Which products are affected?
ESP-SP-POS - Software Package Positioner V2.2
How is the reaction?
The difference between the actual position and the position setpoint, that is the following error is provided at the output of the profile generator in a fast task (2 ms). The evaluation, that is the comparison with the following error warning limit and the following error limit is performed in a slower task (5 ms). In the previous version the read access for the 32-bit value from the 5 ms task could be interrupted by renewed write access from the 2 ms task (data inconsistency). As a result the monitor is triggered sporadically because the following error limit is exceeded by the erroneous values.
The data from the evaluation is now consistent.
Possible diagnostics?
The problem only occurs with specific task constellations and is very difficult to trace.
The monitoring for the following error warning limit and/or the following error limit are triggered sporadically even though the drive has reserves to reduce any following error that occurs.
To check, the difference between the setpoint and actual position can be formed directly at the MCTRL and displayed as an oscillogram. If, despite the triggering of the following error monitoring, the difference in within the limits, then it can be assumed that this data inconsistency is present.
Short-term measures/recommendations?
The frequency of the occurrence of the error can be reduced by changing the task configuration. Higher priority tasks such as the template tasks and high task utilisation should be avoided.
Evaluation:
The error does occur in general practice, but only in specific constellations in the task configuration (from previous experience only once the system is in the field). A permissible process takes place when the problem occurs ('Trip-Set'). Damage to product and machine is not to be expected.
