I have 4 house battery
banks on the boat.
Previous owner says the batteries are about 18 months old.
-#3: two 6-volt Trojan T-105s
-#4: two 6-volt Trojan T-105s
I can never get the voltage on any bank to go above 12.4 volts, no matter how long I run the chargers. Useful charge duration seems to be way too short, banks 1 & 2 will barely last overnight with very little load (occasional head
& FW pump use, one courtesy light bank). Banks 3 & 4 are better, as I'd expect, but still do not seem to last as long as they should.
I saw a previous survey
report where at least one battery
bank was found dry. I suspect I need to replace all batteries but don't want to waste money
I have 2 chargers connected to the 4 house banks PLUS the engine
starting battery. Engine
cranking seems fine. Curiously enough, the genset battery has no charger
connections at all other than the genset alternator
The chargers are a mismatched pair, one is a smallish Pro-Mariner solid state unit and the other is a much larger unit whose manufacturer I cannot remember. When starting both chargers I get an initial charging
amperage of 90A. I've not yet verified how they are connected but they logically must be in parallel. I get charging current
to all 4 banks using one charger
or the other, which seems to confirm that.
How do I tell for certain the true battery condition? Is a hydrometer the only way or is there another discharge test I can run? Or do I just bite the bullet and start over - I also have doubts about the chargers installed and will likely replace them.