TC.ENG (Customer) asked a question.
Use stepper encoder output in HSO module.
Productivity 2000 PLC
I have a stepper motor wired to an HSO module.
The stepper motor encoder is wired to an HSI module.
Right now my HSO is setup to output inches as position. The encoder on my HSI also outputs inches but when the stepper loses position they do not match.
How do I use the encoder value as my HSO position? or how do I update the HSO position to the encoder position so that I know if the stepper motor stalls or loses position?
That is a bit of a tricky one, as once you miss a step your encoder is simply going to be offset the output position and trying to move backward will just keep the same offset of the lost step. The HSI and HSO are two separate systems, they dont really work together as a closed-loop for an axis. You can use the HSI to monitor an encoder channel like you are doing now, but there will be some ladder logic to fix missed steps and get things back in sync.
The easiest way would probably be a home sensor. Find the home and then use set position to reset the HSO axis to 0. In the HSI hardware setup configure a tag to reset position and then when you find your home pulse that tag 1 scan to reset your HSI from the encoder back to 0 as well. This will get both things back in sync together.