The Dry Contact Input RIB series offers all the advantages of the standard RIB line; plus, it can be activated by a wide range of dry-contacts such as thermostats, switches, other relays, solid-state switches, etc. The Dry Contact Input RIB provides the low-voltage (Class 2) power needed to activate the relay (self-powered) - just close the dry-contact input. The power to energize the relay can be brought to the relay on a separate pair of wires along with the control output of the controller, or can be a local power source near the relay. The relay contacts are isolated from the input power and the dry contact input; thus, they can be wired to switch any other power-load or low-voltage load (see specifications for contact ratings). One model can be used for many installations (model RIB21CDC can operate from any voltage from 120Vac - 277Vac; see specifications for the input power of other models).