Rockwell Automation 150 MNL/SMC DIALOG+/APP-PROD GUIDE User Manual
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Application Profiles for the SMC Dialog Plus Controller
4-29
Figure 4.28 Towline Conveyor with Soft Start
Problem: A towline conveyor in a freight house had three motors to
drive the conveying system. Across-the-line starts caused
damage to the conveyor and spilled freight on the
conveyor. Occasionally, the conveyor would stop fully
loaded. An across-the-line start would then be needed to
provide enough torque to accelerate the load.
Solution: The conveyor OEM installed a single SMC Dialog Plus
controller to provide a smooth acceleration to all three
motors, reducing the starting torque of the motors and the
mechanical shock to the conveyor and load. In addition,
the controller could be configured to simulate a full
voltage start, allowing the conveyor to accelerate when
fully loaded. The OEM liked the SMC Dialog Plus
controller because of its ability to control three motors as
if they were a single motor, eliminating the need fo
multiple soft starters.
240 Vol
15 HP
Box Box
Motor Motor Motor
Chain
Conveyor