Thanks for ur reply. Any idea why the PLC would run a programme with errors in it such as this. The machine seems to be working fine. Bit of background I took a backup of a PLC and found errors to be on it In The form of the original programmer had used commas instead of decimal points when entering REAL values. Eg 3,0 instead of 3.0. Was wondering why this would be the case and why the PLC would run a program with errors in it. Can't get in contact with the original programmer at this current time.