ben asked in Home & GardenDo It Yourself (DIY) · 2 months ago

I want to wire a 400w floodlight to cable and plug, my question is what size 3 core cable, type, and what amp fuse?

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  • 2 months ago

    not sure where you live ben ..but here in the uk electricity is expensive ..my 500w security had a standard 3 core cable with 13amp plug ..standard ...but i replaced with a 20w LED lamp ...just as much light ..96%saving on electricity

  • y
    Lv 7
    2 months ago

    Amps = watts over volts.

  • 2 months ago

    normal 15 amp fuse [north america] is fine. the thing only draws 4 amps maximum. cable size depends on length of the cable and you'll not go wrong if you use cable rated for 15 amps [12/3] and the circumstances you expect to use it in [outdoor?]

    Source(s): grampa
  • 2 months ago

    Your voltage matters, Lord Nose sounds right for 230v, but for a typical general purpose receptacle in the US I would use 16/3 SJOW cord, and typically no fusing would be required unless specified in the installation instructions.

    The geeky regs that influence my answer: The NEC Article 400 governs cord types and amperage allowances. A 400 watt bulb and ballast at 120v should use less than 5 or 6 amps, Table 400.5(A)(1) column B for cables with two current carrying conductors allows 10 amps on #18 awg wire, I would use (bigger) #16 because #18 awg is just too tender to work with. Your local hardware store should have something similar to SJOW (Service Junior Oil Water), but I would need at least cable with an S and W rating. 240.5(B)(2) would likely be the applied section allowing 100 ft. length for the #16 on a 20A protected branch circuit or 50' on #18.

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  • Anonymous
    2 months ago

    Connect into a ring main with a switched fused connection unit. Use a 30 amp three way junction box using 2.5 mm three core cable. Wickes sell short lengths. Run a 1.5 mm three core cable from the fused spur to the light. Insert a 3 amp fuse. Or you can connect into a lighting circuit as 400 watts draws less than 2 amps. A third method is to plug straight int a 13 amp socket using a plug fused at 3 amps. But this is untidy. The first method is best,

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