The RSW10 is a switching matrix that can be controlled by a PC at up to 6000 ft (approx. 1829 m) using a twisted pair RS485 bus. The unit consists of a number of computer controlled relays run out to an external connector. This product can be used for either control or input selection. Some applications could be from production run automated test equipment to model railroad control. It can be used wherever you need computer control over light current(or sense lines). The units can be populated with a varying number of relays depending on the application.