Terminating SWA in a buried backbox?

[RF Lighting]

As the gland will remain accessible at the CU end, then I see no problem with your proposals.

I may have got a bit carried away with the em lights, but I'm not really used to all this domestic work

 

[ban-all-sheds]

So if I had a link between two sockets with an inaccessible JB in it that would be OK because the other ends of each piece of cable would remain accessible at the sockets?

 

[electronicsuk]

Now back to the off topic bit. I have these emergency lights on the ceiling in the hallway and at the top of the stairs:

They are only about 50mm diameter, and hardly noticeable. I have them wired so they go into maintained mode if the smoke alarms go off.

I like. Where did you get them? I assume they're a self-contained unit and not a downlight with a separate emergency conversion pack?

 

[RF Lighting]

So if I had a link between two sockets with an inaccessible JB in it that would be OK because the other ends of each piece of cable would remain accessible at the sockets?

No, because that is an entirely different situation.

It the OP's situation, he needs the armouring to be earthed to avoid the need for RCD protection.

The armouring will be earthed at the CU, and this connection will remain accessible for inspection and testing.

As the SWA is 3 core, he will not be relying on the armour to provide an earth to the accessory. The gland at the accessory is not actually required, and in the unlikely event of the joint failing, it will not affect the safety of the circuit.

I would be quite happy to bury this gland.

 

[RF Lighting]

I like. Where did you get them? I assume they're a self-contained unit and not a downlight with a separate emergency conversion pack?

It's one of these jobbies. Have a google around, and you'll probably find it cheaper. This was just the first rsult that came up for me. The place I got mine from don't seem to do them anymore.

http://www.safelincs.co.uk/Switchable-LED-Recessed-Downlighter-MRDM/?fdb=true

 

[londonboy]

So what about all the flats that are wired in pyro, glanded into the flush boxes, do none of them comply?

 

[RF Lighting]

It depends. If they used pot tails, or proper pyro boxes then it will be ok. If not, then it won't comply with current regulations.

It used to be acceptable in t'olden days to have inaccessible screwed connections.

 

[ban-all-sheds]

No, because that is an entirely different situation.

I'm not convinced.

It the OP's situation, he needs the armouring to be earthed to avoid the need for RCD protection.

In the OP's situation he needs the armour to comply with the requirements of BS 7671 for a protective conductor. Since 522.6.6 (i) doesn't specify any particular regulation(s), the armour has to comply with all of the ones which apply to cpcs.

Including 526.3.

I would be quite happy to bury this gland.

I'm sure most people would, but that doesn't mean it complies.

 

[RF Lighting]

But glanding it at one end will satisfy the regs. Where the strands of the armoured finish is where the CPC finishes.

You do not have to use the same CPC to supply the circuit as the one you use to protect your wiring from the penetration of screws etc.

If you were running a steel conduit from a metal socket box into a void below the floor, would you earth it at the socket end and the end which finishes with a female bush in the floor void or just earth it at the socket end?

 

[ban-all-sheds]

But glanding it at one end will satisfy the regs. Where the strands of the armoured finish is where the CPC finishes.

I see your point.

You do not have to use the same CPC to supply the circuit as the one you use to protect your wiring from the penetration of screws etc.

I know that - but needed or not, I was thinking that if there was a connection at the end, it would still need to be accessible.

If you were running a steel conduit from a metal socket box into a void below the floor, would you earth it at the socket end and the end which finishes with a female bush in the floor void?

No.

And I might use one of those Kopex inserts instead of a bush

 

[1john]

would you bury a coupler on a steel conduit in plaster as i see this as the same.

 

[ban-all-sheds]

I guess you shouldn't.

 

[1john]

In regards to the OP proposal, i dont like it, i dont think it complies but regualations aside i feel that it is acceptable and safe and only has to go down as a deviation.

 

[NotHimAgain]

I guess you shouldn't.

So all those installations in cast concrete structures are in breach of the regulations are they

If you have trouble accepting that this is clearly not the case - then you could apply a major UK Lighting manufacturer's defence - not named because they might decide to sue me .

This simply states that if the connection is part of - according to them meaning on or near, or just loosely associated with, equipment that complies with an 'appropriate' standard - then [526.3 (v)] applies. They used this to justify unenclosed connections on ELV down lighters, but they appear to have over looked [421.7]

Conduit should comply with BS EN 61386. Now this probably includes the socket, but does it include the male bush .

Armoured cable manufacturers recommend the use of glands for some terminations but the glands are not mentioned in the cable standards - is this the same argument? Glands could be considered to be part of the 'equipment' (see the definition of electrical equipment in BS 7671).

EDIT: Just found this

Industrial Cable Gland Specification
A new European standard for cable glands, EN 50262, was published on
March 1st 1999. As a result, the current BS 6121 series of British Standards
for cable glands was withdrawn.
It is important to understand that there has been a change in the basic
methodology. The existing BS 6121, a physical dimensional standard,
ensures a single and relatively high level of performance.
EN50252 provides a design framework that ensures a product meets the
minimum requirements for safety. The most basic products designed to meet
EN50262 may fall short of meeting the users requirements.
Manufacturers will provide more information than before, but the user must
now make more decisions regarding the suitability of the product for the
application.

I will try and get these standards - they might add something.

 

[ban-all-sheds]

So all those installations in cast concrete structures are in breach of the regulations are they

They would appear not to comply with 526.3.

according to them meaning on or near, or just loosely associated with, equipment that complies with an 'appropriate' standard - then [526.3 (v)] applies.

It's not unknown for manufacturers to claim that the regulations actually mean something favourable to their product.