The Simplex 252-017 is a legacy auxiliary key-switch assembly for older Simplex fire alarm control panels, used for operator key control functions on installed systems.

Compliance

• Designed for use within UL 864 listed Simplex fire alarm control panel assemblies
• NFPA 72 National Fire Alarm and Signaling Code installations
• FM Approved system context (panel dependent)

Key features

• Auxiliary key-switch component for legacy Simplex panel front plates and controls
• Provides keyed operator control such as enable, reset, or access functions
• Mounts in the original control position within the host panel or enclosure
• Intended for repair, retrofit, and like-for-like replacement on installed systems
• Specified by Simplex part number to match the panel revision in service
• Used in commercial and institutional buildings running earlier Simplex platforms

Key-switch assemblies give panel operators a physical, keyed control over functions that should be restricted to trained personnel, limiting casual access and tampering at the panel. On older Simplex platforms these assemblies are matched by part number to the front-plate layout and wiring of a specific panel generation. Replacing the assembly restores the original control function without reworking the panel or its listing.

Verify panel and device family compatibility before ordering.