SWA glanded in a plastic stuffing gland

Yes, but how do these  protect electricians from simultaneous contact? You can still get at the brass armour termination inside the enclosure.

Have you come across the SWA storm glands? rated IP68, Plus, there’s no need for a shroud, It works with various cable types, including armoured, non-armoured, SY, and CY braided cables. It’s non-corrosive and UV stabilised and zero-halogen.Each pack comes with EarthingNuts

OlympusMons said:

Hi Graham, do you mean an armour strand when you say tail?

Possibly, but this will be quite difficult to achieve. Somehow, the armour needs to be terminated in a suitable gland, and from this a copper conductor 'tail' can be brought out for testing.

My preferred method would be traditional SWA brass gland into 'gapping tube', with tail brought from the brass gland, and some suitable insulation or barrier(e.g. cold-shrink sleeving) over the gland.

gkenyon said:

if something available for testing is needed, provision of an insulated tail to a suitable 4 mm shrouded test terminal (all insulated), and suitable labelling, would be a better approach ...

Hi Graham, do you mean an armour strand when you say tail?

I am thinking that the PVC bedding surrounds each strand so that none of the strands are touching the ones next to it.

So taking a continuity reading between the source and your test point would give a much higher reading than you would get from if the strands were made off into for example a brass gland and the reading was taken from there. Or if the likes of a jubilee clip were used, along with plastic glands.

AJJewsbury said:

Careful... same issue could arise during the process of connecting a bond to an extraneous-conductive-part or the cable to the MET or or the MET to the DNO's earth terminal - and we don't insulate any of those....

Careful indeed. Suitable protective clothing ought to be worn, particularly with the risk of either diverted neutral currents or (and I wouldn't recommend doing it when he installation is energised, but to illustrate) protective conductors currents.

We are not, however, talking about connecting or removing bonding, but something else ...

However, a consideration is also that we need to protect electricians going about their work. A brass gland won't do this, unless insulation (or some other form or barrier or enclosure) is used.

Careful... same issue could arise during the process of connecting a bond to an extraneous-conductive-part or the cable to the MET or or the MET to the DNO's earth terminal - and we don't insulate any of those....

   - Andy.

AJJewsbury said:

But where does it say that earthed parts of a different earthing system need to be covered with basic insulation?

It doesn't. However, BS 7671 requires that simulatenously accessible exposed-conductive-parts are connected to the same earthing system.

A permanent barrier (or enclosure) ... perhaps insulation ... could be used to prevent simultaneous contact, depending on the circumstances.

However, a consideration is also that we need to protect electricians going about their work. A brass gland won't do this, unless insulation (or some other form or barrier or enclosure) is used.

all true - the problem is that the CPC from the wrong zone is not just a CPC, but a part introducing a potential. But if it needs basic insulation, maybe argued.

Now there are not enough accidents to worry about really but in principle there is a risk - its why we do put insulation on the  neutral which is also at the 'wrong' earthy potential.

M.

A correctly sized plastic bodied gland is preferable.

I don't disagree at all ... (as per my earlier posts) but in terms of what the regs actually require...

The shroud/boot can be removed 'without destruction' and is therefore not suitable for basic protection (Regulation 416.1).

But where does it say that earthed parts of a different earthing system need to be covered with basic insulation? If we go down that route the sheath covering the armour isn't rated for insulation at all, so the problem then gets a lot bigger than just the gland. I thought we only needed to prevent things being simultaneously accessible - if it's covered it's not accessible. A properly fitted shroud shouldn't be easily removable, but I might suggest a cable tie around the cable to prevent it slipping to make sure. If you're wanting to make it foolproof then you'd need a way of stopping people running an extension lead from the other zone...

  - Andy.

Agree, the boot can easily be removed, A correctly sized plastic bodied gland is preferable.

M