paul renshaw
Senior Member
- Location
- Cordova, Maryland
Does 760.21(NEC 2005) include 120 volt smoke detectors such as the ones installed in dwelling unit bedrooms?
I couldn't agree more!A dwelling unit smoke detector is a single station unit and not a fire alarm system.
The smoke detectors installed in dwelling units are not fire alarms!The power source of non?power-limited fire alarm circuits shall comply with...
11.1.1* The performance, selection, installation, operation, and use of single- and multiple-station alarms and household fire alarm systems shall comply with the requirements of this chapter.
11.6.3 AC Primary Power Source. The ac power source shall comply with the following conditions:
(5) Operation of a switch (other than a circuit breaker) or a ground-fault circuit-interrupter shall not cause loss of primary (main) power.
No matter what the wording says in the various sections of Article 760, the scope limits the application of these rules to "fire alarm systems".760.1 Scope.
This article covers the installation of wiring and equipment of fire alarm systems including all circuits controlled and powered by the fire alarm system.
That is my understanding of NFPA 72.I guess all the smoke detectors in a house, even though interconnected, do not meet the definition a "fire alarm system" as far as the NEC is concerned.