Should I use 1mm or 1.5mm earth in domestic lighthing?

[midiman]

Hi,

I need to earth a replacement faceplate to a steel back box in the wall.

Should I use a 1mm, or 1.5mm sleeved cable for the job?

Thanks

 

[KEV 1 N]

Either will be fine as long as it's green/yellow wiring or sleeved that colour.

 

[midiman]

Either will be fine as long as it's green/yellow wiring or sleeved that colour.

I will go out and buy a metre of 2.5mm t&c and sleeve it yellow and green.

I just want to be safe.

Thanks

 

[westward10]

Wait for it.......

 

[KEV 1 N]

The earth in the 2.5 is actually 1.5, but 1.5 will be better than 1mm. If you use 2.5mm that may be too big to fit in the switch earth terminal

 

[midiman]

The earth in the 2.5 is actually 1.5, but 1.5 will be better than 1mm. If you use 2.5mm that may be too big to fit in the switch earth terminal

Hi,

Sorry I didn't explain it well.

I meant I will go out and purchase a metre of 2.5mm T&C so that I get the 1.5mm earth.

Thanks.

 

[The Ghost]

I just want to be safe.

Seems you might be safer leaving it alone.

 

[saint]

If your spleen ruptures and needs removing would you pick up a knife or a spoon from your local shop to remove it?

 

[The Ghost]

Wow I got a dumb from a dumber.

 

[telectrix]

I will go out and buy a metre of 2.5mm t&c and sleeve it yellow and green.

I just want to be safe.

Thanks

just use this and put green stripes on it.

 

[westward10]

What sort of accessory is it.

 

[telectrix]

What sort of accessory is it.

a metal one.

 

[einstein]

please strip the cable correctly using an electricians knife, dont just pull the earth to split the grey sheathing

 

[PEG]

please strip the cable correctly using an electricians knife, dont just pull the earth to split the grey sheathing[/QUOTE]
...Or you'll be no better than 65% of all the sparks i've ever met

 

[stevethesparks]

please strip the cable correctly using an electricians knife, dont just pull the earth to split the grey sheathing

I thought it was a copper rip cord - what else could it be used for

 

[Pete999]

Hi,

I need to earth a replacement faceplate to a steel back box in the wall.

Should I use a 1mm, or 1.5mm sleeved cable for the job?

Thanks

What size are the lighting circuit conductors L,N and cpc? written yesterday and forgot to post

 

[Cadgey123]

please strip the cable correctly using an electricians knife, dont just pull the earth to split the grey sheathing

Please don’t tell me we are still reverting to the “ your going to stress the copper conductor, therefor decreases CSA, therefore an immediate fire risk.”
I strip it like that, not one of my jobs has ever went wrong

 

[The Ghost]

ever went wrong

These little touches are the difference between an electrician and craftsman.

 

[Cadgey123]

These little touches are the difference between an electrician and craftsman.

I am going to disagree.
I still cut a neat edge with my knife at the end of the cable.

If you connect 10 sockets on a RFC and connected them both ways. I bet the resistance of the cpc ring is the same. A lot of rubbish. My college didn’t even bother telling us otherwise.

 

[Risteard]

My college didn’t even bother telling us otherwise.

To be really controversial the training centre here taught to strip it by pulling the cpc! I really don't see the problem with it.

 

[Cadgey123]

I don’t see a problem with doing it with a knife. I just think it’s a faff and more risk of catching the cables. Trying to get your knife in a small accessory box is a pain.

 

[HandySparks]

Trying to get your knife in a small accessory box is a pain.

Try a smaller knife. These are really solid, unlike the plastic ones.
https://www.amazon.co.uk/Stanley-9MM-Snap-Blade-Knife/dp/B0001IW5A4

 

[Pete999]

I don’t see a problem with doing it with a knife. I just think it’s a faff and more risk of catching the cables. Trying to get your knife in a small accessory box is a pain.

