Smoke alarm - Wiring

[Dambo]

Hi guys,

On smoke alarms there is a N, IC (incoming?) and L terminal. What the IC for?

 

[Brian 157]

Inter-connect, for linking alarms together.

 

[a1]

Interconnecting other smoke alarms Mate.

 

[a1]

Twin & Earth to the First Smoke alarm, then 3 Core & Earth to all other alarms. (same type S/alarms).

 

[Dambo]

Twin & Earth to the First Smoke alarm, then 3 Core & Earth to all other alarms. (same type S/alarms).

Why is 3 core and earth needed to link the smoke alarms?

 

[Brian 157]

Using 3 core and earth gives a Line & Neutral (& CPC of course) to all detectors, powering them up, if one detects smoke & goes off the third core sends the signal to sound the other alarms.

 

[Dambo]

Cheers Brian

 

[bluetof]

There is no 'earth connection' on a smoke alarm, they are class 2.

 

[Dambo]

There is no 'earth connection' on a smoke alarm, they are class 2.

They still have an earth terminal though.

 

[sparkytim]

And the CPCs Are meant to be connected thru.

Even if nothing on the circuit requires an earth connection ( Class 2 ) the CPC still provides additional protection for the cable.

If someone cuts into it or thru it then the earthed CPC will assist a speedy disconnection thus ADS (Automatic Disconnection of Supply)

Its seems quite a few "Electricians" out there commonly cut off CPCs and do not connect them thru, along with failing to connect SWA armour at least at the supply end when not using it as CPC, NOT GOOD PRACTICE.

 

[batty]

And how will you do your loop test to test circuit with no cpc?