Encoder calculation in plc

I am using an absolute encoder to monitor the position of motor.
The 12bit encoder is having gray output.
I have a doubt whether to convert the gray to binary in PLC.
Because if I am cutting out motor after encoder counts pulses equivalent to 32mm.Motor output is achieving only 30mm.
One revolution of motor moves 10mm, thatis 4096 pulses.


I am using PROFACE LT3201-A1-D24-C HMI with inbuilt PLC.

Please give a solution,if possible with program logic.

If I understand your problem well you have dead band problem.You "jump"between values.
This is one of the problems of using absolute encoders.
You should go with higher resolution encoder or incremental encoder.

sarathv

Convert the Grey Code into Binary
Using the method at http://www.plcdev.com/using_ladder_logic_for_gray_code_conversion

You now have 4096 counts (10mm) per Rev of the Motor so have 0.002 mm per count - use this to get better accuracy

Is the Motor a VSD or DOL?

If the Motor turns more than one Rev then some of the benefit of an absolute encoder may be lost (remembering position during power off).