Never s

Try a smaller knife. These are really solid, unlike the plastic ones.
https://www.amazon.co.uk/Stanley-9MM-Snap-Blade-Knife/dp/B0001IW5A4

Don't think you would go wrong with a knife like this
https://www.amazon.co.uk/goods4less...7896736&sr=8-3&keywords=ck+electricians+knife

 

[Strima]

Never s

Don't think you would go wrong with a knife like this
https://www.amazon.co.uk/goods4less...7896736&sr=8-3&keywords=ck+electricians+knife

That's all I use, as long as they're kept sharp they are a good knife.

I don't like Stanley knives or similar as the blade is very brittle and can snap off easily into little sharp shards...

 

[The Ghost]

When I look at a job and see split ends on cables and screws not straight in the fixings I think straight away "Ok not a top job here I wonder what other corners have been cut". I showed this to a third year trainee and like you @Cadgey123 he said it's a load of rubbish, not quite the same words but similar. I challenged him to strip ends of cables faster than me. He hadn't even got hold of the earth and I had stripped my cable ends. I know its a bit purist but that is my whole approach to be exact as I can. I just like to make everything neat and be very careful. I know I probably would get thrown off site if found to be doing such careful work but hey I am my own man I can proced pretty well how I like. Conversely if you inspect work that has been done the way I would suggest, you think Aha one of those guys, very fussy and careful ok...

 

[westward10]

Nothing else happening, obviously.

 

[Midwest]

please strip the cable correctly using an electricians knife, dont just pull the earth to split the grey sheathing

Okay, need to change the habit of a life time.

 

[Pete999]

View attachment 38801

Okay, need to change the habit of a life time.

Might change your mind if you were taught correctly in the first place Middy.

 

[telectrix]

hmmm.i might have banged my fist on the wall when cpc has snapped when using it as a ripping cord, but never had a sliced finger or a cut through the conductor's insulation.

 

[ipf]

I don’t see a problem with doing it with a knife. I just think it’s a faff and more risk of catching the cables. Trying to get your knife in a small accessory box is a pain.

Practice and craftsmanship, maybe?

 

[telectrix]

what we need is as was developed by star trek .dr.mccoy .laser probe cuts through skin but not tissue ( insulation) and conductor ( bones )

 

[PEG]

Vortigen is correct,and then you just have to step back,and let each to their own.

I have,and would never,run a knife around the sheath of a SWA,because the tiny cut to the plated steel armouring,is where the corrosion starts...simple as that.

I would not unduly apply scorn,to a man using a knife to do the same task,it's just that he's wrong...and i'm not

 

[The Ghost]

Just as a matter of interest @PEG how do you strip the outer sheath of SWA without the aid of a sharp implement?

 

[Midwest]

Might change your mind if you were taught correctly in the first place Middy.

I think I was taught rightly or wrongly, of both ways. Never seemed an issue to me not to use a knife.

 

[NDG Elecs]

I can categorically state that using the CPC as a rip cord does decrease the CSA. Recently I had a small ring with L-L and N-N each measuring 0.10 ohms. Due to my poor de-sheathing technique the CPC when tested was 0.169 ohms. The 0.002 ohm shortfall posed a very real fire risk in my view so I immediately pulled the walls apart and rewired it all. It's a shame really as the plasterer and decorator had only been in the week before..

 

[PEG]

Just as a matter of interest @PEG how do you strip the outer sheath of SWA without the aid of a sharp implement?

I have always used either a Klauke or Thomas Betts scoring tool,which whips round the periphery of a circular sheath,with an adjustable depth,swivelling cutter. A couple of spins,and then pull off the end,results in the sheath coming off like an onion skin.

Same tool will do many sizes,and flexible cables,spring loaded design,blade can be replaced,although i never have,just dressed up with a DMT hone.

If i was demonstrating the benefit of such a tool to students,i would get them all to strip 6" of the sheath,on a 12" piece of SWA,using standard knifes,etc.

I would then strip 3" off the other end,using my favoured weapon. Both ends can then be coated in a weak acid solution,to speed up simulated corrosion,and left for a week or so.

When the remaining sheath is removed,it is obvious,which process is the most beneficial.

....Or,i could just accept the frequent advice,regarding getting either "out more" or "a life"

 

[telectrix]

with SWA, i use the CK armourslice. first to score the armour prior to breaking off, then approx. 1" back to cut the outer sheath. all done in one operation.