Smoke detectors + 17th edition

[stevie h]

Doing a rewire at the mo , its my 1st one under the new regs , going to use a 17th edition double split RCD board , are the mains smokes ok to go on one side of the board ? or do they need to go on there own RCBO

Cheers

Ste

 

[robbieb29]

i'm a bit confussed, can a smoke detector be protected by an rcd on the smoke detector's own circuit. if the smoke detector has its own battery backup, can it be still be protected by rcd. Part P does state it should be on its own circuit, but should it be RCD protected. I'm thinking if if was and the RCD tripped and the battery was dead, then that smoke alarm would not work.

 

[telectrix]

smokes only require RCD if the cable/s are buried <50mm deep without earthed mechanical protection.

 

[PC Electrics]

I understand the Logic in this, But irrespective of where the Smoke detector circuit is placed it still has to have a means of isolation of its own..So surely the circuit could be turned off anyway???

Not so. This 'advice' is in AD-B, where the wording is 'should' not 'must'. Anyway you could still take the smokes supply back to the MCB and label the leg - not easy for the average owner to 'turn off' but still complies with AD-B advice

 

[Spudnik]

Isolation for smokes can be achieved by removing them from the base, or unplugging them.

No need for a separate isolator.

Talk about thread resurrection!