Variable Frequency Drives

A Variable-Frequency Drive (VFD), alternatively known as adjustable-frequency drives, adjustable-speed drives, variable-speed drives, micro drives, inverter drives, or drives, is an AC motor drive system. It controls speed and torque by adjusting the input electricity frequency, influencing voltage or current variation based on topology.

VFDs and Soft Starters

The two most common types of controls that we carry are Variable Frequency Drives (VFD) and Soft Starters. VFDs can also be referred to as ‘Variable Drives’ or simply ‘Drives’.

We understand that it can be hard to find the exact control system that meets your needs. That’s where we come in – our experienced professionals can help you pick the right one for you, ensuring that your motor runs smoothly and efficiently.

What are the Types of Motor Controls at Universal Rewind

There are two primary types of electric motor controls available, each with its own unique set of benefits and limitations. The most common types include:

Soft Starters

A soft starter is a device that is used to start AC motors smoothly, reducing the stress on the motor, the electrical system, and the connected equipment. Soft starters are similar to traditional starters in that they are used to start an electric motor. However, unlike traditional starters, soft starters gradually increase the voltage supplied to the motor, reducing the stress on the motor and improving its overall efficiency. Soft starters are widely used in the industrial world to protect motors from damage caused by high inrush current during starting. They also help in reducing the starting time of the motor, which can result in increased energy efficiency and improved process control. Soft starters are a less expensive option, however, they do not boast the same features and benefits as VFDs.

Variable Frequency Drives

A variable frequency drive (VFD) is an electronic device that controls the speed and torque of electric motors, which helps to improve the overall efficiency of an electrical system. They work by adjusting the frequency of the power supplied to the motor, allowing the user to precisely control the motor’s speed and torque. They are very similar to Soft Starters, with the one key difference being they control speed, whereas soft starters do not. VFDs are also known as AC drives, adjustable frequency drives, or variable speed drives.

We carry Soft Starters and VFD’s from TECO. Give us a call or Contact Us to learn more – our team is happy to help you source the proper starter for your application.

Choosing the Right Controls for Your Application

When you choose the right control for your electric motor, it is important to consider the specific requirements of your application. Take into account factors such as the motor type, the load you are driving, and the desired speed and torque. Assess the level of control your application needs. If your application demands a large inrush of current but does not require speed control, then the best option is a soft starter. On the other hand, if you require speed control, a VFD becomes a necessity.

For instance, if you seek a simple and reliable control solution for a basic application, you may find that a soft starter proves to be the best option. Conversely, if you need precise control over your motor’s speed and torque, you may want to consider choosing either a variable-frequency drive or a soft starter.

See More on VFDs and Softstarters

Applications and Industries that use VFDs

VFDs are commonly used in a wide range of industries, including manufacturing, mining, oil and gas, water treatment, and more. Some of the specific applications of VFDs include:


VFDs are used to control the speed of conveyors in manufacturing, food processing, aggregate operations, and other industries. This can improve the efficiency of production lines and reduce the likelihood of bottlenecks.

Pump control

VFDs are used to control the speed and torque of pumps, allowing for precise control over the flow rate of liquids.

Fan control

VFDs are used to control the speed of fans, improving the efficiency of HVAC systems and reducing energy consumption. VFDs can also be used to turn on a fan when a certain temperature is reached, conversely, the fan would turn it off once that temperature decreases.

VFDs are versatile and essential components that ensure the efficient operation of electric motors in industrial processes, playing an important role in manufacturing, mining, oil and gas, water treatment, and other industries. By controlling the speed, torque, and direction of electric motors VFDs help to reduce energy consumption, increase efficiency, and ultimately result in significant cost savings for these industries. If you are looking to upgrade your industrial processes, consider incorporating VFDs into your operations for improved performance and cost savings.

Who uses Variable Frequency Drives?

Many industries rely on Motor Controls, particularly Variable Frequency Drives (VFDs), as vital components to regulate processes and systems, ensuring efficient and effective operations. Industries such as manufacturing, mining, oil and gas, and water treatment recognize the crucial role of controls in maintaining safety and productivity. Businesses and industries prioritize investing in high-quality controls to ensure smooth and efficient operations.

Manufacturing Industry

In the manufacturing sector, VFDs play a significant role in regulating the speed of conveyor belts, pumps, and other mechanical systems. VFDs control these components to save energy and optimize operations actively.

For instance, a VFD can actively adjust the conveyor belt speed based on the weight of the transported product. This active control prevents unnecessary energy expenditure during acceleration.

Controls are also actively employed in the manufacturing industry to manage and regulate the production process, ensuring optimal efficiency and effectiveness. Temperature, pressure, and other parameters can be actively monitored and adjusted, guaranteeing consistent, high-quality products.

Oil and Gas Industry

The oil and gas industry heavily relies on variable frequency drives (VFDs) to actively manage the speed of pumps, fans, and other machines involved in crude oil refining and processing. Active control of these systems reduces energy consumption and improves efficiency, resulting in significant cost savings for the industry.

Water Treatment Industry

The water treatment industry utilizes variable frequency drives (VFDs) to actively manage the speed of pumps and other mechanical systems essential for water treatment and distribution. By actively controlling the speed of these systems, VFDs reduce energy consumption, leading to cost savings for water treatment facilities. Additionally, VFDs ensure the quality of treated water by actively controlling the flow rate of chemicals and additives.

The Advantages of Using a VFD

There are several key benefits of using a VFD in an electrical system:

  1. VFDs allow for precise control of motor speed, which can result in improved efficiency and reduced energy consumption. This, in turn, can lead to lower operating costs and reduced environmental impact.
  2. VFDs can extend the lifespan of electric motors by reducing the stress on the motor and reducing the likelihood of motor failure.
  3. VFDs can improve the quality and consistency of products by providing precise control over motor speed and torque.

Contact us today to learn more about how motor controls can be used in your facility!