Allen-Bradley SMC-50, User Manual

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18 Rockwell Automation Publication 1560F-UM001A-EN-P - June 2019
Chapter 1 Product Overview
Selectable Kickstart
Selectable kickstart provides a power boost at start-up that is user-adjustable from
0…90% of locked rotor torque. The additional power helps motors generate
higher torque to overcome the resistive mechanical forces of some applications
when they are started. The selectable kickstart time is user-adjustable from
0.0…2.0 seconds.
Figure 5 - Selectable Kickstart
Pump Control Mode
This mode is used to reduce surges in a fluid piping system and the resulting fluid
hammer or check valve slam caused by starting a centrifugal pump at full voltage
and full speed. This mode also reduces pump cavitations, increasing pump life. To
provide these benefits, the SMC-50 module’s microprocessor generates a motor
starting curve which follows the starting characteristics of a centrifugal pump and
monitors operation during start to ensure reliable pump starts.
1. Consult factory if start time settings over 30 seconds are required. See
Appendix B for controller duty cycle ratings.
2. The Pump Control option functions only for centrifugal pumps. It is not
suited for positive displacement, piston, or other types of pumps.
3. The Pump Stop option functions only for a centrifugal pump running at
greater than approximately 2/3 of the motor rated horsepower.
4. Pump applications with input and/or output valves that are closed during
starting and/or stopping may not benefit from the Pump Control option.
Consult the factory for applications with valves.
5. For starting or stopping times longer than 15 seconds, power fuse selection
should be reviewed to ensure no element damage occurs. The fuse
minimum melting time-current characteristic curve should be consulted to
ensure that, at 1.1 times the full voltage locked rotor current of the motor,
the actual starting or stopping time does not exceed 75% of the fuse
melting time.
Kickstart
100%
Initial
Torque
Start
Time (seconds)
Run