any sparkies on here? quick question

longun

longun

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hullo,my garage is about 35m away from my house and am gonna fit armoured cable underground.

the garage will have 4 strip lights and about 6 sockets

i may use a welder for short periods once in a blue moon

so the question is,will a 4mm 3 core be suitable for my purpose? the lads at work just say yup,should be!! but id sooner ask for other opinions :D

this is what i rek ill buy if its ok
http://www.screwfix.com/prods/85106/Ele ... Cable-Reel

cheers :D
 
id go 6mm....reasons are...
distance from the main supply to secondry outlet.....
if your demand for current increases you will have the available capacity allredy rather then having to upgrade the cable again.cheaper in the long run fella.you need to know how much current the welder will suck up to make an accurate caculation...the s/o and the lights arnt much of a problem(2.5 tw&e will be fine for just them)...we do have other sparkies apart fro myself hereif that helps one is called "johnthesparky" i think..
 
hello,

I'd assume the welder to be maximum 16A, so say you fit a small garage unit at garage with a 20A and a 6A MCB,

design current of 26A
length 35m

so if you did it with 4mm, the volt drop would be too great, but with 6mm volt drop would be about 6.6V so would be fine!!

but you only need a 2 core 6mm swa, as you aren't allowed to use the supply earth for the outbuilding, just run the live and earth to the garage and earth the SWA at the house end (but insulate the gland at the garage end) and then bang a 4' earth spike just near the garage and earth to the garage unit with a 4mm earth. You'll need an RCD at the garage end for this to conform to regs, but most garage units have an RCD and 2 breakers anyway....


hope this helps

John
 
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