC charger, would the MPPT be limited to 10 amps?

Venus OSDVCC
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mvader (Victron Energy) avatar image
mvader (Victron Energy) answered ·

Hi, the system won’t know anything about those 50 amps coming from an uncontrolled charge source.

And therefore the total charge current will exceed your setting.

Ofcourse, in theory it might be possible to use the BMV current reading to overcome this limitation; but thats not so easy to make stable; and hence we’ve decided to not go there.


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nebulight avatar image nebulight commented ·

Is there any future for your own dc to dc buck boost converter to be added to the Venus since it has CAN? I know it’s a rebranded product so the protocol may be different but that might be an option down the road. Might be nice to have all my charge sources talking to each other plus the summary screen would look neat with a alternator icon! ;) I didn’t opt to go with it since it didn’t communicate with the Venus. If that changes maybe down the road I’ll swap it out.

But in all honesty I don’t think I’ll ever hit that limit. I was just asking to know the limitations as my bank is 400ah so I’d be setting the limit to 200. I just though of worse case is I run the battery flat if I had access to shore AND it was mid day AND I started the engine for the fastest charge possible. Even so max charge I could get would be 220 amps and I’d never get the full 50 amps out of the mppt as is have 600w of solar so that’s 43 amps max. Real world max is maybe 30 amps. So maybe 120+50+30 I’d be right at or around 200.

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