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crcr's avatar
crcr
Explorer
Apr 10, 2013

Question about Installation of Morningstar Inverter

I am installing a Morningstar SureSine 300 watt inverter in my TT. Below is a pic of a page of the installation manual. My question is regarding the Earthground terminal, item #1 in the DC connections to the inverter.

I am installing this in the pass through storage of my TT opposite two golf cart batteries on the tongue. The aluminum framework in the pass thru, per my meter, has 100% continuity with the TT frame. So would it be OK to attach the Earthground lead to that aluminum framework rather than the TT frame? The lead can be shorter that way.

Thanks for any input.


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  • KJINTF's avatar
    KJINTF
    Explorer
    Apr 10, 2013
    Yes 12awg wire will do the job just fine
    Remember at 300 watts and a short term max of 600 watts that translates to more more than 5amps - 12awg wire can easily handle that - do not forget the inline fuse.

    From my experience that nice little inverter outputs a nice clean 110Vac not any higher so do not be surprised if you look at the AC with a voltmeter
  • BFL13's avatar
    BFL13
    Explorer II
    Apr 10, 2013
    One of our actual electricians can confirm/deny, but AFAIK with the 300w inverter you will be under 15a output and could use 14/3. AFAIK 12/3 is for 20a circuits.

    I use a 30ft 14/3 extension cord from the 2000w inverter to run the microwave, which only needs a 15a circuit. Doesn't get hot or anything.
  • crcr's avatar
    crcr
    Explorer
    Apr 10, 2013
    Thanks very much, BFL, one more question -- the manual says to use 12 gauge wire coming off the 110v output posts. The run is only 3' or a bit more, to an RV plug, where I will plug my shore cord in to activate the 12V outlets in the TT. For 300 watt, 12 gauge would be more than adequate, wouldn't it? I don't need to use 10 gauge, do I? I hate wrestling with the 10 gauge romex wire unless I really need to.
  • BFL13's avatar
    BFL13
    Explorer II
    Apr 10, 2013
    The chassis ground goes to the frame (your aluminum same thing) but do not run it over to the Dc neg input to the inverter (big no-no)

    The DC neg input eventually connects to the frame too, via battery neg, but that is ok, don't worry about it. Just go to the frame direct.

    The chassis ground is meant to reduce any radio interference caused by the inverter. Deck mount converters have a chassis ground too that goes to the frame.

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