Soft starter Advantages and Applications

Soft starters are used on high tension motors for the following advantageous features:

1. Smooth starting by torque control for gradual acceleration of the drive system thus preventing jerks and extending the life of mechanical components.
2. Reduction in starting current to achieve break-away, and to hold back the current during acceleration, to prevent mechanical, electrical, thermal weakening of the electrical equipment such as motors, cables, transformers & switch gear.
3. Enhancement of motor starting duty by reducing the temperature rise in stator windings and supply transformer.
4. The microprocessor version of the Soft starter has a soft ware controlled response at full speed which economizes energy, what ever may be the load. Because of the tendency to over specify the motor rated power, this feature has benefits for most installations- not only those where load is variable.
5. The power factor improvement is a self monitoring in built feature. When the motor is running at less than full load, the comparative reactive component of current drawn by the motor is unnecessarily high due to magnetizing and associated losses. Hence the voltage dependent losses are minimized with the load proportional active current component and as a result the power factor also improves simultaneously.

These are main applications of Soft starter:

• Steel industries (Rolling mills and processing lines)
• Cement industries
• Sugar plants
• Paper and pulp
• Rubber and plastic
• Textile industries
• Machine tool applications
• Power sector
• Water supply scheme
• And various process control applications…