Would you recommend this....r.e.smoke alarms?

[LlandrilloSpark]

Morning Fellas

Inspecting a mains operated multilinked smoke & heat alarm system this morning for a house of multiple occupancy.

Having previously worked in the property I noticed the system has its own 6A MCB which is RCD protected

Would you recommend that the system has a NON RCD protection?, the cabling is either exposed in the loft/basement and can clearly be seen and when it is in the house it is run in PVC mini trunking.

Ive known them to be bunched in with lighting before now, the thinking maybe if your lights trip you no the alarms are out, but if the lights trip in the night when everybody asleep..thats no good to anyone

Cheers

 

[KINKY]

Are they battery backed?

If the installtion method does not require an RCD than I would feed them from a non RCD protected way.

 

[bozobro0]

Fire detection circuits must be supplied independently of other circuits and not protected by an RCD protecting multiple circuits. 560.7.1 .

 

[LlandrilloSpark]

thanks guys

 

[roukel01]

Fire detection circuits must be supplied independently of other circuits and not protected by an RCD protecting multiple circuits. 560.7.1 .

That reg is for a fire alarm circuit and not an interlinked Smoke detection circuit.
Building regs prefer that a smoke detection system is connected to a well used lighting circuit when an RCD protects multiple circuits so that the user soon realises that the power has been lossed to the smoke detectors. (Usually through a switched fuse spur)

 

[LlandrilloSpark]

So if i spur it of the lighting mcb and put through a FCU with neon (outside the intake cupboard) then when the occupants see the neon out then they know there could be a problem.

 

[roukel01]

from what you've described, you dont need to do anything to it, if the RCD protects other circuits (eg lighting or sockets) the the residents are soon going to know that the RCD has tripped.

 

[bozobro0]

Sorry Rouke,my mistake,This is from Building Control Guidance-Note 16

Smoke detectors should be powered by a mains supply connected to a separate circuit on the dwellings distribution board (consumer unit). If there is any other equipment connected to the electric circuit, then the smoke detectors should also have an in-built battery back-up -which will operate the alarm if the power fails. NOTE -If you use a battery backed up smoke detector they can be connected to a regularly used lighting circuit this avoids prolonged power disconnection.