Hello. I am trying to troubleshoot my rec active BMS. I have been off of the boat for 2.5 months and when I got back my house bank (840ah lifepo4) was at 85%. The BMS did not have any lights on. I power cycled the bms (flipped switch, waited 60 sec, switched back on) and the green light is on; however, it is flashing in series of 3 times. I have rebooted Cerbo GX and power cycled Victron Multiplus inverter/charger. The Cerbo sees the rec bms and the multiplus is in bulk charging mode. The Cerbo display is alternating between charging, discharging or idle. I tried running the engine to see if the wakespeed/APS500 regulator would charge the batteries. Usually when the engine is running I will see a large negative DC load on the Cerbo (indicating charging), but I am not. The regulator indicator light is flashing yellow indicating that the charge current is under the control of the BMS.
I believe the BMS is not allowing multiplus, engine, generator, or solar to push charge to the batteries, but don't know how to resolve. It was working normally when I left the boat. Attached are screenshots of the rec bms display.
Hoping for a solution or any ideas what to check.
@stevehmick led flashes? error 3: did you checked manual?
To big unbalance, also your screenshot shows unbalance.
What is the setting, max allowed unbalance?
Something is charging the battery?
One cell is at 3.55V, means there is something charging!!
Also good to check, cerbo:devices/rec Bms/parameters. What is CCl and CVL.
This are the parameters the chargers will follow.
Your battery pack need a rebalance.
REC BMS will also balance your batteries, if all settings are correctly. And batteries are in reasonable condition.
Post all settings, folks on the forum can check or give suggestions.
Hey Steve, to expand on what Ben is saying.
Your BMS is in "Balance" mode as per the Green LED,
The system controls to the highest cell voltage so it is that one keeping it from fast charging until it balances your pack. If were to try fast charging that one cell would rise up until you got a hard trip, which is not encouraged. It is also possible you may have a weak cell so check your cell resistances to make sure they are fairly close.
If all goes well it should slow charge and balance your pack which could take a few hours or a few days. Keep an eye on the difference between cell min and max to make sure it is closing in.
From our quick start manual.
The green power LED signals the state of the battery pack. Low SoC is signaled by a single ON blink. Normal mode is signaled by 2 consecutive ON blinks while the balancing mode is indicated by 3 consecutive ON blinks before the longer pause. When the battery pack is fully charged and SOC/End of Charge Hysteresis are set
1 blink = low SoC
2 blinks = Normal mode
3 blinks = Balancing Mode
Solid LED = Pack full
