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liquidspaceman's avatar
liquidspaceman
Explorer
Jun 05, 2013

400W Inverter Installation... Questions

Hello,

I would like to get one of those off the shelf 400W inverters to power a television in the dinette area that my daughter can watch while on the road without having to start the generator. I currently do not have any 12V recepticles so that's the reason for the inverter install.

My question is, can I just run this inverter directly to the house battery or would I need a fuse somewhere along the chain? I am not planning on plugging any coffee makers or hair dryers into this plug, it is strictly to run the television and that's it.

I was just thinking of taking some wire and running it to the back of the coach and just attach it to the positive and negative terminals on the house battery.

Am I doing this wrong? Any concerns with this setup? Thanks in advance.

9 Replies

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  • Z-Peller's avatar
    Z-Peller
    Explorer
    Jun 06, 2013
    Yes, fuse between battery and inverter, and fuse should not be more than 18 inches from positive battery terminal.
  • mena661's avatar
    mena661
    Explorer
    Jun 06, 2013
    I would NOT use the cigarette lighter. The wiring on those is notoriously small. Those things are really only meant to run really low power devices not 400W inverters.
  • KD4UPL's avatar
    KD4UPL
    Explorer
    Jun 06, 2013
    To answer the original question, yes you definitely need a fuse in the battery connection. NEVER connect a wire to the battery without a fuse in the positive lead. If there is ever a short in the wire a fire will likely result.
    A 400 watt inverter will pull nearly 40 amps at full load. This will require #8 wire at minimum. Larger would be even better. A 50 amp fuse should be enough. If you run larger wire you can increase the fuse size appropriately.
  • hershey's avatar
    hershey
    Explorer
    Jun 06, 2013
    Of course its always a good idea to keep the inverter close to the battery and the 120 volt cord longer to the appliance.
    But if all your going to run is a TV with a small 400 watt inverter, you can use an available cig lighter socket for 12 volt power.
    Anything larger you would be better off mounting as suggested above.
  • time2roll's avatar
    time2roll
    Nomad
    Jun 05, 2013
    I suggest a 150w to 300w.

    You can mount behind the power panel and use the main 12v battery connection.
    Wire the 120v side to the single circuit with a small transfer switch.

    I only recommend sine wave. MSW usually works, SW always works.
  • Just_Jeff's avatar
    Just_Jeff
    Explorer
    Jun 05, 2013
    You want your 12v cables to be as short as possible...so put your inverter right next to the batteries (but not in the same compartment because of gasses).

    Then make your 120v extension cord do the long run from the inverter to the TV.

    The reason is you'll get a lot more voltage drop with low-voltage (12v) cables than with 120v cables. It's a lot more efficient use of power this way.
  • 2oldman's avatar
    2oldman
    Explorer II
    Jun 05, 2013
    liquidspaceman wrote:
    So install the inverter in the bedroom and then run an extension cord?
    Are the batteries in the bedroom?
  • 2oldman's avatar
    2oldman
    Explorer II
    Jun 05, 2013
    liquidspaceman wrote:
    t thinking of taking some wire and running it to the back of the coach and just attach it to the positive and negative terminals on the house battery.
    No. Put the inverter close to the battery and make the 120v run long.

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