A place is wired like a circuit (normally referred to as a zone), starting up on the control panel and ending at the last gadget. Smoke detectors, heat detectors and simply call factors are placed on this circuit. Numerous zones are expected, based on the developing’s layout and size. NFPA http://firealarmsystems57899.blogripley.com/14227049/a-simple-key-for-fire-alarm-systems-unveiled