What happens?
The process image mapped into a variable does not correspond to the process data of the EtherCAT device.
When does the problem occur?
If the process data of an EtherCAT device is mapped to an ARRAY variable that has already been declared, the process data is only mapped correctly to the first ARRAY element. The value of the remaining ARRAY elements does not change.
Which products are affected?
PLC Designer from V3.5
Diagnostics options:
None
Short-term measures/recommendations:
If process data of an EtherCAT device is of the ARRAY data type, create a new variable in the 'EtherCAT I/O image' tab and map the process data value to this variable. Do not map the process data to a variable which has already been declared.
Evaluation:
If process data is mapped to an ARRAY variable which has already been declared, the process image in the variable will not be correct. The ARRAY data type is rarely used for process data of EtherCAT devices. The above-described recommendation provides a workaround for the function restriction.