Interconnected Smoke Alarms - Mains Powered

[a1topdog]

When connecting the above I need to use 3 core and earth 1mm cable.
I have bought the new colour cable (Black/Brown/Grey) - the question is
what colour should I use for:

1) Live
2) Neutral

Thanks.

 

[andy]

When connecting the above I need to use 3 core and earth 1mm cable.
I have bought the new colour cable (Black/Brown/Grey) - the question is
what colour should I use for:

1) Live
2) Neutral

Thanks.

i usually use brown for live, black for neutral (you should tape this blue so you can see its neutral) and grey for IC

 

[a1topdog]

Thanks -

 

[plugwash]

most sane sparks i have talked to think its most sensible to use black as neutral

however the niceic in their infinite wisdom decided to reccomend use of grey as neutral (apparently to try and break the connection in peoples minds between black and neutral)

which one you go with is up to you but whichever you do make sure you clearly mark the neutral core in blue at the terminations.

 

[a1topdog]

Assuming I use the black as the neutral , when I run the feed from the CU would it be frowned upon if I used the same 3 core (I've a big roll of it!!!) and snipped the grey at the CU and first alarm?

 

[andy]

Assuming I use the black as the neutral , when I run the feed from the CU would it be frowned upon if I used the same 3 core (I've a big roll of it!!!) and snipped the grey at the CU and first alarm?

get rid of the grey by putting it in a terminal block. dont get rid of it all together and make sure that the black os marked blue to avoid confusion. most sparks will assume you have used grey as IC and black as neutral. altho, as already mentioned, NICEIC want you to use another colour

 

[Lectrician]

I would go the NIC route, thats my job.

Using 3 core to the CU is fine, but DONT snip the extra core - terminate it both ends with a terminal block.

It is sometimes easier to run a 3 core from the CU to one detector, and another from the same CU to the other detector. Join the blacks (or greys) with a through crimp or terminal block, and put both browns in the MCB, and both neutrals in the neutral. Can save cable and hastle on some installs this way.

 

[fireman22]

NIC also state that you should never snip out a core you are not using, sleeve as earth instead

 

[Lectrician]

Just putting it in a terminal is fine - only needs to be earthed down in hazardous areas such as petrol stations.

 

[fireman22]

fair comment, but new snags book on earthing show unused cores earthed. no mention of risk area though.

 

[securespark]

It does indeed!

 

[Lectrician]

Never earthed any of mine down! Snags and solutions - huh!

 

[a1topdog]

Thanks for all the advice , much appreciated.

 

[securespark]

Never earthed any of mine down! Snags and solutions - huh!

Lec

Does this partly confirm my fears that the NIC make it up as they go along??!!

 

[Lectrician]

Umm....

I don't think the NIC would pick you up on something like that on an inspection, but are recommending it.