The SCM-4 is compatible with Potter's PFC-6000 series and PFC-8500 addressable fire alarm control panels. The SCM-4 is a contact monitor module used to supervise a circuit of dry contact input devices such as; sprinkler water flow, valve tamper switches or conventional pull stations. The SCM-4 module uses one (1) address on an SLC loop. The module is used to supervise a Class B circuit of normally open, dry contact input devices. The SCM-4 module includes one red LED to indicate the modules status. In normal condition, the LED fl ashes when the device is being polled by the control panel. When a device is activated, the LED will light continuously. In case of an open circuit, the LED will turn off.