SMC-50 Soft Starters

Our SMC™-50 fully solid-state soft starters are available with a current range from 90…520 A. Advanced monitoring and protection functions, superior communication capability, and Energy Saver mode all help this soft starter increase efficiency and reduce downtime.

Bulletin 150 SMC-50 Enclosed Soft Starters
  • Overview
  • What's New
  • Product Selection
  • Specifications
  • Software
  • Documentation
  • Resources
  • Applications


  • Provides 90…520 A range
  • Uses rated voltage: 200…690V AC, 50/60 Hz
  • Includes 17 start and stop modes
  • Includes four special operating modes
  • Includes three hardware expansion ports
  • Provides built-in electronic motor overload protection
  • Offers optional communication modules support multiple networks
  • Includes fully solid-state, continuous silicon-controlled rectifier (SCR) control
  • Offers optional Parameter Configuration Module, Human Interface Module, or PC-based software for programming and monitoring

Additional Information

Do you need a soft starter or an AC drive? What does your application require? When choosing between a soft starter and an AC drive what do you need to consider? Learn more in the following literature and blogs

To learn more about how the SMC-50 Soft Starter's unique starting and stopping profiles can meet your application needs, view this Virtual Demonstration. You can examine the construction and features of this soft starter in three frame sizes and in three dimensions. You will be able to peel back the product casing to see what is inside.

SMC-50 Soft Starters Now Available with Internal Bypass

This new offering combines the advanced functionality of the SMC™-50 control platform with the energy savings capabilities of an internal bypass power structure. After the motor has been started and reaches full speed, the controller closes the internal bypass contactors which increases energy efficiency and reduces heat output. This results in:

  • Reduced enclosure size
  • Reduced cost, avoiding the need for external bypass contactors

The SMC-50 fully solid-state unit continues to be available with normal and heavy duty ratings for customer flexibility in difficult and demanding applications.

To view commonly ordered and quickly available products, use the Product Configuration Assistant for our complete product offerings.


SMC-3, SMC Flex, and SMC-50 Smart Motor Controllers Technical Data150-TD009


  • SMC-50 Solid-state
    • cULus Listed (Open Type) (File No. E96956)
    • CE Marked per EMC Directive and Low Voltage Directive
    • CCC⋆ 
    • RCM
    • EAC
    • KCC⋆ 
    • ABS
    • Suitable for use with IE3 Motors (IEC 60034-30)
  • SMC-50 Internal Bypass
    • cULus Listed (Open Type) (File No. E96956)
    • CE Marked per EMC Directive and Low Voltage Directive
    • CCC⋆  (Pending)
    • RCM
    • EAC (Pending)
    • KCC⋆ (Pending)
    • ABS (Pending)
    • Suitable for use with IE3 Motors (IEC 60034-30)

⋆For updated certification status of controllers with 24V DC control power, consult your local Rockwell Automation sales office or Allen-Bradley distributor.

Standards Compliance

  • UL 508
  • EN 60947-4-2

Product Certifications

Certifications apply when product is marked. See our Product Certification site for Declarations of Conformity, certificates and other certification details.


Use Connected Components Workbench software with Microsoft Visual Studio® technology to program your SMC™-50 Soft Starter products.


Smart Motor Controllers Soft Starters Family Brochure150-BR144
Controlling High Efficiency Motors BrochureIE3-BR001
Enclosed Smart Motor Controllers Product Profile150-PP007
Global Short Circuit Current Ratings Product ProfileSCCR-PP003
SMC-3, SMC Flex, and SMC-50 Smart Motor Controllers Technical Data150-TD009
SMC-50 White Paper - New Control Advances; Sensorless Linear Acceleration150-WP005
Soft Starter Bypass Technology in Smart Motor Controllers150-WP006
When to Use a Soft Starter or AC Variable Frequency Drive White Paper150-WP007
SMC-50 Solid-state Smart Motor Controller for Managing Resistive Loads150-WP008
Slow Speed Applications using a Soft Starter150-WP009
SMC-50 Smart Motor Controller Quick Start150-QS003
ControlFLASH Firmware Upgrade Software User Manual1756-UM105
SMC-50 Solid-state Smart Motor Controller User Manual150-UM011
How Do You Control an Electric Motor When the Communication Network Fails?CMPNTS-AT001
Using an SMC-50 Solid-State Smart Motor Controller for Pump Protection150-AT003
Wye-delta and Solid-state Starters Application Guide150-AT005
DeviceLogix Technology for Industrial Applications193-AT001
SMC-50 Reduced Voltage Solid-State Smart Motor Controllers150-SR004
When to use a Soft Starter or an AC Variable Frequency Drive150-SP007
More Soft Starter publications in Literature LibraryAll Languages

Can’t Find What You Need?

Browse Literature Library where you can search for additional technical and commercial publications in more languages.

Product Certifications

Certifications apply when product is marked. See our Product Certification site for Declarations of Conformity, certificates and other certification details.

Configuration & Selection Tools

  • MCS Star — Configure a Modular Motor Control System.
  • ProposalWorks — Build complete quotes and proposals.

Other Resources

  • Firmware Downloads for SMC Soft Starters— Obtain firmware for your SMC Soft Starters from the Product Compatibility & Download Center.
  • Procurement Specifications — Visit our online resource to find the procurement specifications for this product.
  • SMC Estimation Wizard — Obtain a more advanced analysis of both the device and the system.
  • SMC Thermal Wizard — Conduct simple thermal analysis and selection of an SMC product for a given application.
  • Knowledgebase — Visit our online resource for technical information, support chat and forums, software updates, and product safety advisories/notices.


Watch the following videos to see how our SMC-50™ soft starters are used in the following applications:

Water Pump

The SMC-50 soft starters use new soft start technology to provide torque and speed control for starting centrifugal pumps and high-inertia loads. Through proprietary sensorless speed sensing and motor control algorithms, the SMC-50 soft starter can deliver even smoother pump starts and stops than was possible with previous pump-control methods.

Rock Crusher

The SMC-50 soft starters deliver improved performance on high inertia loads such as rock crushers through linear acceleration technology and torque control. Limiting peak current and torque shock yields consistent starting performances. Through advanced control and monitoring uptime is maximized and the need for system maintenance is reduced.

Band Saw

The SMC-50 soft starters minimize starting peak current and torque shock to the system. Slow speed operation enables inspection of saw blade tracking before the motor is brought to full speed. The Smart Motor Braking option enables the system to stop in a fraction of the time of a coast stop.

Compression Tank

The SMC-50 soft starters use linear start technology which is ideal for both high and low pressure applications such as those found in compression tanks. This soft starter also has an energy saver mode which optimizes energy usage when running lightly loaded motors.