Johnson Controls M301MJ Miniature Monitor Module

Johnson Controls M301MJ is a miniature monitor module that supervises a Style B (Class B) circuit of dry-contact input devices. The M301MJ is intended for use in intelligent, two-wire systems where the individual address of each module is selected using rotary switches. It provides a two-wire initiating device circuit for normally-open-contact fire alarm and security devices. The M301MJ can be used to replace M501MJ modules in existing systems. Mounts to single-gang box behind the device it monitors.