Cause : Data defect comes when the program detects incorrect written address when translating the program source code (e.g. the address exceeds the range) during PLC downloading, then PLdA warning occurs.

PLdA warning in delta ms300 drive indicate Data defect, the external Modbus has written/read incorrect data to internal PLC program.

1. Check if the upper unit transmits the correct command.
2. Check if the program is correct and download the program again.
3. If the fault does not exist, the warning automatically clears.