repairing a nicked conductor

[jpadie]

hello all

 

annoyingly, after a morning of struggle with getting a long length of 16mm2 three core SWA into a junction box, just at the end in despair I used some grips to help bend a conductor and this removed some of the insulation.  Is there an approved way of repairing this (tape or heatshrink) or so I need to splice and mechanically join a new length?  

 

second question is whether these conductors need earth and neutral sleeving in the CU and in the junction box (existing CU at one end, new remote CU at the other)?  

 

thanks

Justin

[markc]

This is one of those what should you do? What would you do questions.

Good few wraps of insulting (insulating) tape and you will be ok. 
As you are using a core for earth then yes tape or sleeve to identify.

[garrymartin]

Heatshrink would be preferred assuming the conductor itself is not damaged. Good-quality PVC tape at a push. 

https://engx.theiet.org/f/wiring-and-regulations/24396/repairing-insulation

 

You do need to sleeve the conductors with the correct colour sleeving for their function.

[jpadie]

thanks both.  

conductor is not damaged - i've had trouble with tape staying on for more than a year in the past.  somehow the adhesive seems to age and then the slightest bump knocks it off or loosens it.  maybe the quality of the tape I tend to use?  

 

grey core for earth and the black for neutral.  I will sleeve both in the CUs.  do they need sleeving in the junction box too for reg-compliance? 

 

 

[garrymartin]

Hence the "good-quality" comment 😉 I use 3M insulation tapes and have never had an issue.

 

Is it a junction box? It doesn't look like you are making any connections in the photo; it appears to be a pass-through of the conductors only. If it is a pass-through, then not required to sleeve them but nothing to stop you from doing it if you so wish.

[OwenF]

There is a view towards ‘de-neutralising’ black I.e. making black = earth and grey = neutral.

 

I don’t think it’s in the regs anywhere but probably one of those things people pick up as though it were.

[ProDave]

16 minutes ago, OwenF said:

There is a view towards ‘de-neutralising’ black I.e. making black = earth and grey = neutral.

 

I don’t think it’s in the regs anywhere but probably one of those things people pick up as though it were.

That has been a chip on my shoulder for some time.   In the "old" days people were happy to use blue (a phase colour) as neutral so why so against black now?

 

Of course my gripe is why is only brown / black / grey available?  *  particularly when talking of 3 core and earth flat cable, Name me one case where you will actually use 3 core & earth as a 3 phase cable?  Brown / Blue / grey would seem a better choice.

 

* Yes I know we are talking about SWA here, where 3 phase e.g to feed a motor is a real possiblility, and where you CAN buy 3 core in brown / blue / green-yellow

[Jenki]

2 hours ago, ProDave said:

That has been a chip on my shoulder for some time.   In the "old" days people were happy to use blue (a phase colour) as neutral so why so against black now?

 

 

Brown, black, grey for me is Live, Neutral, Switch live for say Smoke alarms or

Live, Live, strapper for 2 and x way switches.  My brain sees black and still  thinks Neutral/live, so for SWA the same applies. Brown = Live, Black=Neutral, Grey=CPC  all sleeved accordingly..I'm not changing 😄

[FuerteStu]

As a commercial/industrial spark who spends most of his days working on armoured.. Sleeving (identifying) the cores is just part of the job. 

 

Many multi core (more than 5) armoured cables are white core only and numbered. 

 

It's always grey (blue sleeved) used for neutral. The phrase 'deneutralise the black'. Was just a way of making people remember. Modern apprentices just say "black is cpc, just like the armour". 

 

Heat shrink the damage, live and learn. 

If you need to bend the cores in future, use the handles if the pliers, not the metal ends.