Terminating SWA at plastic Comsumer Unit

[johnston1991]

hi all,

just a quick one please probaly sounds daft but.. what are the preffered ways to terminate SWA at a plastic consumer unit? ?:| metal clad box then tails up to it ? the SWA is 2 core and im using the armour as earth for the sub main and TT'ing the second consumer unit.

cheers

 

[Andy™]

depends on CU... some can take a SWA, some cant (mostly IP rated that can). if you can terminate into it, use a metal box below and take cores straight through into CU

 

[batty]

When I do garage/sheds I usually use a volex five way Rcd protected consumer unit. I tend to use 10mm two core swa as this is adequate for most needs. I cut armour back with swa stripper and then put swa through

25mm nylon gland. I then TT building. I find you can get a 25mm large nylon gland straight into a volex consumer unit. It maybe possible with other makes but I have done a lot with volex with no problems. I used to get them from bdc but have had to find a different supply. Screwfix do a 5 way main switch one which you could then change switch for RCD as they do a 80a 30mA RCD.

I have also used MK consumer units in the past as these can take a 25mm gland but are a slightly dearer option.

Batty

 

[Evans Electric]

Oh Batty , why can't you get them from BDC anymore ? ; );\ ; \

 

[Andy™]

Oh Batty , why can't you get them from BDC anymore ? ; );\ ; \

not sure. i think we need a BDC thread to find out why

 

[M107]

I have on occasion terminated swa into insulated cu's, MK / Wylex & Crabtree ranges.

Use these to make life easier http://www.tlc-direct.co.uk/Main_Index/Earthing_Index/Piranhna_Earth_Nuts/index.html

The other option is as you say terminate into adaptable box below or next to cu the run cores straight into cu.

If I'm TT'ing a submain from a pme supply I use insulated adaptable box.

 

[DonkeyDong]

Either SWA gland straight into the plastic CU (if its a decent one) or plastic/steel adapta box.

D.

 

[johnston1991]

thanks for all the replys should be a lot of help whn i coem to use it, the consumer unit is just a cheap mk sentry 6 way board from screwfix so may be a bit iffy shall wait and see

thanks

 

[Riggy]

Has anyone started a BDC thread yet?

 

[Apache]

Has anyone started a BDC thread yet?

behave!

 

[Evans Electric]

Why is everyone talking about BDC all of a sudden , What can it mean ?

 

[0151]

use a 3 core armoured as the swa only requires earthing at one end and use a stuff in gland on the plastic cu............not my method just an idea as i prefer to use split con cable as its a lot easier

 

[SPECIAL LOCATION]

Oh Batty , why can't you get them from BDC anymore ? ; );\ ; \

hmmmm?

did they go into administration Deke??/:O] ; \

 

[SPECIAL LOCATION]

Why is everyone talking about BDC all of a sudden , What can it mean ?

perhaps the rumours are true people are buying from them again??Blushing

 

[Voltimax]

use a 3 core armoured as the swa only requires earthing at one end and use a stuff in gland on the plastic cu............not my method just an idea as i prefer to use split con cable as its a lot easier

Here's a question on split concentric cable since it's been mentioned.

For those that use it, you will undoubtedly know what the British Standard number is. Can you tell me if it is one that BS7671 refers to as a recognizable cable? My reason for asking is that I have been informed it doesn't and that is to only be used by distributors. Where do you find the tables for volt drop, technical data etc?

I know that NAPITs view is it is not to be used.

Thoughts?

 

[Evans Electric]

There may be a mix-up here . A split concentric cable has a single inner core (Live) The concentric cores are copper , half of them were insulated in black PVC the other half insulated in green. No need for a gland. AFAIK we were allowed to use them.

A concentric cable ,as used by the distributors, has all the concentric wires uninsulated, they use it for PME and merely split it at the cut-out. You can't use it on installations.

I have worked on installations which where TNC throughout the project. This was done using single core bare pyro (MICC) with earth tail pots. Its done to save money I believe, this was a huge project, but as I remember, Home Office approval is required.

To connect a socket , centre core was live, the earth tail looped , continuous, to the back box ,the neutral and the earth.

The metal dist. bds. had no neutral bar, just an earth bar bolted to the case.

 

[Andy™]

make it TNC and use pyro to save money??? could do it cheaper with T&E and normal earthing!

 

[kme]

I wouldn`t be happy terminating swa into a stuffing gland, TBH. As for the concentric debate, I didn`t think it was recognised by 7671 for installations - though I`m not certain, which is why I didn`t post.

Clarification ( with reg) would be appreciated?

 

[0151]

Fixed Wiring and Mains Cables - SPLIT CONCENTRIC - Plain annealed stranded copper phase conductor, XLPE insulated surrounded by a concentric layer of plain annealed solid copper neutral conductors. XLPE insulated and plain annealed solid strand bare copper earth conductors, PVC outer sheath. Black. 600/1000 volts grade to BS7870

heres the links

http://www.clevelandcable.com/products.asp?id=2271&step=2&catid=20

http://www.batt.co.uk/products/view/610/Split-Concentric-Cable-BS7870

ive been installing it for over 8 years as sub-mains and street lighting both the napit and niceic local engineers are happy with it during their annual inspections

 

[Andy™]

I wouldn`t be happy terminating swa into a stuffing gland, TBH. As for the concentric debate, I didn`t think it was recognised by 7671 for installations - though I`m not certain, which is why I didn`t post. Clarification ( with reg) would be appreciated?

SWA into stuffing gland does sound a bad idea - if anything, at least a gland on the end of the armour.

split con has been used for many years - ive used it myself for submains etc - much easier to terminate and work with than SWA