What Is The Soft Starter ?

The soft starter is a motor control device that integrates motor soft starting, soft stopping, light-load energy saving, and multiple protection functions. It not only enables the motor to start smoothly without impact throughout the entire starting process but also allows adjustment of parameters during the starting process, such as current limiting value and starting time, according to the characteristics of the motor load.

Soft starting technology is an emerging technology for controlling and starting motors. Nowadays, it has received extensive attention from modern people and is actively applied in enterprise production activities. This technology can smoothly start the motor, effectively reduce voltage, and perform compensation on the motor, thereby effectively reducing the adverse effects of motor starting on the power grid and related equipment, and thus effectively protecting various related equipment.

Main soft-start methods of the soft starter

1.Voltage ramp start

This starting method is the simplest for soft starter. It does not have current closed-loop control and only adjusts the thyristor conduction angle to increase it in a certain functional relationship with time. Its disadvantage is that due to the lack of current limiting during the motor starting process, a large impact current may sometimes be generated, which can damage the thyristor and have a significant impact on the power grid. In practice, it is rarely used.

2.Current limiting start

This starting method involves gradually increasing the starting current of the motor during the initial phase of startup. Once the current reaches a preset value, it remains constant until the startup is complete. During the startup process, the rate at which the current rises can be adjusted according to the motor load. A higher current rise rate results in greater starting torque and shorter startup time. This starting method is the most widely used, particularly suitable for starting fans and pump loads.