How to configure RS485 communication for the NOVUS N321S Differential Temperature Controller?

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Setting up RS485 communication for your NOVUS N321S Differential Temperature Controller involves several key steps outlined in the device's manual. First, understand that the RS485 interface allows for a multi-drop bus topology, connecting the master controller to up to 31 slave controllers. Use a two-wire connection and note the maximum communication distance of 1000 meters. The controller uses the Modbus RTU slave protocol, a common standard for supervisory software. Available Modbus commands include reading holding registers (03) and presetting single registers (06). To configure the controller, assign each a unique address between 1 and 247 using the 'Addr' parameter. The controller's internal parameters, such as temperature readings, setpoints, hysteresis, and status information, are stored in registers, which are 16-bit words. The controller employs CRC checks to detect data errors, sending exception responses with error codes when issues occur. For electrical connections, use a shielded twisted pair cable with specifications like 3 x 24 AWG wires, 100 Ohms characteristic impedance, and ground the cable at both ends. Adhering to the recommended cable specifications and maximum length ensures reliable communication for your NOVUS N321S controller network.