Transmission error: data inconsistent (CRC2 error)

What does 20 mean?

A transmission error occurred, specifically indicating data inconsistency (CRC2 error) during PROFIsafe communication. This suggests corruption or incorrect data during transmission, which is critical for maintaining safety integrity.

• Electromagnetic interference (EMI) on the PROFIsafe communication line (e.g., Ethernet cable) causing data corruption during transmission.
• Faulty PROFIsafe cable (e.g., broken shielding, damaged conductors) between the safety PLC and the safety I/O device.
• Incorrect PROFIsafe parameters (e.g., F_CRC_Length) configured in either the safety PLC or the safety I/O device.
• Hardware defect in the PROFIsafe interface of the safety PLC or the connected safety I/O device.
• Network component malfunction (e.g., switch, coupler) causing data integrity issues for PROFIsafe frames.

Click steps to track your progress.

1. 1

   Inspect the PROFIsafe communication cable for physical damage and ensure proper shielding termination at both ends.

2. 2

   Check for strong sources of EMI near the PROFIsafe communication lines (e.g., unshielded motor cables, welding equipment).

3. 3

   Verify the configured PROFIsafe parameters, especially F_CRC_Length and F_WD_Time, for consistency between all safety devices.

4. 4

   Power cycle both the safety PLC and the associated safety I/O device.

5. 5

   Perform a cable test (e.g., continuity, attenuation) on the PROFIsafe communication line if possible.

6. 6

   Swap the suspected faulty PROFIsafe device (PLC or I/O) with a known good unit for testing.