CI853 RS-232 module protocols:
COMLI can be used on the built-in COM3 port and optionally on the CI853 ports. The cable length can be extended considerably (to several km) using a fiber optic converter. RS-232C is the standard communication interface used for serial communication with COMLI. The CI853 supports Hot Swap. COMLI is an ABB protocol for data transmission between controllers. It is designed for asynchronous master/slave communication in half-duplex. COMLI protocol supports dial-up modems controlled from the application. CI853 supports both Master/Slave modes in COMLI.
MODBUS RTU is a standard protocol widely spread because of its ease of use and reliability. Modbus RTU is an open, serial (RS-232 or RS-485) protocol derived from the Master/Slave architecture exchanging information in half duplex mode. The Modbus functionality can be configured both on the COM ports of AC 800M and CI853. Module Redundancy is not available in MODBUS RTU. CI853 supports only Master mode in MODBUS RTU.
