Smoke alarms - RCD main switch

[Dambo]

When the main switch in a consumer unit is an RCD are the mains fed smoke alarms controlled by an MCB as opposed to an RCBO?

 

[ianmacd]

well unless its a TD main switch, an RCBO would not allow for discrimination so would have to be an MCB.

 

[SLIPSHOD & SLAPDASH]

Is this an exam question or a problem you have ? What do you mean by 'controlled by' as both the RCD and the MCB control it. You would not have an RCBO if there is a RCD main switch.

However, it is not correct to have smokes on any type of RCD device which also covers socket outlets for obvious reasons.

 

[Lenny07]

regarding your question we work for local authority and it is in their spec to wire smokes alarms off downstair lights which in turn is protected by a 61009 rcbo!

 

[Dambo]

Is this an exam question or a problem you have ? What do you mean by 'controlled by' as both the RCD and the MCB control it. You would not have an RCBO if there is a RCD main switch.However, it is not correct to have smokes on any type of RCD device which also covers socket outlets for obvious reasons.

I was just curious how the smoke alarms would be protected when the main switch is an RCD i.e. an RCBO not be applicable.

 

[SLIPSHOD & SLAPDASH]

I was just curious how the smoke alarms would be protected when the main switch is an RCD i.e. an RCBO not be applicable.

Ok

---------- AUTO MERGE Post added at 21:21 ---------- Previous post was at 21:17 ----------

When the main switch in a consumer unit is an RCD are the mains fed smoke alarms controlled by an MCB as opposed to an RCBO?

So you meant to say 'Should' after RCD instead of 'are' ?

If so its a bit of a grey area, but as i mentioned earlier i interpret the various regs as a fire alarm system, either smokes in a domestic or a full system should not be connected to the same RCD as any socket outlets. So that rules out using a consumer unit with a main switch RCD or a '17th edition' board that's not high integrity