SWA sheath used as main Earth

[Bonse]

Hi guys

I recently installed a submain and fed it with 16mm 2 core SWA XLPE and used the sheath as an earth....

does anyone know the calculation to work out the equivalent conductor size ? i know it works out to be approx 35mm.

Hope that question makes sense.

Darren

 

[mattmoo1974]

Bonse iv got a PDF of SWA CPC values in box me your email addy and i ll send it to you
The equation is on there as well.

 

[RWJ]

This PDF is a great guide

http://www.electriciansforums.net/a...6730996-can-we-use-armour-swa-cpc-swa-csa.pdf

it was originally posted by Lenny
http://www.electriciansforums.net/e...ulations/23288-can-we-use-armour-swa-cpc.html

 

[IQ Electrical]

I answered your original post here http://www.electriciansforums.net/e...-swam-sheath-earth.html?highlight=#post316078

Why ask again?

 

[ian.settle1]

I answered your original post here http://www.electriciansforums.net/e...-swam-sheath-earth.html?highlight=#post316078

Why ask again?

Probably can't find his original post:freak:

 

[PC Electrics]

Interesting notion; using the sheath for the cpc! Hhmm, isn't the sheath pvc?:smartass2:

 

[IQ Electrical]

Interesting notion; using the sheath for the cpc! Hhmm, isn't the sheath pvc?:smartass2:

Damn, I've got some remedials to do now!!

 

[Engineer54]

This link is a paper written by John Peckham, a well respected Chartered Engineer. It will give you a very good basic understanding on the subject.
The tables for both thermoplastic and thermosetting SWA cables will give more realistic results, without the need for any further calculations, that may be required by the other table posted here earlier....

I have personally been using these 2 tables for almost 4 years now, they are good to go... lol!!!

http://www.electriciansforums.net/a...an-we-use-armour-swa-cpc-using-armour-swa.pdf

 

[Deleted member 26818]

I believe John has updated the tables for the 17th.
Been using them myself for a few years as well, much clearer and easier to use to my mind.

 

[Knobhead]

I don’t know if it’s still possible but at one time you could specify high conductivity armour. One armour in say 4 or 5 would be copper. We used these a lot under M&Q regs. The copper would be just a tad bigger that the steel as it would flatten down in the gland. You would only get them if you went over 120mm cable.
I’ll say I’ve never run a separate CPC with a cable but with one proviso, on many large cable trays within a switch room I would run a 1x1/8” copper tape bolted all along the tray, this could be joined on to for any cable or enclosure.

One switch room I modified had two incoming feeds, one @550V via a 0.3” 3c PILCSWA, the other @440V via a 195mm 3+1/2c SWA (high conductivity) both boards shared the same main cable tray, so both linked via the earth tape. I never worried about earth paths in there.

 

[Bonse]

I answered your original post here http://www.electriciansforums.net/e...-swam-sheath-earth.html?highlight=#post316078

Why ask again?

Was on my phone the other day and it seemed to crash. then i couldnt find it so i reposted it.

cheers

 

[Bonse]

Thanks everyone for the replies. ive only just managed to get back to my computer! will have to sort that damn phone out lol

 

[Engineer54]

I believe John has updated the tables for the 17th.
Been using them myself for a few years as well, much clearer and easier to use to my mind.

Spin,

Do you have a copy of the updated tables, if so can you post them here??

 

[Deleted member 26818]

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