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joebedford's avatar
joebedford
Nomad III
Jun 04, 2015

12V plug in for inverter

Anybody else notice that if you draw near the max rated power for your inverter that the ciggy plug cable gets QUITE hot?

10 Replies

  • 1775 wrote:
    These little inverters are not intended for what some want to power with them.


    But still (try to) do it anyway. :S

    For those who do want to do it right the solution is simple - just refer to a DC Wiring Chart like this that will tell you what gauge and length of cable is required for the maximum load you intend to draw. Since I (current in amps) is calculated by dividing P (power in watts) by V (volts, in this case a nominal 12 vdc) it's easy to calculate the correct wire gauge - e.g. a 300 watt inverter drawing full load would draw 300/12 = 25 amps. Look at the chart and that will tell you what gauge cable you need for the length you want to run.
  • We had a fairly good inverter that not only caused the 12 volt outlet to get hot but also the inverter itself (which had a fan) got very hot. These little inverters are not intended for what some want to power with them.
  • Ron3rd's avatar
    Ron3rd
    Explorer III
    joebedford wrote:
    Anybody else notice that if you draw near the max rated power for your inverter that the ciggy plug cable gets QUITE hot?


    That's why I hard wired my 300w Samlex PSW inverter. Came with the plug, but I threw it in a drawer.
  • RoyB's avatar
    RoyB
    Explorer II
    It will melt your solder on the connection. I wouldn't do that unless you get a matched BLUE SEA PLUG and SOCKET rated for a specific current rating.

    All of my battery connections are using terminal lugs just for that very reason.

    Roy Ken
  • If it is a 300 watt inverter it would love to draw 30 amps running flat out. Cigarette lighters were never intended for that sort of load.
  • Yes just as expected with any circuit drawing near max rating.
    Get some #6 wire and a 50 amp connector and everything will cool down.
  • being strictly a power related question

    it was moved from technology corner
  • Ciggy lighter outlets are usually rated for 10, maybe up to 15amps
    That translates to 120 to 180 watts.
    MOST inverters are going to push that limit so yes, they will get hot! What is the rating on yours and what are you powering with it?
    Inverters (other than very small ones) SHOULD be hard-wired (with a fuse) direct to the battery with heavy wiring to handle the current draw.