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[stevenc1603]

Bit of an odd one for me this.

I am putting in an office in the summer house.

In order to get power out there I have purchased and run in some 3 core SWA cable.

Now I know that the wire colours have changed, but with 3 core I expected to find a brown, a blue and a something else.

In actual fact I have a brown, a black and a grey, which to my understanding is the colours for 3 phase. Where is the neutral wire?

While I know its probably not to regulations I intend to use the brown as a live, the black as a neutral and the grey as an earth. I'll tag the wires with the correct designations before they are terminated by a sparky.

I was just wondering why there appears to be no neutral wire in this cable?

Cheers

Steve

[kuzz]

Because those were the colours that were agreed to replace our red yellow blue by Europe. Don't agree with it as now we find ourselves with a black neutral & a black live if adding to a three phase installation.

However Identify the cables with the correct colour sleaving as i'm sure your part p electrician will & no prob.

[stevenc1603]

Cheers for that Kuzz,

I don't think we have Part P up here in Scotland, but there's bound to be something similar. Either way its the spark doing the termination of that bit anyway.

[sparx]

Hi,steven,
IET [old IEE] state should use : brown as Live, Grey as Neutral[sleeved blue] And black{sleeved grn/yel.] as Earth. Idea being to break association between blk & N as in 3ph system is now a Live core colour.
The reason they don't make a brn/blk/grn/yel swa is they expect you to use a 2 core cable brn/blu with sheath as earth.
Most 3 core is used for balanced 3 ph circuits using swa as Earth [CPC to give its correct title] where no neutral used.
So limited call for 3core on single phase circuits.
(unfortunately some smaller sizes of SWA don't meet CPC requirements for disconnection times due to small amount of armouring around thin 2 core so no choice but your way) B,W, SPARX

[stevenc1603]

Cheers for that sparx. I was aware that the outer wire armour was normally used as the earth, however as its feeding the summerhouse I wanted something a little better so went for the three core.