The relays can be configured in the COMbricks web server (Output Control menu) to respond directly to bus problems like; bus voltage too low, master lost and retries. This offers great applications to directly and independently act on the machine / process when the bus communication becomes unreliable. Especially when safety of human lives or the environment comes first.
Power switches, hold switches, indicators, backup systems, device I/O, doors and LED towers are examples of machine parts that can be hooked up to the relays.