On Fri, 25 Feb 2005 04:53:18 GMT, Takoma Park Volunteer Fire
Department Postmaster wrote:

Jeff Wisnia wrote:
Robert11 wrote:

Hello:

About to buy a few Kidde P12000 Smoke alarms.
The AC wired type, with both ionization and photocell.

Looked at their on-line instructions, and was surprised
to see that they say to install on circuits that are NOT
GFCI protected.

Seems surprising.

Anyone know the reason why ?

Thanks,
Bob
-----------------
" Make certain all alarms are wired to a single, continuous
(non-switched) power
line, which is not protected by a ground fault interrupter. "


That's probably to avoid the risk of electrical leakage to ground on
that circuit, like from an unoticed roof water leak finding it's way
into an electrical box, could trip the breaker and render the smoke
alarm system useless, without your being aware of it.

For the same reason, it's probably wiser to put the smokes on their own
breaker if possible. It'd be a fine mess if another appliance on the
same circuit as the smokes decided to overheat, catch fire, and then pop
that circuit's breaker before the smokes went off.

HTH,

Jeff

Jeff
Many localities require that the smoke detectors be installed on a
lighting circuit so that it is inconvenient to open the breaker to
silence an alarm.


Yeah this is a good idea, and so much so, I think it's in the
electrical code somewhere. Like it says don't run a dedicated smoke
detector branch, something else needs to be on it.

Have to check, since I can't remember where in the NEC it is, I might
be mistaking this for boca, or something else.

later,

tom @ www.ChopURL.com