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moomps's avatar
moomps
Explorer
Aug 07, 2014

Battery Question

Let me first start out with this disclaimer - I know NOTHING about the electronic workings of my TC. I have a 1990 Sun-lite 850WT. There is not an installed battery in the TC, but one of the former owners (I was told - it might be factory original) put a plug in the outside drivers front side to allow the hookup of a battery. The TC has an inverter built in and almost everything works great in whether 120 mode or with a battery hooked up to this plug. Now my question - in battery mode, all the lights and fans work great, but the water pump doesn't come on. Under normal circumstances, should the pump work in this mode too? Is it possibly wired wrong, or should it even work on 12 volts?
  • Sorry for the wrong terminology. The situation is that the pump works fine with 120, but won't work with 12 volts. So, as MEXICOWANDER suggested, I'll attack the wiring in the Converter and see of the pump is wired correctly or maybe there is a fuse problem. Either way, at least I know that the pump "should" work with 12 volts as I suspected. Time to put on my detective hat and see what's up - and learn something about RV wiring.
  • Its called "converter" not inverter.
    The lites and water pump runs on 12 volts, whether from a battery, or thru the converter when plugged in. It sounds to me like if you plug in a battery, you good to go !
    Yep, the water pump, same as lites, is 12v. If it don't run, look for fuse, switch, wiring, or defective pump.
  • It Depends Whoowee...

    Most RV converters have the DC fuses in them as well. But that makes no sense in this case.

    Look for a wacky design hookup FUBAR style that has each 12 volt accessory wired to both the converter and the plug (Y splits to two power sources) except for the water pump which only has a path to the CONverter DC connection.

    After summer when you feel energetic, take a half dozen images of the entrance point of the external battery socket (the feeder wires running everywhere) and the converter wiring (behind the converter). It might be a rat's nest because the former owner made "some modifications".

    No sweat. You have a simple to understand and explain system once images are put up on this forum :)
  • moomps wrote:
    is the pump 12 volt and the inverter steps 120 down to 12 for normal operation?
    The converter does that.
  • I figured it should work on 12 volts too. It works fine on 120, is there a seperate fuse that would affect 12 volt operation? I'll check the panel tonight, but is the pump 12 volt and the inverter steps 120 down to 12 for normal operation?

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