Cause: RS-485 communications error (COM port 1) comes when a communications error occurred during RS-485 communications. This means the drive is unable to establish or maintain reliable communication over its primary RS-485 serial communication port 1.

er8 fault in fuji FRENIC MEGA drive indicates RS-485 communications error (COM port 1). This means the drive has lost or failed to establish communication on RS-485 serial port 1.

• Check the host equipment.
• Power Cycle the Drive.
• Check communication parameters on the drive.
• If multiple devices are on the bus, test with only one drive connected.