https://www.vedardsecurity.com/conventional-fire-alarm-system-maintenance-panel-switch-p-22

A fire alarm system maintenance switch is a key-operated safety device that disables critical output circuits during service to prevent accidental alarms or suppression discharge. It ensures technician safety and avoids unwanted building evacuations.

Disconnect Release/Actuation Circuits

Cuts power to suppression agents (e.g., CO₂, clean agent) or notification appliances (horns, strobes).

Prevents accidental discharge or alarm during testing/repair.

Two-State Operation with LED Indicators

ARMED (Green LED): System active, circuits connected, normal protection.

INACTIVE (Red LED): Maintenance mode, circuits disconnected.

Key-Lock Security

Key removable only in ARMED position (prevents leaving system unsecured).

Restricted access to authorized personnel only.

System-Wide or Isolated Control

May disable entire system or specific zones/circuits.

Preserves supervisory signals (trouble alarms often remain active).

Facilitate Testing & Maintenance

Allows sensor/module testing without triggering building-wide alarms.

Enables safe replacement, cleaning, or troubleshooting of devices.

Typical Wiring & Specification

Power: 24 VDC (fire alarm standard).

Contacts: Form C (SPDT), rated 5A @ 250VAC / 30VDC.

Terminals: Common (C), Normally Open (NO), Normally Closed (NC)

Applications

Fire alarm control panels (conventional/addressable).

Suppression release systems (clean agent, sprinkler pre-action).

Notification appliance circuits (NACs).

Safety Note

Always return switch to ARMED after maintenance; verify green LED is lit.

Document all maintenance switch operations in the system log.