Forum Discussion

zul's avatar
zul
Explorer
Apr 22, 2014

Simple Inverter Setup Test - FAIL>?

A friend gave me a 2000w/4000w peak Coleman Inverter.
I hooked it to a 70ah excide battery with some thick jumper cables: good wire connectors to the +/- attached to the inverter for good contact. Alligator clips connecting the cables to the battery. Is this connection 'good enough'? Or is it important to have solid connectors on both sides?

No seperate ground... hmmm.?? Wondering if that is OK?? Problem?

For the test: a 1500w hot pot to boil some water. Nothing. Not working. Unpluged it from the inverter and pluged it into the wall. Still not working (we used the hot pot yesterday). Did my experiment blow the appliance? It could be a coincadence but I fixed the hot pot by pulling it apart and moving a clip into place. Now the hot pot works on the wall plug.

Did the inverter blow the hot pot?
Can I expect a 1500w appliance to run on a 2000w inverter?
What are some better testing ideas so that I can best understand the inverter? ... without blowing appliances.

THX!
  • DutchmenSport's avatar
    DutchmenSport
    Explorer
    Apr 22, 2014
    I would retest with a simple light bulb in a simple lamp. If the bulb blows, you haven't lost much. If you plug in an appliance, you might be spending money ... on a new appliance and a new inverter!
  • MrWizard's avatar
    MrWizard
    Moderator
    Apr 22, 2014
    1500w appliance, approx 13 amps @ 120v
    Equals 130 amps @ 12v
    Quite possible not enough battery, the inverter simply shut down from low voltage when to try powering the low

    Possibly #2, hotpot has digital controls, that did not like the wave form power out put of the inverter
  • Chris_Bryant's avatar
    Chris_Bryant
    Explorer II
    Apr 22, 2014
    Not enough battery, need better connections than clamps. Agree try a small load, then move up.
  • GordonThree's avatar
    GordonThree
    Explorer
    Apr 22, 2014
    I would agree the battery is insufficient to deliver needed current, and the connections insufficient to carry the needed current.

    Use a bigger battery, with bolt on / clamp on connectors to the inverter.
  • 2oldman's avatar
    2oldman
    Explorer II
    Apr 22, 2014
    zul wrote:
    A friend gave me a 2000w/4000w peak Coleman Inverter.
    Is he just generous, or is there something wrong with it?
  • Gdetrailer's avatar
    Gdetrailer
    Explorer III
    Apr 22, 2014
    1500W load is 12.5A at 120V, that inverter would have been drawing at least 125A if not 130A at 12V. Simply not big enough battery AND those jumper cables tend to be rather long along with on the wimpy side (6ga or even 8 ga).

    To successfully operate heavy loads you NEED extremely heavy ga 12V wiring AND it must be as short as possible (6ft including pos and negative wires).

    As someone else noted, try a light bulb (any wattage up to 100W should work)..

    As far as your coffee maker.. can't help you on that I don't drink coffee..
  • zul's avatar
    zul
    Explorer
    Apr 23, 2014
    Yes, this is a free inverter from a generous friend.
    Works as far as we know, we don't have a manual and I don't think this Coleman model is made anymore :(

    I can shorten the cable and install good ends/connectors.

    The old test battery is the old 12v travel trailer battery.
    My new TT batt are 2x6v @ 215ah. Would that set of batteries provide proper juice? The batts are new ... Will these type tests damage my new batteries??

    I'll give it a try with the light bulb on the old batt and work from there... So much to learn!!


    Thanks for the help!
  • time2roll's avatar
    time2roll
    Nomad
    Apr 23, 2014
    Not enough battery and not enough wire for 1500 watts.
    If the heater has any electronic controls it may not like the modified sine wave (MSW). Incandescent bulb does not care about MSW.

    Heavy jump cables would be 1 awg like these:



    You really should have 400+ amp hours to drive that inverter.

    If you plan to use it to watch tv fine but to run a heater I think your battery will be dead before you feel much heat.
  • MrWizard's avatar
    MrWizard
    Moderator
    Apr 23, 2014
    to boil water use a ordinary tea kettle

    OTH 60~90 seconds in a MW will make a CUP hot enough for instant coffee
    or heat up cold coffee

    i will use the inverter late at night for a "warm up" sandwich coffee etc

    but during the day i will use the generator, saves on battery and is more efficient than draining then recharging the batteries

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