Connections to adaptable box.

[endecotp]

I have a 6”x6” adaptable box that currently has only steel conduit connections to it. I need to add T&E. What’s the right way to do that?

In particular, what’s the “right way” to terminate the new cable’s earth? The box doesn’t have an earth terminal.

Also, what are the requirements for strain relief? Am I required to use a gland?

Finally, are there any connectors that I can use inside the box that are considered maintenance-free?

I’m aware of various possibilities but I’d love to hear what the best practice is. Thanks.

 

[Murdochcat]

Is the steel conduit earthed anywhere else ?

 

[Robin0577]

Traditionally a bonding nipple https://www.tlc-direct.co.uk/Products/CO20BNIP.html

These days more likely a shaped compression gland designed for T&E https://www.tlc-direct.co.uk/Products/WKP20F254.html

CPC termination would usually be by means of a brass bolt, nut and washer with a ring crimp terminal. Although most crimps don't work well with solid core cables, so a short tail of flexible core to a terminal block or Wago might be better.

 

[endecotp]

Is the steel conduit earthed anywhere else ?

Yes, most circuits are run entirely in steel conduit and it is the principle earth.

 

[Murdochcat]

Yes, most circuits are run entirely in steel conduit and it is the principle earth.

You have lost me.

Where is the twin and earth running from and to?

 

[endecotp]

You have lost me.

Sorry about that.

Where is the twin and earth running from and to?

From this box to a new socket.

 

[flameport]

Surely installing the circuit to the new socket in the same steel conduit as used for the rest of the installation would be the proper solution?

 

[endecotp]

Surely installing the circuit to the new socket in the same steel conduit as used for the rest of the installation would be the proper solution?

It could be a possibility but is not one I’ve seriously considered, for practical reasons.

 

[endecotp]

CPC termination would usually be by means of a brass bolt, nut and washer with a ring crimp terminal.

No-one has mentioned banjos or pirhanas yet.

Can either of those be used with a plastic gland? I guess not. Metal glands for flat cable do seem to exist but may be rare. How would that compare with drilling a hole for a ring crimp?

 

[pete01]

You can get stuffing glands made for T&E

You don't need to earth plastic

 

[morqthana]

No-one has mentioned banjos or pirhanas yet.

Nor has anybody asked where/what sort of place this is with an entire wiring system in steel conduit.

 

[endecotp]

Here’s what I’ve done; metal gland and a piranha nut:

 

[securespark]

No-one has mentioned banjos or pirhanas yet.

Incredible.

Are you telling me that Piranhas can play the banjo these days?

 

[plugwash]

Can either of those be used with a plastic gland?

I wouldn't want to rely on the clamping power of a plastic thread to maintain a secure electrical connection.