question

bret-marro avatar image
bret-marro asked

Cerbo GX compatibility

Hoping this question makes sense. I am upgrading an old 48 volt tubular gel set-up (20.6kwh) to a 48 volt lithium 15kwh (5 x Genz 3kwh, internal BMS only, marketed as a lead acid drop-in replacement). I currently have a Latronics LS-3548 3.5kw inverter which is used 99% of the time and a Victron 5kw Multiplus inverter/charger which is only used for heavy load items in a workshop and the occasional charging via a generator. The whole house is completely off-grid with a 4kw solar array arranged in 4 strings. I am replacing the solar charge controller to a lithium compatible one and believe the Victron MPPT Smartsolar 250/100 TR and a Victron Cerbo GX bundle with touch screen and a Victron Smart shunt 500amps should do the job. I am hoping this will enable me to monitor the battery state of charge and control other external devices via a relay, eg water heater when in float and to also view remotely. I am wanting to keep both inverters as they are working fine and are connected in a simple parallel circuit with the respective outputs connected to each one.

My question is, if the Cerbo is not connected to either of the inverters via the VE cables will it cause any issues regarding the system's performance? I am hoping it will see via the shunt all incoming and outgoing current from the batteries and be able to keep track with what is going on. So both inverters would be just a load on the battery system. Also, if the batteries were getting low and I had to run the generator, I understand the Multiplus does not have a lithium charge parameter so I would just use it to get the voltage out of the danger zone where it would remain in bulk mode. Hopefully that isn't an issue either.

Any info is much appreciated,

cerbo gx
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

1 Answer
Paul B avatar image
Paul B answered ·

First of all yes it will work fine as you are suggesting it will work stand alone and work with the gen autostart.

However of note all the Multiplus and Quattro units have lithium charge profiles.

and secondly I would still connect the cerbo to the multiplus 5000 via VE.Bus as this will allow you to see what its doing , battery SOC etc is always shown from the shunts current in and out.



1 comment
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

bret-marro avatar image bret-marro commented ·
Great to hear. Thanks a lot.
0 Likes 0 ·