Forum Discussion

Cougarnewbie's avatar
Cougarnewbie
Explorer
Jan 19, 2016

Inverter. What am I missing?

We would like to boondock over night in cold weather. I want to power a Harbor Freight 2000w. modified sine wave inverter from my 5ver battery, than plug in my trailer's 30amp power cord to my WFCO 8955 converter into the AC plug on the inverter. Would the inverter have enough wattage to use the converter to keep the battery charged and run the 12 volt furnace and a couple of 12 volt lights? Seems like a continuous loop. Use battery to power inverter. Inverter to power converter. Converter to keep battery charged and enough to run furnace. My guess is no, but I don't know why.
Thanks
AL
  • valhalla360's avatar
    valhalla360
    Navigator
    Jan 20, 2016
    Most RV furnaces run on 12V, so leave the perpetual motion machine (aka: inverter) out of it.

    Likewise, a lot of the lighting is often 12V.

    If you want to run the TV or other AC (alternating current) device an appropriately sized inverter is a nice addition but you can't just plug the 30amp plug into it or it will run the converter (battery charger) with power pulled from from the battery. Since there converter and inverter are not 100% efficent, they will eat up your limited battery power.

    Based on your question, I would suggest having someone experienced set up your system.
  • DrewE's avatar
    DrewE
    Explorer II
    Jan 20, 2016
    N-Trouble wrote:
    What are you wanting to power with this 2000W inverter and what do you have for batteries? Trying to understand your end goal here.


    The end goal was pretty clearly stated, I thought—basically to break the law of conservation of energy and produce electrical energy out of nothing. It's a nice goal to have, but not very realistic.
  • N-Trouble's avatar
    N-Trouble
    Explorer
    Jan 19, 2016
    What are you wanting to power with this 2000W inverter and what do you have for batteries? Trying to understand your end goal here.
  • time2roll's avatar
    time2roll
    Nomad
    Jan 19, 2016
    The result will be a dead battery. You need a couple solar panels if you want to put energy into the battery. If you decide on a generator you will also need a new converter and a second battery.
  • bikendan's avatar
    bikendan
    Explorer
    Jan 19, 2016
    2oldman wrote:
    Cougarnewbie wrote:
    Inverter to power converter. Converter to keep battery charged and enough to run furnace. My guess is no, but I don't know why.
    Perpetual motion machines don't work. No, you can't charge the battery using the same battery.


    Exactly!
  • 2oldman's avatar
    2oldman
    Explorer II
    Jan 19, 2016
    Cougarnewbie wrote:
    Inverter to power converter. Converter to keep battery charged and enough to run furnace. My guess is no, but I don't know why.
    Perpetual motion machines don't work. No, you can't charge the battery using the same battery.
  • pianotuna's avatar
    pianotuna
    Nomad III
    Jan 19, 2016
    Plugging shore power cord into an Inverter.

    1. switch fridge to gas
    2. switch water heater to gas
    3. switch converter off
    4. plug in shore power cord to the inverter.
  • llr's avatar
    llr
    Explorer
    Jan 19, 2016
    If the converter is left on it will shorten the battery life, not add power.

    Everything has loses so even if the inverter and converter are each 90% efficient which is probably high you will only but 8 amp into the battery for every 10 amps taken out

    if the converter has its own breaker turn it off, otherwise find another method

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