Rockwell Automation 150 MNL/SMC DIALOG+/APP-PROD GUIDE - Manual (Page 123)

Application Profiles for the SMC Dialog Plus Controller 4-41
Figure 4.40 Ball Mill with Soft Start and SMB Smart Motor Braking Option
Problem: The gearbox on a ball mill was being damaged by across-
the-line starts. The result was extra maintenance time to
keep the mill operating. Due to the high inertia of the
load, the coast-to-stop time was approximately five
minutes. The application required a soft start and
braking package in a single controller since panel space
was at a premium.
Solution: The SMC Dialog Plus controller with the SMB Smart
Motor Braking option was installed on the ball mill. The
soft start reduced the shock to the gearbox on start-up.
The SMB Smart Motor Braking option reduced the
stopping time and increased the productivity of the mill.
The SMC Dialog Plus controller with the SMB Smart
Motor Braking option was installed in the same space in
which the previous contactor had been mounted. No
additional power wiring was required.
480 Volts
250 HP
Loading Port
Drum
Substance
Ball Shot
Gearbox Motor