Sun TC
Member
Hello,
I am having an issue trying to get two motors to work in unison, particularly during accel/decel. I have attached a .pdf with the logic controlling the two motors. The pull roll drive pulls sheet material through a series folding plows and rollers, then pushes it into the cutoff assembly that cuts the sheets into even lengths. They work pretty well together steady state at a given rate, but during transitions from one speed to another, we get short sheets. When running at low speeds while jogging, all the sheets are short. Typical run speed is around 2000 sheets per minute, which translates to 400 cuts per minute on the cutoff assembly, as we get five sheets per cut. The system is pretty stable when steady state above roughly 900 sheets per minute.
Hardware being used is a controllogix L71S processor with Powerflex 525 25B-D010N114 Cutoff drive and the same drive as the pull roll drive. Both motors are 5 HP Induction motors. The Cutoff drive has a working encoder, the pull roll has one wired to the drive, but doesn't seem to be using it.
This line was upgraded from a SLC500 with Magnatek drives to the current setup about a year ago, by a third party integrator. We just found out about this little bug-a-boo this week. Is there a better way of coordinating these two motors so they stay together during transitions?
I am having an issue trying to get two motors to work in unison, particularly during accel/decel. I have attached a .pdf with the logic controlling the two motors. The pull roll drive pulls sheet material through a series folding plows and rollers, then pushes it into the cutoff assembly that cuts the sheets into even lengths. They work pretty well together steady state at a given rate, but during transitions from one speed to another, we get short sheets. When running at low speeds while jogging, all the sheets are short. Typical run speed is around 2000 sheets per minute, which translates to 400 cuts per minute on the cutoff assembly, as we get five sheets per cut. The system is pretty stable when steady state above roughly 900 sheets per minute.
Hardware being used is a controllogix L71S processor with Powerflex 525 25B-D010N114 Cutoff drive and the same drive as the pull roll drive. Both motors are 5 HP Induction motors. The Cutoff drive has a working encoder, the pull roll has one wired to the drive, but doesn't seem to be using it.
This line was upgraded from a SLC500 with Magnatek drives to the current setup about a year ago, by a third party integrator. We just found out about this little bug-a-boo this week. Is there a better way of coordinating these two motors so they stay together during transitions?