Soft Start Drives
 by The Three Phase Electricity Specialist

	Soft Start Drives Home
	Soft Start Drives What are the advantages of soft start drives?  Can they prevent damage to motors during startup?  Are soft start drives more economical?  Read more.
	Variable Frequency Drives Variable frequency drives vary the production speed of motors.  What are their advantages over soft start drives?  Are they more costly than other drives?  Read more.
	What is the difference between a Variable Frequency Drive and a Soft Start Drive? How does a variable frequency drive differ in regulating speed of a motor versus a soft start drive?  When is it more beneficial to have a variable frequency drive?  What are the benefits of using a soft start drive instead of a VFD?  Read more.
	Applications of Soft Start Drives Some of the applications that soft start drives are used for are pumps, fans, stirrers, mixers, driers, cutting machines and rotating filters.  Read more.
	AC Drive Guidelines Technical information on AC drives and how they work. Many of the AC drives seem to perform the same, but the objective of this article is to provide technical information to understand the differences.  Read more.
	Inverter Drives Inverters are used when DC power from batteries, solar panels or fuel cells need to be converted to AC power.  Inverters are used for small applications such as switching power supplies in computers to large applications such as electric utility operations. Read more.
	TEMCo Soft Start Drives TEMCo offers a large selection of soft start drives.  With their large inventory, they can ship nationwide and internationally immediately after your order is placed.  TEMCo only sells high quality products, which provide many years of excellent service for your application requirements. Read more.

Soft Start Drives

An AC motor, when turned on, will try to reach its nominal speed as quickly as possible.  It will draw maximum current from the power supply and also apply maximum torque to the motor.  This can be a problem for many applications.  Applications like conveyers, pumps, and band saws must be started slowly and sometimes stopped slowly to prevent mechanical shocks such as water hammer, and strains on bands, couplings and shafts.  These applications usually involve a great deal of inertia.  Sudden starts can damage the motor as well as other equipment, plus diminish system performance.


A Soft Start Drive is a device that regulates the voltage to a motor.  It starts the motor at a lower voltage and slowly ramps the motor up to operation voltage.  There has been a dramatic increase in the use of soft start drives because they reduce wear and tear on motors and their drive systems, which results in lower maintenance and the conservation of energy.  Soft start drives play a significant part in improving plant performance and lowering operating costs.


Soft Start Drives have many applications such as escalators, pumps, elevators and conveyor belts.  They all operate more effectively if they are soft started. Depending on their applications, soft start drives can be used to control voltage in various ways.  Some equipment or motors require a non-linear acceleration, and the voltage ramp is, therefore, related to the actual current drawn.  A number of applications require a kick-start torque for a brief period of time followed by a soft ramp-up acceleration.  Or in the case of a band saw, it usually requires a quick stop function provided by a DC brake.  Soft start drives cover all these applications plus many more. For more information on soft start drives and the different makes and models, we recommend visiting the Variable Frequency Drive Website to give you more insight on soft start drives.


You could use an autotransformer, which does reduce start current and also allows some control over the level of start current.  However, they do not eliminate the risk of a jump in torque when shifting voltage like the soft start drives does.

WEG and Baldor have been manufacturing motors and drives for many years, and both of these companies manufacture high-quality soft start drives.  TEMCo, who is a leading distributor for WEG and Baldor Soft Start Drives, has an excellent technical and engineering staff that can help you select the right soft start drive for your equipment.  TEMCo Tower Electric Company’s reputation for excellence will save you money, and your equipment will provide you with many years for quality service.  For all your AC drives needs, call TEMCo at 512-490-2187 or toll free at 1-800-613-2290.

The Three Phase Electricity Specialist strongly recommends using reputable manufacturers when purchasing soft start drives and other electrical products.  Please read all our educational articles provided in our Soft Start Drive website.

Soft Start Drives start motors at lower voltages, slowly ramping up to operation voltage, which reduces wear on mechanical gears, chains, sprockets, belts and gearboxes.
 

Soft Start Drives eliminate motor over-fluxing and allow under-loaded or oversized motors to operate more efficiently.
 

Baldor Electric Company
Baldor is a U.S. based company and is a leading manufacturer of industrial electric motors, drives, power transmission products and generators.
 

Weg Electric Motor Company
Weg has been in business since 1961 and is a reputable manufacturer of soft start drives and electric motors.  They distribute high quality products worldwide.
 

The leading manufacturers will offer quick nationwide and international shipping from regional warehouses.