Communication fault with option

What does CEO mean?

This fault indicates a loss or error in communication with an installed option module (e.g., a fieldbus card or specific I/O module). By default, this condition triggers a full TRIP, inhibiting all ignition pulses and resetting the Ready signal, as the drive may not be able to operate safely or correctly without the option module's functionality. Manual reset is required.

• Option module (e.g., fieldbus card or I/O extension) not securely seated in its expansion slot, causing intermittent electrical contact.
• Damaged or improperly shielded communication cable (e.g., EtherNet/IP, PROFINET, RS-485) between the option module and the network switch or controller.
• Incorrect network configuration parameter (e.g., IP address in P5-21, baud rate in P5-25, or device address) set in the option module or the connected PLC/DCS.
• Insufficient or unstable 24VDC auxiliary power supply to the option module, leading to brown-outs or communication signal degradation during operation.
• Incorrect or missing bus termination resistors for serial communication protocols (e.g., PROFIBUS-DP, Modbus RTU) at the ends of the network segment.

Click steps to track your progress.

1. 1

   Power down the device using Lockout/Tagout (LOTO) procedure. Remove and firmly re-seat the option module in its designated slot, ensuring all locking mechanisms (screws, clips) are engaged.

2. 2

   Inspect the communication cable connected to the option module for physical damage (cuts, abrasions) or loose connections at both the module and the network controller. Use a certified cable tester to verify cable continuity and shield integrity.

3. 3

   Measure the auxiliary power supply voltage (e.g., 24VDC) at the option module's power input terminals (refer to module schematic for specific terminals, e.g., X1-1 and X1-2) using a calibrated multimeter. Confirm voltage is within specified tolerance (e.g., 21.6VDC to 26.4VDC).

4. 4

   Access the device's parameter menu or configuration software. Verify communication parameters (e.g., P5-21 for IP address, P5-22 for subnet mask, P5-25 for device address, or specific baud rate settings) match the network controller's (PLC/DCS) configuration for the option module.

5. 5

   For serial communication buses (e.g., PROFIBUS-DP, RS-485), visually confirm that end-of-line termination switches on the option module or external connectors are correctly set according to the network topology. Measure bus resistance if termination is suspected (e.g., 120 ohms for PROFIBUS).

6. 6

   Monitor the status LEDs on the option module (e.g., 'Network Status' (NS), 'Module Status' (MS), 'Link/Act'). Refer to the module's technical documentation for the specific meaning of LED states (e.g., flashing red often indicates a communication error).