Smoke Alarms on separate supplies?

[diy_fun_uk]

Scenario: Hard wired smoke alarms in the hall and lounge. Hard wired hear detector in kitchen.
Requirement: Swap them out for interlinked alarms.
Electrician advice: Existing alarms not wired correctly, each is on a separate supply.

I've asked him to quote based on what he thinks needs done.

Is it the case the existing (non interlinked) alarms should never have been installed on their own supplies? Should they have been on the same supply from the outset?

This might be my stupid comment of the day, however given the interlinked alarms can communicate wirelessly, could the separate supply setup not remain in place?

 

[flameport]

If the link between them is wired, they must all be on the same circuit.
If the link is wireless, then they can be on different circuits.

 

[ericmark]

Oh what has god wrought? I had same argument about freezers on their own supply, the problem is if the supply trips, would you ever know? Yes we should test regular, and unless it failed on holiday so any battery back up has also failed on return, likely there will be some flashing light or buzzer to tell you it has failed, I use to use a rechargeable touch in freezer supply, so it would auto light on power failure.

Yes there are lights on freezer to say OK, but noting a light out is less likely to noting a light lit, so having smoke alarms and heat alarms on the same supply as lights seems to make sense. However upper and lower floors do tend to be on separate circuits, but what you are looking at is a risk assessment.

I am an electrician not a fireman, so what do I know? Most the firemen I know are more concerned in keeping fires going, why called a fireman on a railway engine but stoker on a ship never worked out, but I would suggest a trip to local fire station and ask them, get it from horses mouth so to speak.