My AGM batteries are getting a bit tired and I am swapping them out for 400ah of lithium, 2 - 200ah 'drop in' replacements.
My system has the 3000 watt inverter and Truecharge 40+ shore power charger which the boat came with and I have verified with the battery manufacturer that these will work with the lithium (they said to set the shore power charger to GEL - WARM to get the right charging characteristics). I have also installed solar a few years back so will need to adjust the charging parameters of the Victron MPPT controller and I am installing a new victron DC to DC charger to protect the alternator.
The question I have is on the battery switches. My thought was that all charging sources would be on the "House" side of the switches so you can turn off battery power to the charge sources if needed. Since I see that mine is wired to have charging sources go to the battery side of the positive and negative switches, I have verified that both my new Victron DC charger and Victron MPPT charger controller have internal fuses, so I am a bit more comfortable installing the charging sources on the battery side of the switches.
However, when I had the negative battery switch in the off position, I tested it with the amp meter and noticed that both sides of the switch where grounded to the battery. It seems some dealer installed ground wires go directly to the battery side of the negative switch which may be inadvertently grounding the entire system.
So 2 questions to the group:
1) is your charger installed on the "battery" side of the switches?
2) Has any one else experienced the Ground Switch issue described above? Any reason to have anything besides the charging & battery ground wires on the battery side of the switch?
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