This is my first Motion control program and one of my first times dealing with analog control in general. I have created (LAD 5 Tensionctrl) in this program to control the speed of a material payoff in relation to dancer arm position. (I think this application screams VFD but they want me to use the existing equipment to prove the concept) I would really like some comments or suggestions from people with more experience.
Equipment:
SLC 5/03 in 7 rack chassis
1746-NIO4V Analog in/out
KBMG-212D with signal isolator board(SIMG 8832)
Problem: Right now the dancer arm is in complete control of the motor drive. At the end of the roll of material(roll diameter is small) pay off motor is not ramping fast enough to meet demand causing the dancer arm to reach full extension and the material is stretching. I have developed this program to turn over control of the drive to the PLC so that I can amplify the signal coming from the potentiometer, and ramp up the speed faster in relation to the dancer position. Everything seems to work exactly as expected but it has not been truly tested yet. Ignore the tension pressure input(I:5.0) on rung 0. That is there in case we decide to add a load cell to keep track of the actual line tension.
Getting the rewind, dead zone, and pay-off lined up was the part that I struggled with the most. The math here seems a bit clunky and awkward but yields the desired results as far as numbers go.
Any feedback or suggestions are greatly appreciated.
Thank you for your time.