When using SERCOS with a Die Accelerator there was a negative blip in the command profile at the start of the acceleration ramp. This blip did not exist when using analog.

The challenge for SERCOS is the motor encoder feedback is one sample old and the new command takes effect one sample delayed. The calculations attempting to account for this had a bug in them. They were attempting to make adjustments to the set-point ramp and when the ramp started.

The Set-Point ramp is now identical between SERCOS and analog. All adjustments for the old feedback and delayed command are now made in the loop. The error calculations in the loop are all made against the old Set-point which is also one sample old. The Lag Integral calculations that are removing the error will push the actual die position out ahead by one sample so that the actual die position will begin to match the new set-point by the time it becomes active and the die should be matching speed and position.

The only remaining customization in the set-point calculations for SERCOS is the tolerance test. Since we only know where the die was one sample time ago, the tolerance is compared with where the material was one sample time ago.