Swa armour earthing

[brizospark]

Does the steel wire armour have to be earthed in ALL cases?

 

[big bang1]

yes all conductive mechanical protection has to be earthed and if possible at both ends, although i have fit some swa's into so small plastic enclosuers it's impossible.

 

[brizospark]

Also should SWA earth tags be fitted in ALL cases?

 

[SirKit Breaker]

Also should SWA earth tags be fitted in ALL cases?

Yes. And they should be terminated to the earthing bar.

Cheers........Howard

 

[brizospark]

what if for instance there is a cpc in the SWA, at the DB end earth tag with fly lead connected to earth terminal. Other end metal socket. Is it a reportable fault if no SWA earth tag at this end?

 

[Deleted member 26818]

No.
If for instance, you were keeping a PME earth separate from a TT earth, then the tag would only be used at the earthed end.
There are also 'earth nuts' which have a means to attach a fly lead.
It has often been argued that if the enclosure is metal, and any insulating paint/coating has been removed, then the tag and fly lead can be ommited.
However if the manufacturer's instructions stipulate the use of the tag and fly lead, then it should be used.

 

[SirKit Breaker]

what if for instance there is a cpc in the SWA, at the DB end earth tag with fly lead connected to earth terminal. Other end metal socket. Is it a reportable fault if no SWA earth tag at this end?

I would report the fault and make arrangements to fix it at some convenient time. It is a departure from BS7671, but dont ask me the reg number.

Just read spins post, he knows more about it than me so go with his suggestions.

 

[brizospark]

yes i have used the earth nuts they are pretty good ,

But doing a PIR I noticed that on ring circuits run in SWA there are tags at the db ends but not at the sockets was not sure if its a fault

 

[johnboy6083]

just to add, a banjo can be ommited if a threaded entry is used, and also if a serrated washer is used. there is no difference to earthing of SWA, than there is earthing conduit or MICC. i agree, that if glanding to a bare gland plate or trunking, then there isnt any need to use a banjo. you would have to ensure the locknut was very tight. this is my opinion.

 

[brizospark]

it would however be good practice to employ earth tags in all cases where possible though?

 

[johnboy6083]

yes of course. i always use them, unless on big jobs, and told not to. i wouldnt code them on a PIR, unless i thought that the contact betwwen the gland and the earthing terminal of the board wasnt good enough.

 

[brizospark]

sometimes metal clad sockets have a kind of laminate coating over them though dont they

 

[johnboy6083]

yes, but the locknut, or bush in the case of conduit, still provides good contact, providing its tight!

 

[telectrix]

if you use earthing nuts, they cut through the paint/coating .

 

[Deleted member 26818]

At the end of the day, it boils down to what you consider to be safe or unsafe.
It can be argued that using the glands without banjos is no different to using brass bushes with conduit.
Although it can also be argued that the manufacturer's advise fitting them, and that SWA is flexible, so the glands are more likely to come loose.