FREE Shipping on orders over $75!



An Innoraymond soft starter is a sound investment for anyone who is regularly working with motorized tools, but many are unaware of exactly what a soft starter is and what it does. 

What is a Soft Starter?

Damaging a motor is easier than you think. In fact, every time you use your motorized power tool like your miter saw, you are causing mechanical wear and tear. The primary culprit is huge inrush currents. 

A soft starter is a device that aims to minimize the impact of the inrush current on the motor when it’s started. 

How do soft starters work?

A soft starter significantly reduces the stress on a machine, preventing damage. There are several different types of motor-driven equipment that benefit from the use of a soft starter. For example, pumps, fans, and conveyors are all served well by a soft starter. Soft starters can even be used by equipment such as escalators to save energy, stopping and starting automatically as needed. 

Soft starters help by gradually increasing voltage in stages. Without a soft starter, the motor would receive the full voltage immediately upon starting. By delaying the amount of power that is used, these devices prevent damage and reduce the stress on the system over time. 

Soft starters don’t change the running speed of the motor, so performance is not impacted by the use of the device. 



Single, Two, and Three Phase Soft Starters

Soft starters come in single, two, or three phase units. Each unit is appropriate to use in different circumstances because they function differently. In a single-phase soft starter, the unit controls the starting torque, but doesn't always reduce the starting surge current. This means that a single phase soft starter is not appropriate for a motor application with a high inertial load. 


Open or Closed Loop

A soft starter will either run on an open or closed loop. In an open loop unit, there is no current feedback loop. These are designed to offer a pre-selected voltage profile that controls the starting phase of the motor, but doesn’t protect the motor. A closed loop system, in contrast, is designed to provide protection for the motor and features current feedback. This gives the operator more control over the current level when starting the motor. 

An open-loop system has a set ramp up that is not dependent on the speed of the motor or the current. The best setting on an open-loop system gives the motor breakaway torque when it starts. This makes the start gentler; however, they are not able to produce a specific torque. In contrast, a closed loop starter will track the output and respond accordingly by adjusting the input voltage automatically so that the motor can reach a specific voltage. 

There are also other closed-loop units that will adjust voltage in order to keep acceleration constant. They are designed to monitor the input current on one phase to ramp up the voltage. These units then compare the current to a set point. Finally, they ramp up once the current generated is higher than this point. 



For motors that need varied onset torque, a soft starter that offers current ramping is your best bet. This type of soft start will take the current from the start value to a limit that is programmed for a set length of time. 


The Benefits of Soft Starters 

A soft starter is advantageous when you’re using any type of motorized equipment for several reasons. First, by allowing the motor to start more smoothly, the tool does not glitch or jump, making it easier to use. This means that you will be more comfortable when using a power tool for an extended period of time, and you will be able to use it with more precision from the beginning. By altering the initial voltage, you don’t have to worry about the full current immediately causing your machine to jump. 


Finally, when you use a soft starter with a power tool, you extend the life of that machine. This means that you are able to be more productive with less worry about your tool breaking down at inopportune moments. 

We hope that this has given you some insight into soft starters. If you have any further questions, we would be happy to help! In the meantime, shop our selection of high-quality soft starters here. All made in the U.S.A.!

Powered by Top Rated Local®