Split Concentric Termination

[catdog]

I'm no expert on split concentric (assuming that's what this is)......But an earth clamp doesn't seem the best solution to this (also as the earth cores appear to be insulated!

This is for an eicr on a sub main but I'll have to do the remedial work at some stage.

Any advice on how to terminate this correctly?

Thanks!

 

[westward10]

That is concentric but not sure that clamp serves any purpose unless the insulation below it has been removed.

 

[catdog]

Nope doesn't look like it has been! I was just doing an initial check today but the sockets this isolator supplies are earthed buy must be via another means!!

 

[Flanders]

That looks like the neutral part of the concentric cable exposed , sorry never terminated that my self but i agree with you thats certainly not the way to terminate any CPC

 

[westward10]

If that is split concentric which it probably is the outer neutral conductors should not be connected to earth, assuming this is the consumers installation.

 

[westward10]

If you have no slack on the cable you have a problem as those neutral conductors should be correctly enclosed.

 

[catdog]

Is there a gland specifically for split concentric then?

 

[westward10]

Is there a gland specifically for split concentric then?

No you can either not gland provided it is correctly supported or put a stuffing gland in place. It is no different to terminating a standard cable but the cores have a different configuration. Have you not looked inside the switch-fuse.

 

[Flanders]

Have you looked inside the switch normaly all the black are terminated into the neutral and the greens terminated into the earth , just wondering how the earth is terminated inside
Edit just seen westwards post , he beet me to it

 

[DPG]

Photo of inside please.

 

[catdog]

Haven't looked inside yet! This was one of many issues found when fiing out paper work and before removing any covers! When I get back to it I'll send a pic of inside (partly don't want to open it!)

Thanks for reponses

 

[MJPD29]

That looks like the neutral it looks like you can see part of the damaged black insulation on the top

 

[SparkySy]

Last time I saw a bodge like that I had to do this to re enclose the conductors and terminate safely, It was tight to say the least!

 

[netblindpaul]

The current version of BS951 prohibits the use of such a clamp in this manner.
If the cable is buried then unless it has suitable additional mechanical protection then it is not in accordance with BS7671.

 

[Deleted member 26818]

Not aware of any requirement in BS7671 to provide mechanical protection to cables buried in the ground?

 

[Richard Burns]

Not aware of any requirement in BS7671 to provide mechanical protection to cables buried in the ground?

NBP is presumably referring to 522.8.10 where cables without an incorporated, cpc suitable, earthed covering should be protected against mechanical damage by a conduit or duct.
Even though the regulation is worded with reverse emphasis.

 

[Deleted member 26818]

Concentric and split concentric cables have an earthed armour or metal sheath suitable for use as a protective conductor.

 

[Ian1981]

Concentric and split concentric cables have an earthed armour or metal sheath suitable for use as a protective conductor.

The earthed cores to split concentric Doesn’t fully encase and cover the whole cable tho

 

[SparkySy]

I agree, concentric is live centre conductor and pen outside conductor. Split concentric is live centre and split outer earth and neutral separate, not seen it with swa but that's not to say it doesn't exist!

 

[westward10]

Originally concentric cables were deemed okay in walls without additional rcd protection but this was later removed.