driver0606
Well-Known Member
Hello,
Having discovered the hard way that lead acid batteries do not last long in a yacht that is regularly anchored at night, I have purchased four Optima blue top 75 amp hour AGM batteries for the service bank on my Azimut 43.
They are arranged in two pairs in series for the 24 volt system and are individually connected to the bus bar. The battery cables are not exactly of equal length, but are massive for the relatively light loads of maximum 50 amps. There is no volt drop in the cables.
What is strange is that the batteries connected to the positive supply show a higher voltage, both when being charged and when at rest, than the linked batteries connected to the negative supply. For example, after being fully charged and then left standing for 30 hours the one pair shows 12.79v and 12.62v, while the other pair shows 12.74v and 12.68v. In other words, the batteries nearest to the positive supply seem to be getting extra charge.
Any comments would be most appreciated.
Having discovered the hard way that lead acid batteries do not last long in a yacht that is regularly anchored at night, I have purchased four Optima blue top 75 amp hour AGM batteries for the service bank on my Azimut 43.
They are arranged in two pairs in series for the 24 volt system and are individually connected to the bus bar. The battery cables are not exactly of equal length, but are massive for the relatively light loads of maximum 50 amps. There is no volt drop in the cables.
What is strange is that the batteries connected to the positive supply show a higher voltage, both when being charged and when at rest, than the linked batteries connected to the negative supply. For example, after being fully charged and then left standing for 30 hours the one pair shows 12.79v and 12.62v, while the other pair shows 12.74v and 12.68v. In other words, the batteries nearest to the positive supply seem to be getting extra charge.
Any comments would be most appreciated.
