Fuse size - help please

Discussion in 'Tech/Mech General' started by Barclaybasher, Aug 8, 2012.

  1. Barclaybasher

    Barclaybasher Funster

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    I have fitted a Waeco 500w inverter to my van, through a fuse holder but not sure size of fuse to use.
    Spec for inverter is:
    12v input - 220 output
    continuous power 500w peak power 1000w
    Help please
     
  2. JeanLuc

    JeanLuc Funster

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    The fuse is there to protect the cable and ideally you should use one that is rated a bit higher than the likely current. If the fuse is a lot bigger than it needs to be, it will only fail when things get dire.

    The formula you need to apply is amps = watts/volts.
    So for your inverter the rated maximum current will be 500/12 = 42 amps
    but the maximum peak surge (depending on what you power with the inverter) could be 1000/12 = 83 amps.

    If you are unlikely ever to draw more than 500 watts from the inverter, a 50 amp fuse should suffice. If however, you plan to use it's surge capability (albeit only for a few seconds) you might need a 100 amp fuse. I presume the cables you have used are adequate for the current being drawn? If in doubt, the attached may be of use (it's from Sterling Power Products).
     

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