240v Mains Detection

[john@total]

Hi Fellas

just a quick one, i have been asked by a landlord to install some non interlinked 240v smoke detectors in x3 flats.

Accourding to her and her council surveyor the 3 flats don't need to be interlinked, which i find strange, also do the detectors need there own feed stright to the dis board and put on a seperate rcd or can the be tapped off a lighting ring main?

john

[Rulland]

Hi, I would have suggested interlinked-but get in in writing if they don't!.

As far as the feed-the only stuff really that should be fed of the lighting circuit is lights/emergency lights IMHO.

Richard.

[aismoresecur]

BS 5839: Pt.6 states that a Grade D system (domestic mains smoke and heat alarms with a back-up supply) may be wired either from a dedicated circuit or from a regularly used lighting circuit; it also refers to radio- linked systems as being acceptably wired in this manner.

Wiring from a lighting circuit is advantageous as it is unlikely the user will deliberately or accidentally turn the circuit off, which is more likely in the case of a dedicated circuit.

Hope this helps.

Rab

[MatonTE1]

Hi Fellas

just a quick one, i have been asked by a landlord to install some non interlinked 240v smoke detectors in x3 flats.

Accourding to her and her council surveyor the 3 flats don't need to be interlinked, which i find strange, also do the detectors need there own feed stright to the dis board and put on a seperate rcd or can the be tapped off a lighting ring main?

john

Is it three rooms in a house or purpose bulit flats?When you say not interlinked,do you mean between each flat or in each flat?

[lawandorder]

I would wire them from the nearest reguarly used light, if they are on a dedicated breaker and it trips there is a good chance it will be overlooked whereas a non working light will be quickly noticed.