CHQ-MRC2/FS(SCI) Fail Safe Mains Relay Module with SCICHQ MRC2 FS(SCI) Fail Safe Mains Relay Module with SCI Manufactured by Hochiki. Model CHQ MRC2 FS(SCI) is a Single Input Output Module, which provides a single, mains rated relay output for the control of such devices as dampers, access control equipment (e. g. door magnets), extractors or plant and equipment shutdown. The monitored input can be used for local power supply fault monitoring or as a general purpose input. The unit is also available as a