1-Channel Relay Module for SCC—The SCC-RLY01 is a single-channel relay module for switching external devices. It contains one single-pole double-throw (SPDT) relay that is controlled by a digital line on a multifunction I/O device or module. To use the SCC-RLY01, you must also have a multifunction I/O device or module, an appropriate cable, and the SCC-68 or SCC-2345 carrier.