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smsinville's avatar
smsinville
Explorer
Sep 29, 2019

New 6 volt golf cart batteries seem not to be charging

I have a Heartland Edge trailer...21 ft...year 2010. I've had no issues with the single 12V house battery. We're planning a trip that will involve lots of boondocking, and so I've put in two 6V golf cart batteries; the gel kind. AFter that install, the battery status showed "full". As a "test", I turned on some lights and a 12V fan to see how long I could power them. AFter 3 days the simple battery status gauge (stock one, with tank status lights) showed about 2/3. So I plugged back into shore power to check recharging. Even after 5 days the battery status is still at 2/3. It appears the power center is is not recharging those batteries. Any idea what could be wrong? I do plan to use a multimeter to see what the 12V wire leads show, what the two batteries show. Maybe I just need a more sophisticated battery status indicator?
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Sep 30, 2019
    Wired wrong. Breaker tripped.. bad battery and where did you find "GEL" 12 volt RV size batteries.. They don't make GEL in the sizes we use in fact they don't much make GEL any more.. AGM yes but not GEL

    And if you bought OPTIMA (which is sometimes marketed as GEL even though they are AGM) you got ripped off only 2/3 the capacity of standard AGM batteries at 4/3 the price or more.

    NOTE: Gel are very finicky eaters You charge them as fast as I do my Flooded wet's and they die and die fast.. AGM's on the other hand are the opposite. you can charge them same as Flooded. Some makes even faster.
  • opnspaces's avatar
    opnspaces
    Navigator II
    Sep 30, 2019
    Your wiring gauge is not the problem, especially not the short wire connecting the two batteries together. My trailer has 6 gauge wire between the batteries and from the charge to the battery about 20 feet away and it charges fine.

    You mentioned you have a multimeter. Unplug the trailer and run the furnace blower for 3 minutes, then turn it off. Take a reading at your batteries, if you have the ability also take a reading at the circuit board for the converter charger. Then plug the trailer back in and take readings at both the charge controller and the batteries, and let us know what you find.

    I'm betting you have a loose ground or a blown reverse polarity fuse. but you won't know anything until you take some readings.
  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    Sep 30, 2019
    A good way to start is with an excellent diagram showing cable connections to 4 golf car batteries. For things like connecting the battery condition meter to one pair of batteries and connecting the charger to the other pair.

    Start off simple where most mistakes are made, please.
  • smsinville's avatar
    smsinville
    Explorer
    Sep 30, 2019
    I certainly appreciate all the quick responses. I am certain it is wired correctly as that is a simple pattern to follow. However, I used a four gauge wire for the interconnect and I am seeing today in some comments and research that I should have used a two gauge wire. I have not yet checked the circuit breakers and fuses and I will do that. But I’m thinking maybe the gauge of the interconnect wire might be a factor. Anyone have an opinion on that?
  • opnspaces's avatar
    opnspaces
    Navigator II
    Sep 30, 2019
    Make sure you wired them in series. You can ignore the battery disconnect in the diagram if your trailer doesn't have one.

  • beemerphile1's avatar
    beemerphile1
    Explorer
    Sep 30, 2019
    New install? You connected them wrong or simply left a wire off. Redo your install.
  • agesilaus's avatar
    agesilaus
    Explorer III
    Sep 29, 2019
    Our progressive converter has three reverse polarity fuses, same principal tho. Check the breakers. Progressive tells you to remove the positive cable from the converter then check the output. If it is 12V then it is working, if not it isn't.
  • Boon_Docker's avatar
    Boon_Docker
    Explorer III
    Sep 29, 2019
    Two things to check.
    1- Make sure the circuit breaker for the converter is not tripped.
    2- Check the two reverse polarity fuses on the converter (30 or 40 amp fuses).
  • BFL13's avatar
    BFL13
    Explorer II
    Sep 29, 2019
    New batteries, good opportunity for a reversed polarity which pops the converter fuses for that. (maybe two 30a fuses on the DC fuse panel or else on the converter)

    So you are on battery with the wires reversed, the lights work, but the fans run backwards.

    If red and white, red is pos. If red and black, red is pos. If black and white , black is pos.

    The battery monitor is a rough voltmeter. A full battery is 12.7v, so the converter at 13.6 will show as full even if the battery is nearly dead. With no converter (as now) it will show the actual battery state (roughly)

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