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bhamlyn's avatar
bhamlyn
Explorer
Jun 27, 2015

Possible converter problem?

We just got our TH last year. We have a 2004 Carson toy hauler 20". We have used it about 4 times last year. Everything worked well.

We are getting ready to use it for the first time this year. I hooked up to shore power and everything works fine except I notice that the converter charger runs all the time. When I shut everything down last night it was still running, I pushed in the switch that is suppose to disconnect the batteries from the trailer and the converter still ran. When I unplugged the trailer from shore power the converter turn off.

Do I have a problem? My battery monitor says the batteries are all charged. We did not have the batteries on a trickle charger over the winter but we did start the truck numerous times and just let it run for a while.

Thanks for any help!!!
  • Thanks, everyone, for your help. I appreciate your comments and suggestions.
  • bhamlyn wrote:
    Westend - I believe I thought that the parasitic draw was eliminated when I pulled the switch that disconnects the batteries from the trailer. Is there still a draw when the batteries are disconnected?
    There shouldn't be any draw from the battery when the switch is in "disconnect" position. You can also verify this with a meter.

    I'd suggest that the next time you're close to a Harbor Freight store, stop in and pick up a cheap meter. Even if you have never had one in hand, it is a good tool to have. The learning curve is slight and if you never get around to using it, a fellow camper or neighbor may be able to help you if it's available.

    As you get more familiar with your 12V system, you could perform some upgrades like installing inexpensive panel meters, 12V access ports, LED lighting, and other sundry conveniences.
  • Understand that the converter's output is 12V DC. As such is responsible for charging the batteries, and providing 12 VDC power to lights, pumps, blowers, and some electronic boards. It does not power the microwave, refrigerator (except for the electronics), water heater (electric side only), and the Air Conditioner. Some of the OP's responses he seems confused about this....
  • rrupert wrote:
    bhamlyn wrote:
    Westend - I believe I thought that the parasitic draw was eliminated when I pulled the switch that disconnects the batteries from the trailer. Is there still a draw when the batteries are disconnected?


    No


    Depends on how disconnect switch was connected.

    Some only disconnect main battery cable to converter and leave LP Detector, jacks, landing gear wired directly to battery with there own in-line fuses.

    So some parasitic drains can still happen with disconnect off.
    Again...depends on how switch was wired in
  • bhamlyn wrote:
    Westend - I believe I thought that the parasitic draw was eliminated when I pulled the switch that disconnects the batteries from the trailer. Is there still a draw when the batteries are disconnected?


    No
  • Westend - I believe I thought that the parasitic draw was eliminated when I pulled the switch that disconnects the batteries from the trailer. Is there still a draw when the batteries are disconnected?
  • Yes, the fridge has a 12 volt mode but I turned the fridge off, knowing that it was running on shore power and getting it's power thru the converter. The only other power draw was the number "0" on the microwave.

    I just went back out and plugged the shore power back in and the converter did not come on. I then connected the battery and it still didn't come on, so maybe the batteries are fully charged finally.
  • Anything that you have that is 12 volts that is turned on will draw power through the converter. So if you have the battery disconnected and the device is turned on it has to get its power from shore power through the converter. Do you have a 12 volt mode on the fridge?
  • Thanks for your help. I really didn't know about the parasitic draw. Thanks for letting me know.

    Will it hurt the converter to just let it keep running or at a certain point do I need to worry.

    Thanks so much for your help.
  • Chances are, even if you had the battery disconnect switch in the disconnect position, turned it to connect and infrequently charged it with the truck, the batteries will be discharged quite a bit. It may take the converter many hours to charge the batteries back to full.

    Those idiot light meters (if that's what you have) are known to be inaccurate. Check voltage with your meter. That will also tell you if the converter is supplying voltage to the batteries.

    You do know that if the batteries are left connected to the trailer system, the parasitic draws of devices inside will discharge the batteries within a week or two?

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