Armoured Cable Question

[HERTS P&D]

Hi Guys,

I hope my questions are not too stupid.

On a 1.5mm 4 core armoured cable, the colours are brown, blue, black & grey.
Brown is live and blue is neutral, black and grey are extra for lighting? or is one used for an earth?

On a 2.5mm armoured cable there are 3 wires, brown, black and grey. Which one is neutral?
Shouldn't there be a blue wire like in the 1.5mm wire.

Is it ok to use the outer cable as the earth?

Andy

 

[OwainDIYer]

The 4-core cable is intended and coloured for three-phase + neutral, using the armour as an earth.

The 3-core cable is intended and coloured for three-phase without neutral, using the armour as an earth.

Guidance advises NOT using the black as a neutral, but in any event all cores should be sleeved with the appropriate colour sleeving at terminations.

The armour must be earthed, but whether it is possible to use it as the earth for the load installation depends on the type of earthing used on the system, the cable size and the cable length.

The possibilities range from:
- use 2 core supply and the armour for the earth
- use 2 core supply, and the armour *and* third core for the earth
- use 2 core supply, earth the armour at the supply end, isolate and insulate the armour at the load end and provide a local earth at the load installation

 

[333rocky333]

Hi Guys,


On a 1.5mm 4 core armoured cable, the colours are brown, blue, black & grey.
Brown is live and blue is neutral,

Oversleeve the black and use as earth

On a 2.5mm armoured cable there are 3 wires, brown, black and grey. Which one is neutral?

oversleeve the black and use as earth
oversleeve the grey and use as neutral

 

[HERTS P&D]

Thanks for the replys guys,

On the 1.5mm wire which is being used for garden lighting, what colour should be on the grey wire to sleeve it so that it powers another set of lights?

Andy

 

[333rocky333]

Also brown normally.
Grey and Black are both colours used as Live, but normally associated with Three phase.
The armour should still be earthed in addition to using the spare cores also

 

[333rocky333]

It is not essential that you use a core as Earth, the armour would usually be sufficient if terminated correctly.
That would leave you more cores as switch lines if thats what you need

 

[HERTS P&D]

Can I buy sleeving in 1metre sections, as 100metres would be a waste and what size sleeving do I need for 6mm, 2.5mm & 1.5mm wiring?

Andy

 

[electronicsuk]

Can I buy sleeving in 1metre sections, as 100metres would be a waste and what size sleeving do I need for 6mm, 2.5mm & 1.5mm wiring?

Andy

Earth sleeving is generally available in small amounts from DIY sheds, although not sure about colours other than green/yellow. It's so cheap for even 100m that I can't imagine many people would be interested in purchasing less than that.

 

[Monkeh]

10m rolls are usually fairly easily available.

 

[timtheenchanter]

last time I looked a 1m strip from a shed cost as much as a 10m roll from my wholesaler.

Just to add CEF do it by the meter

 

[ban-all-sheds]

I hope my questions are not too stupid.

No, they aren't.

But thinking that you are anywhere near competent enough to start installing armoured cable for outdoor lighting installations and complying with the law would be.