Using armour as earth

[uksparks]

Hi,

ive been to look at a job today, used to be a pub a couple of years ago, now a house.

They have just gutted the kitchen and are going to refit.

There is s sub main (Henley blocks from head), 2 core 25mm SWA, run is approx 55 - 60 meters from head to board.

anyway, it needs a new board etc and a load of new circuits.

i just feel uneasy about using the steel wire on the SWA as the earth, I would rather have a 3 core or another separate earth.

ive not taken any readings as yet, only looked at it.

The only OCPD is the main fuse at present, I'd like a switched fuse put in.

what would you do regarding the earth? Would you use the steel?

 

[b55.v2]

then why didnt you just say that in the first place instead of posting something so brief as to be incoherent ?

 

[Deleted member 26818]

As far as I am aware, EW type glands are for use on single core armoured cables?
I think it's EEX for explosive atmospheres?

 

[davesparks]

then why didnt you just say that in the first place instead of posting something so brief as to be incoherent ?

I made the, obviously incorrect, assumption that you would already be aware of such basic information.

 

[b55.v2]

I made the, obviously incorrect, assumption that you would already be aware of such basic information.

What basic information ?

 

[andyb]

EW Stainless steel, I didn't google it. Honest.

 

[davesparks]

As far as I am aware, EW type glands are for use on single core armoured cables?
I think it's EEX for explosive atmospheres?

you'd want aluminium glands for single core as its aluminium armour.

 

[davesparks]

EW Stainless steel, I didn't google it. Honest.

Nope, they are available in brass and aluminium the same as BW and CW

 

[davesparks]

What basic information ?

The three basic types of SWA gland.

 

[andyb]

Nope, they are available in brass and aluminium the same as BW and CW

Bugger!

 

[shanky887614]

The three basic types of SWA gland.

they only mentioned bw and cw at college and the first i heard about ex etc was from on here

 

[b55.v2]

The three basic types of SWA gland.

Just because i didnt understand your previous post doesnt mean im not aware of the 3 types of swa gland.

 

[davesparks]

they only mentioned bw and cw at college and the first i heard about ex etc was from on here

Ex is a different thing entirely, which I haven't got a clue about.

But general use industrial metal (usually brass) cable glands are referenced with letters A B C E G

A, usually A1 or A2 are stuffing glands, usually brass, for unarmoured cables.
B, usually BW are armour clamping glands for SWA (or ally version for AWA)
C, usually CW are armour clamping glands with a sheath seal
E, usually EW are armour clamping glands with sheath seal and bedding seal. Also EW variants are made for steel armoured lead sheathed cables.
G, for braided screen flexible cables like SY and CY

 

[b55.v2]

EX = braided sy cable gland

 

[andyb]

I can't remember what I was taught at college. I've spent my entire working life asking for internal or external glands.
Of course, I've been vaguely aware that the pack had letters on it, I just never bothered about it.

 

[LeeH]

E1W have an extra seal in them.

Internal and external sheaths

Edit. Dave covered the lot.