What's My Line?

"Servo drives change speed and position based on electronic feedback," he explains.

This feedback may travel quickly, but it takes precious time to accelerate or decelerate loads.

"At slower press speeds, electronic line shafts may react quickly enough to deliver the quality they promise," he adds. "However, at higher press speeds more material goes by before changes can be made. The servo is constantly chasing the correct position, but is always behind."