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A Simple Explanation: The Difference Between a Soft Starter and a Variable Frequency Drive

A Simple Explanation: The Difference Between a Soft Starter and a Variable Frequency Drive

Posted by Beckie Sullivan on Aug 8th 2022

This is a common question and, full disclosure, this is a very basic blog on the differences.

 

A VFD (variable frequency drive) can increase/decrease the speed of a motor. If you need motor speed control a variable frequency drive is what you need.

 

 


A soft starter is only involved in the starting and, sometimes, stopping of a motor. A soft starter will allow you to start the motor at a reduced voltage, gradually increasing during startup until you reach full speed. This gives you a controlled ramping up to full speed.

Quick Overview:

 

● If you need to vary the speed of the motor as it is operating you will need an AC drive.

● If you are going to start the motor and ramp it up to full speed a soft starter might be all you need.

 

Let’s use one last real world example to clear things up, someone once explained this to me using a car:

  • soft starter is similar to slowly pushing on your gas pedal to increase to the speed you want and then staying there.
  • drive would allow you to push to increase, remove to decrease and adjust your speed as needed.
  • If you didn’t use anything it would be similar to just slamming all the way down on the gas pedal.
  • Which options do you think are better for your car and all the parts involved?

Want to learn more? Check out this video by RealPars!

 

Now that you need whether you need a drive or a soft starter, let us help you find which model would work best in your application. Our technical support is ready!