The single relay output module is loop-powered, designed around a fully digital protocol and provides form C changeover contacts for control of equipment for DDA compliance such as vibrating pillows. The output channel is a normally de-energised relay switched on by a command from the control panel. The unit provides a fast and secure response, and incorporates a bidirectional short circuit isolator. Connections are made using plug-in terminal blocks which will accept conductors up to 2.5mm2. The unit can be mounted within an electrical box or enclosure.