SI Motion CU: Checksum error safety monitoring functions

What does 201680 mean?

This fault indicates a discrepancy between the drive's calculated checksum for safety-relevant parameters (r9728) and the reference checksum saved during the last machine acceptance (p9729). This means that safety-relevant parameters have either been changed inadvertently, or a fault exists in the system impacting their integrity. This fault results in a STOP A, requiring immediate attention to maintain safety integrity and prevent unsafe machine operation.

• Modification of safety-relevant parameters (e.g., p9500-p9699 range) since the last machine acceptance, causing a checksum mismatch with p9729.
• Corrupted parameter memory in the drive CU, leading to an incorrect calculation of the current safety checksum (r9728) or stored p9729 value.
• Failure to re-commission or re-accept the safety functions after a firmware update on the Control Unit, leaving an old checksum.
• Incorrect value manually written to reference checksum parameter p9729, not reflecting the actual certified safety configuration.
• Internal hardware fault in the Control Unit affecting non-volatile memory or checksum calculation circuits.

Click steps to track your progress.

1. 1

   Connect to the drive system via STARTER/Tia Portal and compare the current safety checksum (r9728) with the saved reference checksum (p9729).

2. 2

   Review the parameter change log (if available in diagnostic buffer r0947) within the drive for modifications to safety parameters since last acceptance.

3. 3

   Perform a safety commissioning wizard (e.g., 'Safety Integrated Commissioning' in engineering software) to identify changed safety parameters.

4. 4

   If parameter changes are intentional and validated, perform a new safety acceptance (e.g., set p9729 to r9728 value) after verifying safety function operation.

5. 5

   Execute a full memory reset of the Control Unit (e.g., parameter p0976 = 1 for a power-on reset) and then re-download the safety project configuration.