Which products are affected?
EPL-10200 (Drive PLC V8.1)
Eliminated function restriction:
The default setting value for the synchronisation phase (C1122) has been changed to 0.460 ms. As a result, this setting is larger than the max. possible jitter of a sync telegram.
Which products are affected?
EPL-10200 (Drive PLC V6.5)
What happens?
Sync-controlled CAN telegrams are received and evaluated by one task cycle too late. If the setpoints are selected via CAN, this behaviour may lead to a setpoint step-change.
When does the problem occur?
The default setting value for the synchronisation phase (C1122) is lower than the max. possible jitter (with regard to the time) of the sync telegrams to be received. The response described before occurs if the synchronisation of the drive controllers has been activated via CAN-Sync (C1120 = 1) and the default setting of the synchronisation phase (C1122) is used.
A sync-controlled CAN telegram is not accepted by the PLC target system unless a sync telegram has been received after the receipt of the CAN telegram. This data can than be accessed out of the PLC program in the next task cycle. If the synchronisation phase is shorter than the jitter of the sync telegram, it may happen that the sync telegram is not received before the task has been started. In this case the PLC target system accesses the data which has been received in the last task cycle.
Possible diagnostics?
Check the value under code C1122, e. g. by using the Global Drive Control software.
Short-term measures/recommendations?
Set the synchronisation phase to (C1122) 0.460 ms at least.
Evaluation:
According to the default setting the value for the synchronisation phase is too low. However, the drive synchronisation is not active after the default setting has been loaded. Thus the too small value has no direct consequences if the default setting has been loaded. This means that the synchronisation phase is to be changed, too, whenever the drive synchronisation is activated.
