ECN Forum Forums Code Related Discussion NEC & other Code issues Smoke Detectors In Series

Hi,
Whast is the lowdown on Smoke Detectors in residential?

They are required to be wired in series now so that if one goes off they all go off?

I know I need one in each bedroom and on each level of the home, is there anything else I need to watch?

Thanks for any replies.

-regards

Greg

What you describe is probably the best system but chec with the local fire marshal. Placement of smokes is the FD call.

smokes(line voltage ones) are interconnected, but they are still in parallel. Smokes that are part of a FA system can be in series, but can also be parallel, depending on which set of contacts you use. Fire dept of building codes in your area is what I would use for placement.

Line voltage smoke detectors for residential are interconnected with 14-3 wire and if one sounds they all will go into alarm.I use BRK and use photo electric type within 20 feet of a bathroom or kitchen and ionization elsewhere.We use the type with battery backup.

Put 1 on each level near stairwell and add a 2nd if the floor area is over 1200sq feet. Also put 1 in each bedroom. I put heat detectors in the garage and also in an attic with mechanical equipment.Keep 3 feet away from ventilation duct feed and returns.

Connect to a AFCI circuit according to 2002 NEC.

Do not use more than 12 smoke detectors interconnected.

shortcircuit

Hi,
Thanks for the replies. The line voltage feed is seperate from the 14/3 used to interconnect right?

I was wondering what type of cable was best to interconnect them.

All smokes on AFCI even if not in bedroom?

In the area where this house is at there is no code or inspection.

Should I even bother with interconnection? Sounds like a good idea though.

Do they have to be AC now or can they be a ten year lithium?

-regards

Greg

We are required to place one in each bedroom, and one immediatly outside each sleeping area. They are all required to be on the same circuit, a dedicated circuit, connected with 14/3. We use the red wire for the interconnect. Since some of them are inside the bedrooms, the circuit must be on an AFCI.

the interconnect is in the 14-3(Red wire). Also, when placing detectors, be sure to not place them within 4" ( I beleive) of the corner of the room, where the ceiling meets the wall. The smoke can't get to them.

The line voltage is not seperate from the 14/3. If interconnected and not all on the same breaker phasing would be critical.

Hi,
Ok..14/3--BK & W = PWR & R = Signal right?

Pretty straight forward..

Makes sense too..

Why run an extra cable for signal..I gues since the conductors all have the same insulation rating there is no problem with different voltages?

I am guessing that the signal wire is a contact that is either open or closed until the system goes into alarm.

Thanks for the replies..

greg



[This message has been edited by mustangelectric (edited 12-10-2004).]

we are required to install 1 on each floor level, 1 in each bedroom, and 1 in the hallway just outside of the bedrooms but if other bedrooms are not within 10' of that smoke you need to install another.. it is all up to the building inspector