New Lighting circuit - how are fans etc. connected

[Wavy Davy]

Hi,

I'm installing a new lighting circuit. Normal stuff - radial circuit with lights looped in on the ceiling roses. My question is - how are things like bathroom extraction fans, smoke alarms or an outside above door light normally included in a new circuit? Are they added as spurs off the ceiling roses or looped in?

Thanks

 

[Hellmooth]

Extract fan can be spurred off lighting circuit, usually fused down to 3A. Smoke alarms are usually put on a dedicated circuit, although they can be spurred off lighting circuit, some people prefer it as to turn of the smokes they would have to turn off the lighting circuit. Outside light can be spurred or extended off lighting circuit as well.

 

[Baker1988]

Agree with above extractor looped off the lighting circuit to a 3amp fused spur (if manufacturer details specify) and also to a 3pole isolator outside of the bathroom then to the extractor, as for the smoke alarm if it's a new install/rewire put them on there own circuit and the out side light just take off the closest lighting point with line and neutral at it.

 

[grandfortune]

Used to put smokes on there own circuit but not any more, the amount of times i see them with battery compartment open and circuit off is unbelievable , people just forget and think i must change that battery.

best to run it on its own circuit but put it in the same MCB as a lighting circuit, good for testing after as smoke circuit can be removed easily.

 

[kyle12111994]

I agree with most, I almost always put smoke detectors on their own circuit, a lot simpler most of the time!

 

[Deleted member 72666]

Agree with above extractor looped off the lighting circuit to a 3amp fused spur (if manufacturer details specify) and also to a 3pole isolator outside of the bathroom then to the extractor, as for the smoke alarm if it's a new install/rewire put them on there own circuit and the out side light just take off the closest lighting point with line and neutral at it.

Ooh, you're so 16th edition!

 

[Pete999]

Hi,

I'm installing a new lighting circuit. Normal stuff - radial circuit with lights looped in on the ceiling roses. My question is - how are things like bathroom extraction fans, smoke alarms or an outside above door light normally included in a new circuit? Are they added as spurs off the ceiling roses or looped in?

Thanks

What does your Electrician say about it?

 

[tazz]

It is all dependent on what Grade of smoke/heat detection is installed, and what standard the detection is manufactured to.
Grade E must be installed on its own non rcd or rcbo circuit. With prevision for anti tampering by key or tool and isolation to the detector for servicing.
Grade D can be installed on an existing or its own circuit, with the same prevision of tampering and isolation.

 

[Risteard]

Ooh, you're so 16th edition!

How do you make that out? It was called the phase conductor under the 16th Edition. It was the 17th Edition which renamed it the line conductor.

It will always be phase to me though.

 

[Deleted member 72666]

How do you make that out? It was called the phase conductor under the 16th Edition. It was the 17th Edition which renamed it the line conductor.

It will always be phase to me though.

Yeah, my bad! But I'm the same, it's etched into my brain as it's always sounded correct terminology since it was introduced in the 15th edition (that and live), that's why it sounded wrong when indeed it wasn't.

 

[Octopus]

I agree with most, I almost always put smoke detectors on their own circuit, a lot simpler most of the time!

not the best idea - see post #4

 

[Baker1988]

Ooh, you're so 16th edition!

Haha I started college during the 27th amendment one so we had to call it the line conductor any time we called it the live we lost marks and was told the answer was wrong as both line and neautral conductor is the live conductor haha

 

[Guest77]

Hi,

I'm installing a new lighting circuit. Normal stuff - radial circuit with lights looped in on the ceiling roses. My question is - how are things like bathroom extraction fans, smoke alarms or an outside above door light normally included in a new circuit? Are they added as spurs off the ceiling roses or looped in?

Thanks

Gasp!!!

 

[Wavy Davy]

Thanks for all the info. I'm laughing at how my newbie question sparked off so much debate! Glad you enjoyed it.

 

[Guest77]

I'm not laughing, if you need to ask this question then surely you should not be installing anything.

 

[Wavy Davy]

Haven't asked yet - intend to do most of first fix and then get one to check things over

 

[Guest77]

I thought as much.