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dreader3's avatar
dreader3
Explorer
Jul 31, 2015

6V Deep Cycle Batteries

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?

20 Replies

  • RoyB's avatar
    RoyB
    Explorer II
    Another sure way would be to PRINT a large PLUS and MINUS on piece of paper and tape them to the correct cable using CLEAR TAPE...

    I went and purchased a new JENSEN RADIO a few years back and it came with RED and BLACK terminals so when I installed that inside the trailer I ended up with a RED TERMINAL over a BLACK TERMINAL in the junction box. That sure looked strange to we old timers haha...

    Roy Ken
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Suggestion.. Get either two bottles of Nail Polish -OR- two small cans of spray paint (or two large cans) one RED one Black

    With the batteries PROPERLY connected spray the positive terminal with RED (or brush it on) Overspray onto the battery is a good thing if spraying, Dripping red paint (or just flat brushing it on) the battery likewise.


    Use black on the Negative end

    now red painted wire to red painted battery terminal. Black to black, Unpainted to Unpainted and your job is always going to be right.

    Now,, the winter storage.. Did you use a Battery Minder (TM) or Battery Tnder (TM) or a trickle charger (Junk) to maintain the batteies?

    There are several different devices.. When I waS a child our only choice was a trickle charger, these low-amprage chargers had no regulation and depending on teh size of the batteires and the size of the charger either over charged or failed to maintain (IN THEORY you might hit one that worked 100% but odds are against it like 99.9 to 0.1)

    Today we have two more editions
    One is an automatic slow charger,, It charges 'em up and shuts down

    The other is the Battery Minder/tender 2-stage automatic charger (Absorption/float) these continuously monitor and will switch back to ABSORPTION (Charging) if necessary.

    READ the instruction manual because what I posted is a generality.. not all products work as well as others.

    But do paint both the wires and the battery in the area of the terminal (or and the terminal itself) to insure red to red.
  • Dakota98 wrote:
    Your 6-volt GC batteries need an occasional "equalization" charge. The Schumacher SE-70MA charger will not do this.

    Maybe I need to equalize mine. I never have and the T-105's only last me a little over 8 1/2 years.

    How much longer will they last if equalized?
  • 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.
  • 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!
  • 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's avatar
    RoyB
    Explorer II
    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
  • Most likely connected in reverse. Longshot would be charged in reverse.
  • Did you accidentally charge the batteries to reverse polarity? Check to see with a meter.

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