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Aussie_Travelle's avatar
Aussie_Travelle
Explorer
Jun 28, 2016

RV 12volt Power Supply

We have a 2000 Shasta Sprite motorhome which has a problem with the 12volt power (note we are not connected to shore power). At night and early in the mornings when the cool weather happens the DC power trips out and may come back on in ten minutes or in several hours. We have investigated and there is a drop in voltage to around 10.5 to 11.5 or no reading at all, at the battery disconnect switch, although the one week old battery is reading 12.5v. We have also tested the inline 50amp fuse and it registers 12.5v. The Parallax convertor has had the bottom half replaced in the last two weeks. Is there another solenoid etc that we are missing ? Any other thoughts.

Graeme & Jennifer.
Class C
  • Aussie_Travelle's avatar
    Aussie_Travelle
    Explorer
    Jun 29, 2016
    Thanks to everyone for replies.

    We have looked at many of the connections in the convertor and they are OK, actually bi-passed the disconnect switch and it made no difference so we think it's ok, but may replace it in any case.

    Yesterday we located the ground wire and traced it to the chassis and took it off, sanded it and the connector and the chassis and last night was cool and we got out of bed at 3am and it didn't trip out. Got up this morning and made the bed and it didn't trip out - fingers crossed.
  • YC_1's avatar
    YC_1
    Nomad
    Jun 28, 2016
    It sounds like a loose wire on the converter. The slightest movement is probably making it come and go. Tighten all the screws that hold wires there.

    Temperature changes can make terminals tighten and loosen . It only takes a tiny bit with 12 volts.
  • tenbear's avatar
    tenbear
    Explorer
    Jun 28, 2016
    Mine has a circuit breaker in the battery to the battery disconnect solenoid, under the bed. It went bad and I replaced it. I replaced the old converter at the same time. All is well now.
  • ronfisherman's avatar
    ronfisherman
    Moderator
    Jun 28, 2016
    Check all the connection to converter. You should not get a short when getting out of bed near the converter. Did you replace converter with a another from the same manufacture. Many have replaced it with a PD4600 upgrade.
  • Aussie_Travelle's avatar
    Aussie_Travelle
    Explorer
    Jun 28, 2016
    thanks corvetteken.

    All the terminals at the battery and disconnect switch are clean and no build up anywhere.

    Although the voltage readings on the input and output sides of the disconnect switch are the same (whether high or low) we were considering replacing that switch.

    Where would we find the ground for the battery ? Can we re-ground to the chassis?

    This morning when we got out of bed (convertor is under the bed)the power tripped out as we put weight on the bed frame and floor !!, which happens most mornings! any ideas - may be a short circuit ?

    It does not trip out when it is warm, but when the night air starts to cool, then it starts to trip.

    Aussie Travellers
  • corvettekent's avatar
    corvettekent
    Explorer
    Jun 28, 2016
    Clean the battery cable connections at the battery, disconnect switch and ground. You also may want to replace the disconnect switch.

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