The M502M Addressable Interface Module is an intelligent interface device designed to connect compatible conventional 2-wire smoke detectors to an addressable fire alarm system. It provides a supervised conventional detector zone interface, allowing existing or dedicated conventional detection circuits to be integrated into intelligent addressable fire alarm networks.

The M502M supports one conventional detector zone and is compatible with approved UL-listed System Sensor 2-wire conventional smoke detectors. The module continuously supervises the connected detector circuit for fault conditions while providing accurate alarm and status reporting through the fire alarm control panel.

Operating on 15–32 VDC, the M502M provides a regulated 24 VDC power-limited detector supply and supports both Class A and Class B wiring configurations. Rotary decade switches allow simple address configuration, while the panel-controlled LED indicator provides clear module status indication during system operation and maintenance.

Designed for straightforward installation, the M502M mounts in a standard 4-inch square electrical box or optional SMB500 surface mount box, making it suitable for new installations and retrofit applications where conventional detection devices need to be integrated into an addressable system.

Key Features

• Intelligent addressable conventional zone interface module
• Connects compatible 2-wire conventional smoke detectors to addressable systems
• Supports one supervised conventional detector zone
• Compatible with UL-listed System Sensor 2-wire detectors
• Class A and Class B wiring capability
• Rotary decade switch addressing
• Panel-controlled LED status indication
• Operating voltage: 15–32 VDC
• Provides regulated 24 VDC power-limited detector supply
• Includes 3.9 kΩ end-of-line resistor
• Mounts in standard 4-inch electrical box or SMB500 surface mount box

The System Sensor M502M Addressable Interface Module provides a reliable solution for integrating conventional smoke detection devices into intelligent fire alarm systems, combining the flexibility of conventional detection with the advanced monitoring capabilities of addressable technology.