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kingpleb asked

Cerbo GX with seperate CANBUS cables & MPPT units

Hi all, I've been lurking for a while and now have a question to ask I can't find anywhere else.

I have a Cerbo GX and a MP2 15k inverter with a 14kwh Seplos Mason (V2 BMS)

I'm looking to add another battery to this setup and cable it to the spare posts on the MP2 but if I can source well priced 15kwh units with a V3 active balancer for less than a V2 + additional active balancer.

This introduces a problem as the V2 & V3 BMS units can't be stacked directly together, but I'm wondering if I can just put the CANBMS cable from the newer unit, into the spare CANBUS port on the Cerbo GX.


Is this feasible at all or will the Cerbo GX have a hissy fit about 2 different BMS units into 2 ports and expect them to be daisy chained?



Also I'm looking to add an RS MPPT unit in the future, but would this really need to go in a LYNX distributor and then the batteries connected to there as well and just 2 cables from the Lynx to the MP2? The latter seems to be the cleaner way to do it, but adds another device into the setup...

cerbo gxBMSseplos
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1 Answer
nickdb avatar image
nickdb answered ·

With the exception of the latest models, cerbos don't have different buses, those 2 BMS ports are the same bus, same as VECAN, has a common bus with multiple ports. So you are daisy chaining no matter what.

Regardless, the cerbo will only use one BMS, the other is purely for reporting stats.

Most of this (if not all) is in the manuals.


Wrt wiring, have a read of the wiring unlimited guide, it has all the answers you need and is the best place to start.

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