SL−240C is a compact master/space controller (Kramer Control brain) with PoE. It can operate over Ethernet with control interfaces that include: four bidirectional RS−232, four IR, four GPI/O, and four relays. It controls devices such as scalers, video displays, audio amplifiers, Blu−ray players, sensors, screens, shades, door locks, and lights. Multiple Kramer Ethernet control gateways can be used to add remote I/O ports.