My setup will be have three LiFePO4 battery systems:
1. 12v generator start battery - 1P4S LFP battery + REC ABMS + 60 amp alternator + (Cerbo?)
2. 24v main engine start battery - 2P8S LFP battery + REC Q BMS + 70 amp Balmar Alt + (Cerbo?)
3. 24v house bank battery - 2 x 4P8S LFP batteries + 2 x REC Q BMS + REC 9M + 220 amp Balmar alt + (Cerbo?)
Can I connect my (3) REC-BMS and Wakespeeds WS500 to a single CERBO GX or do I need one for each battery system.
Hi @MeltemiCaz
I personally would go with one cerbo for the system as a whole and then multiple smart shunts for monitoring all the various batteries.
Smart shunts have different DC meter modes now (see Page 28 below).
Manual - SmartShunt (victronenergy.com)
I'd configure them for each of their purposes and just have the main battery show up as the battery on gui but have sensors on other two to monitor their soc/monitoring the charging/discharing.
I've only worked on houses though so dont know if there's a go to solution for this, but this would be my best guess.
Thanks for the reply. My system is for my sailboat. It has three alternators that are managed by Wakespeed WS500 smart regulators, 3 separate REC Bms systems that are used to control and protect each of the three batteries.
My question centers around having all of three of Wakespeeds, and the REC-BMS devices on the same bus by being tied to one Cerbo GX.
I do not yet know or understand it this is possible or advisable. The two 24v batteries are generally kept separate but there is a parallel switch that can be used to tie the two 24 volts systems together for emergency operations, for example if the start battery for the main engine becomes depleted. Joining the house bank to the start bank will all me to start the main engine. I am looking to simplify the set up for single point monitoring.
Also be very careful about having all BMS and Wakespeed on the same buss. You will need to make sure that the Wakespeed and BMS instance IDs work and that the write pair are communicating. Not something I believe is recommended, multiple separate battery banks with BMS and Wakespeed sharing a bus.
I personally would leave the starter batteries as AGM using the stock alternators to charge. Additional alternator on engine with WS500 for main house battery bank. If you want a DCDC between starter battery and house to make use of spare capacity on the starter battery/alternator
I would think a single cerbo is fine, as Matt said - unless those REC BMS systems can talk to victron, I'd go with a single Cerbo and then a smartshunt on each battery, that will give visibility over what the 3 circuits are doing.
I don't have a lithium setup on my boat, but I do have 3 different power circuits and 3 batteries.
For my two start/house circuits I run smart shunts (they charger via a 240V charger + alternator from each engine).
I have a victron phoenix charger than connects to all 3 batteries and that also gives me visibility on all the batteries (the 3rd battery is for the generator).
Having a single cerbo is not going to bridge the circuits if that is what you are worried about.
From Rick Bell Off Grid Marine Energy:
"I don't think you can mix voltages without a system voltage error so the 12V unit may be an issue. I know the cerbo can monitor several packs at a time but only one can be the DC source.
I don't think you will damage anything if you give it a try. Your WS500s will also need to be given separate CANBus addresses so they don't try to go into a master/slave config."
How large of a boat and what type is this?
For the starter batteries, there is no need to monitor their SOC, or is there? Monitoring voltage, and then more specifically you as an operator seeing that they get charged when the engine runs should be plenty good.
Maybe have a two simple Victron IP65 AC chargers, powered from an inverter on the house bank, charging those two starter batteries. Super simple and effective. Alternatively you could use a small dcdc charger for the same point. And why not have simple lead batteries or drop in lithiums for those starter batts? Instead of self built + rec bms + wakespeed?
Usually such devices (REC + Wakespeed) are only used for large size battery banks and high output alternators.
Less parts to fail, more time to sail.
Now if you whish to keep them all in the plan: for the RECs I’m not sure if you monitor them all on one Cerbo. Probably not.
For the WS500 it should be possible.
And one more thing, if the REC disconnects the battery, when there is an issue, lets say over-voltage, then its important that the alternator has stopped charging already. there is a feature for that between a Victron Lynx Smart BMS and a Wakespeed. You have to make sure the same exists between REC and the WS500. The GX is not not going to interface between them for that.
Simply put: such “stop now!” signal is time critical, and if it goes wrong your alternator and possibly other devices can break, and we don’t want the GX /Victron to carry such responsibility. It needs to be handled between the alternator + lithium bank. Either hardwired or via comms (canbus).
