Basic Principles of the Fire-Link

The Fire-link system connects to the buildings existing Fire Alarm panel most commonly on a spare bell circuit. This advanced fire alarm notification accessory has a fully addressable and supervised mini-horn (ISD) that may be installed anywhere there is an AC receptacle. The Fire-Link®II system broadcasts messages upon a carrier frequency and uses a special type of frequency modulation (Frequency-Shift-Keying, or FSK), to improve the system’s ability to overcome noise and pass these messages over the AC power lines. The system operates even when the AC power fails; due to an internal backup battery.

How the System Connects

1. Transformer provides power to house panel and suites or apartments.
2. House panel is wired to TPC & Choke.
3. The choke filters AC input power to the NMC.
4. TPC couples the NMC signal to each phase of the AC electrical distribution system.
5. TPC is wired to NMC Panel.
6. Fire Alarm Panel is wired to NMC.
7. Fire Alarm Panel initiates a fire alarm and triggers the NMC when required.
8. NMC sends and receives signals through the AC wiring to and from ISDs that are plugged into AC outlets. ISDs broadcast alarm or status messages as required by NMC periodically (per UL/ULC requirements). ISDs report their condition to the NMC according to their state.