Today the VFD is perhaps the most common type of output or load for a control system. As applications are more complex the VFD has the capacity to control the acceleration of the engine, the direction the electric motor shaft is turning, the torque the motor provides to lots and any other engine parameter which can be sensed. These VFDs are also available in smaller sizes that are cost-effective and take up much less space.
The arrival of advanced microprocessors has allowed the VFD works as an extremely versatile device that not merely controls the speed of the engine, but protects against overcurrent during ramp-up and ramp-down conditions. Newer VFDs also provide ways of braking, power enhance during ramp-up, and a variety of settings during ramp-down. The biggest savings that the VFD provides is definitely that it can make sure that the electric motor doesn’t pull extreme current when it begins, so the overall demand aspect for the entire factory could be controlled to keep the domestic bill as low as possible. This feature by itself can provide payback in excess of the cost of the VFD in under one year after buy. It is important to keep in mind that with a normal motor starter, they will draw locked-rotor amperage (LRA) when they are beginning. When the locked-rotor amperage takes place across many motors in a manufacturing facility, it pushes the electric demand too high which often results in the plant having to pay a penalty for every one of the electricity consumed through the billing period. Because the penalty may be as much as 15% to 25%, the savings on a $30,000/month electric expenses can be utilized to justify the buy VFDs for practically every engine 
in the plant even if the application may not require operating at variable speed.
This usually limited the size of the motor that could be controlled by a frequency and they weren’t commonly used. The initial VFDs utilized linear amplifiers to regulate all areas of the VFD. Jumpers and dip switches were utilized provide ramp-up (acceleration) and ramp-down (deceleration) features by switching larger or smaller resistors into circuits with capacitors to produce different slopes.
We’ve learnt through lots of people who utilized Variable Speed Gear Motor and also are completely pleased.