Twin CAT - Stepper Motor in Open loop

hello Friends,

I have one problem. I have programme in Twin CAT
for Stepper motor which is running perfectally with
linear econder in closed loop control.

Now, i like to operate the motor in open loop and
also like to use linear encoder to read the acutal
position but without feed back.

Programme NC is using to control the motion in TwinCAT
manager and Position P and velocity PID controller (PID)
controller is selected.


Can you help me, how i should i approch ahead?

Thanks...!!!

You say open loop, but you want to use a PID. PID's require some form of feedback. So this musn't be the case.

Can you elaborate a little?

Yes, sure.

Actually, i like to read the motor actual position which is in close loop with Linear Encoder. So, because of feedback , the command is taking same value as Encoder suggest which contain some error.

I am interested to read that Error in Feedback loop.So, at same time
like to read motor actual position and actual value by encoder as well.

I found two ways, in beckhoff one is to implement simulation
encoder and second,two use internal encoder with module EL 7041 module.

I tried to use internal encoder and then,motor is making lots of noise.

Do you know how to configure Input and Output to use simulation encoder as additional encoder for same stepper motor ?

Thanks for your reply.