LW Modbus Manual

The PLC09 is equipped with four serial RS-232 asynchronous ports. For this application the software has been designed to connect to a Host computer using Modbus RTU Protocol on one serial port (labelled Port 1) and LIQUIDWATCH on another port (labelled Port 3). Port 2 is used for configuring the PLC09. The unit is equipped with battery backed up RAM which holds the configurable parameters.