A listed relay or other listed appliances connected to the fire alarm system used to initiate control of protected premises fire safety functions shall be located within how many feet of the controlled circuit appliance?

A listed relay or other listed appliances connected to the fire alarm system used to initiate control of protected premises fire safety functions shall be located within how many feet of the controlled circuit appliance?

• A. 3 feet
• B. 5 feet
• C. 1 foot
• D. 7 feet

Answer: (A)

Keeping a listed relay or similar listed device that initiates fire safety functions close to the circuit it controls ensures a fast, reliable actuation path and preserves the integrity of the listing. Locating the control within three feet minimizes the signaling path length, reducing potential wiring resistance, impedance, and interference that could delay or affect the function’s response during a fire. It also keeps the control and the appliance it governs as a tightly integrated unit, which simplifies inspection, testing, and maintenance and reduces the chance of miswiring or cross-talk between separate circuits. If the relay were farther away, longer wiring paths could introduce delays or faults and would not meet the intent of keeping the control close to its controlled circuit. So the required distance is three feet.

Keeping a listed relay or similar listed device that initiates fire safety functions close to the circuit it controls ensures a fast, reliable actuation path and preserves the integrity of the listing. Locating the control within three feet minimizes the signaling path length, reducing potential wiring resistance, impedance, and interference that could delay or affect the function’s response during a fire. It also keeps the control and the appliance it governs as a tightly integrated unit, which simplifies inspection, testing, and maintenance and reduces the chance of miswiring or cross-talk between separate circuits. If the relay were farther away, longer wiring paths could introduce delays or faults and would not meet the intent of keeping the control close to its controlled circuit. So the required distance is three feet.