TRP-C29 provides with 8 optical isolated digital input channels and 8-channel digital output open collector. All channel features screw terminals for convenient connection of field signals as well as LED?s to indicate channel status. Input channels are equipped with 3750Vms DC isolation, and surge protection on RS485 data lines that protect the module and devices against high power voltage input and ground potential differences. For easy user access, TRP-C29 can enter configuration mode and self-test mode with outer dip-switch. TRP-C29 support both ASCII and Modbus protocol, with a full set of command, dual watch-dog, and auto reset function the module can be bi-directionally remote controlled by PC in ASCII or Modbus RTU protocol.