A01691 — SI Motion: Ti and To unsuitable for DP cycle

A01691 is raised when the DP cycle of the PROFIBUS communication is used as the actual value acquisition cycle for the SI Motion safe movement monitoring functions and the configured communication times Ti and To do not fit this cycle. Depending on the drive's configuration, the same condition can also be issued as a fault.

• The configured times for the PROFIBUS communication are not permitted, while the DP cycle serves as the actual value acquisition cycle for the safe movement monitoring functions.
• With isochronous PROFIBUS, the sum of Ti and To is too high for the selected DP cycle. The DP cycle should be at least 1 current controller cycle greater than the sum of Ti and To.
• Without isochronous PROFIBUS, the DP clock cycle must be at least 4x the current controller clock cycle.
• If this alarm is not observed, the message C01711 or C30711 – with the value 1020 ... 1021 – can occur sporadically.

1. Configure Ti and To low so that they are suitable for the DP cycle, or increase the DP cycle time.
2. Alternative when SI monitoring integrated in the drive is enabled (p9601/p9801 > 0): use the actual value acquisition cycle p9511/p9311 and set it independently from the DP cycle. The actual value sensing clock cycle must then be at least 4x the current controller clock cycle; a clock cycle ratio of at least 8:1 is recommended.

• p9601 – SI enable functions integrated in the drive (Control Unit): shows whether the integrated SI monitoring is enabled, which decides whether the alternative actual value acquisition cycle may be used.
• p9801 – SI enable functions integrated in the drive (Motor Module): the corresponding setting to check together with p9601.
• p9511 – SI Motion actual value sensing cycle clock (Control Unit): the alternative actual value acquisition cycle, set independently from the DP cycle.
• p9311 – SI Motion actual value sensing clock cycle (Motor Module): the corresponding cycle, likewise set independently from the DP cycle.

The message appears as an alarm and requires no acknowledgement; while it is active, the drive takes no automatic reaction. If the drive's configuration raises the same condition as a fault instead, POWER ON is required to acknowledge it before the drive can be restarted. Adjust Ti and To or the DP cycle as described above so that the message does not reappear.