The interface is used to monitor the contacts of an external sprinkler system, by the Fire Alarm System. The unit simplifies the testing of sprinkler systems connected to the fire control panel. It provides a means to easily switch OFF an alarm condition to the fire panel while showing a clear status indication.

The connection to the input is monitored for Fault (open or short circuit) and Alarm conditions. The output relay is powered from the detection loop. Relay will be driven directly by the condition of the Input, i.e. while the input is in Alarm the relay will be activated otherwise it will remain deactivated, but this is only true while the module is not disabled.