Permanent live for smoke alarms and emergency lighting

[Neptune]

Need some guidance please.
I know that smoke alarms require a permanent live and neutral in order to operate. Is this also the case with emergency lights? (The type you have in stairways)

Secondly, have I also understood correctly that these two can only be available at the ceiling rose if the loop has taken place in the ceiling? I.e. if the loop is at the switch, I will have a neutral at the ceiling but not a permanent live?

Thanks in advance.

 

[Neptune]

on new work, you would generally use a 3 core/E cable from light to switch in order to provide a N at switch.

Where on the switch would this new Neutral wire connect?
Also, can I please confirm that you are proposing a 3 core and earth cable from the light to the switch under this configuration.

 

[BiddeldyBwah]

Where on the switch would this new Neutral wire connect?

It wouldn't normally, you'd put it in a connector block unless you were using a newer switch that has a provision for a neutral link on the actual light switch fitting.

Also, can I please confirm that you are proposing a 3 core and earth cable from the light to the switch under this configuration.

Personally i don't understand the comment about 3 core for an N at the switch, you can just do that with T+E. T+E feed in, T+E out to light, CPC N and SL all present.

Unless you want to use 3 core to put the perma live from switch to rose in order to loop in from the rose to the next light. Sure Telectrix will clarify (i am only a meagre apprentice at present.) EDIT: I get what he's saying now, i was thinking about it from a 'take from the switch' perspective not taking the feed to the rose.

That said, i would just get an electrician out to have a look. No point guess working it when you can just pay an expert to sort out the plan in about 10 minutes.

 

[Neptune]

It wouldn't normally, you'd put it in a connector block unless you were using a newer switch that has a provision for a neutral link on the actual light switch fitting.



Personally i don't understand the comment about 3 core for an N at the switch, you can just do that with T+E. T+E feed in, T+E out to light, CPC N and SL all present.

Unless you want to use 3 core to put the perma live from switch to rose in order to loop in from the rose to the next light. Sure Telectrix will clarify (i am only a meagre apprentice at present.) EDIT: I get what he's saying now, i was thinking about it from a 'take from the switch' perspective not taking the feed to the rose.

That said, i would just get an electrician out to have a look. No point guess working it when you can just pay an expert to sort out the plan in about 10 minutes.

Are we in agreement that a 3 core and earth cable would be required for this approach (from light to switch) and the neutral wire would be terminated in a wago behind the switch - in anticipation of smart switch, etc.

 

[BiddeldyBwah]

Are we in agreement that a 3 core and earth cable would be required for this approach (from light to switch) and the neutral wire would be terminated in a wago behind the switch - in anticipation of smart switch, etc.

If you mean taking the feed to the light fitting and needing a neutral at the light switch then yeah, it just makes sense to use 3core+e or 4 core and use the black as the switch live and grey as the neutral with sleeving. Shove the grey into the neutral bar on the ceiling rose and wago the other end.

Or, tell your electrician to do that, i mean.

 

[telectrix]

the wholepoint of 3 core/E is to have all possibles at both light and switch. i/e/ L. / S/L / N / E. then there's no chasing out of Mrs. Bloggs's new decor when she decides on some smart tat.