Fire Alarm Wiring For Elevator Recall and Flash Hat - Part 2

The elevator installers usually connect the signal wires from the fire relays to the elevator controller. The fire alarm system installer is responsible for getting the control wires to the elevator controller. Never remove access covers or open elevator control cabinets without explicit permission. Never route fire alarm control wires through a raceway or any conduit containing anything other than fire-related wires. The only exception would be telephone wires. 

Understanding how the elevator controller utilizes the fire alarm control wires to manage elevator operation can help you avoid certain issues and troubleshoot elevator operation related to fire alarm systems.

The elevator controller provides a positive voltage or reference ground as a common point, and the fire relays return that point to the controller for each fire condition. In all cases, the Fire Alarm System only needs to activate a relay to close or open the loop for each control.

In the case of voltage, it is VERY IMPORTANT not to let that wire go to ground. If you do it, it may pop a fuse within the elevator controller. 

While running a pair of wires for each relay back to the elevator controller is common, it is also usually Ok to route only four conductors and jump the common point between relays.

In cases of uncertainty, it is best practice to route a pair of conductors for each relay back to the elevator controller. The elevator installer will combine any conductors if needed.
Label each pair to match the associated relay. PRIME   ALT   HAT is perfectly acceptable. Remember that any main elevator lobby smoke/heat detector will activate the ALT relay. Any smoke/heat detector in any elevator lobby OTHER than the main elevator floor will activate the PRIME relay. Any smoke/heat detector in the elevator mechanical room or elevator hoistway will activate the HAT relay. 

Installing 18/2 FPLR firewire is usually okay, but you can never go wrong with 18-awg THHN. 

These relays must be programmed as NON-SILENCEABLE.  This will ensure that the relays stay activated until the fire alarm control panel is reset and not just silenced.