Rockwell Automation 150 MNL/SMC DIALOG+/APP-PROD GUIDE - Manual (Page 102)

4-20 Application Profiles for the SMC Dialog Plus Controller
Figure 4.19 Centrifuge with Current Limit Start
Problem: Because of the high starting torque, the gearbox to a
centrifuge was being damaged. A reduced voltage starter
was desired because this motor was near the end of the
distribution line. In addition, the incoming power was
unbalanced. A controller with a circuit breaker
combination enclosure was needed. When the enclosur
door was open, the controller’s circuit boards could not
be exposed.
Solution: The SMC Dialog Plus controller was installed. It was
programmed for a 27-second, 300% current limit start,
which limited the starting torque of the motor and the
shock to the gearbox on start-up. The Energy Saver
feature reduced the voltage to the motor when it was
running lightly loaded. The SMC Dialog Plus controller
was ordered as a combination controller with a circuit
breaker. The SMC Dialog Plus controller has no exposed
circuit boards, fulfilling the packaging requirements.
480 Volts
250 HP
Centrifuge
Gearbox Motor