ACR working?

[max from alaska]

Ranger Tug 2014 R27: I plugged into shore power and charged the batteries for several days. The voltage readout for bank 1 and 2 showed a little over 13 V. I disconnected the shore power and immediately disconnected all the wires to all batteries then removed them from the boat. About 2wks later I measured about 13.2V with a multimeter on both house batteries. But the engine battery was at 12.45 V and the thruster at 12.5 V. Ideas on cause? ACR not charging engine first? Or are the engine and thruster batteries just bad? Would appreciate troubleshooting ideas.

 

[Jared Dunning]

First, if the battery voltage drops too low, the ACR may interpret it as a dead battery and prevent charging from reaching it. To bypass this, turn on the parallel switch — this will trick the ACR into allowing charge to flow to the batteries until their voltage rises. Once the batteries reach a higher voltage, the system should begin operating normally again. Second, you could have a faulty ACR. If you turn on the parallel switch and the ACR still doesn’t activate, it’s likely that the ACR has failed.