6V Deep Cycle Batteries

[dreader3]

I'm Using 2 deep cycle 6 volt batteries wired in series in my trailer. I bought the batteries last fall after the camping season was over for us. I put the batteries on a 12v trickle charger over the winter to keep them charged. When I initially installed them this year they still were not charged very well. After a couple of trips where I couldn't keep them charged I bought a Schumacher SE-70MA deep cycle charger to charge the batteries. When I reinstalled the batteries in the trailer and switched on the battery it blew two 40 amp and one 15 amp fuses immediately. What gives?

[Dakota98]

Your 6-volt GC batteries need an occasional "equalization" charge. The Schumacher SE-70MA charger will not do this.

Quote from the manual:

10 Amp 12 Volt setting: The initial charge current should be 10 amps
gradually tapering throughout the charge cycle to 5 amps. Though not
indicated, battery voltage will gradually rise to approximately 14.3 volts,
then hold constant throughout remainder of charge cycle. When the battery
reaches 14.3 volts and charge current drops to 5 amps the charger will turn
off. Initially the battery voltage will drop from its 14.3 volt level fairly
quickly. When 13 volts is reached, the charger will again turn on, until the
14.3 volt, 5 amp condition is met. As this action continues, on time will
decrease to a few seconds while off time increases to a range of several
minutes to an hour. on/off times vary with size, type and condition of
battery.

[dreader3]

Hey everyone, thanks for your help. When I read the first reply regarding connecting improperly, it hit me like a lightening bolt that this is probably exactly what I did. I did check the batteries water level and it is fine. I also checked each cell with a hydrometer and everyone looks fully charged. Thanks again for your advice!

[CA_Traveler]

In addition to the above you need to get those batteries charged ASAP. A full winter w/o being fully charged means they have lost some life. You could also have a bad cell. How is the water level?

Have them load checked to find out their condition.

[RoyB]

Not hard getting the leads REVERSED as the connectors on the battery terminals are the same type.

If they were reversed you may have blown two FUSES in the 12VDC Distribution Panel labeled 'REVERSE POLARITY' and then another in-line fuse close to the battery bank.

Don't feel bad blowing the fuses as that is why they are in there - to protect from us guys hooking them up in reverse. No Harm DONE... Just blown fuses... You are not the only one that has done this haha...

Be sure to correct the wiring before you replace the fuses otherwise they will just blow again...

I always look for the word 'NEG' or the symbol '-' Stamped into the outside 6V battery case and make sure this is he battery terminal that goes to FRAME GROUND...

The normal trailer wiring colors will be BLACK for positive +12VDC cables and WHITE for negative -12VDC cables. They may white cables and the ones with color stripes will be positive leads...

Sometimes however they will be using the AUTOMOTIVE Battery Colors which is RED for positive +12VDC and BLACK for negative -12VDC cables.



Roy Ken

[time2roll]

Most likely connected in reverse. Longshot would be charged in reverse.

[pianotuna]

Did you accidentally charge the batteries to reverse polarity? Check to see with a meter.