company news

How to get the most out of a soft starter
Electric machinery and equipment must be in line with the products in order to exert the greatest effect. The performance of these products and equipment control are inseparable, so why can these machinery and equipment have better use through soft starters?


In practical applications, three-phase asynchronous motors are the most commonly used in traditional engineering. In many cases, these motors cannot be connected directly to the power system due to their starting characteristics. If started directly online, there will be an inrush current 6 times the rated current of the motor, which can overload the power supply system and series switchgear.


When using the soft starter equipment, if it is started directly, it will also generate a high peak torque, which not only has an impact on the drive motor, but also loads the mechanical device. For example, auxiliary power transmission components. In order to reduce the starting current, starting aids, such as starting reactors or autotransformers, should be used. However, this method can only gradually reduce the voltage, while the soft starter can achieve a shock-free start by smoothly increasing the terminal voltage. It can best protect the power system and the motor.
At the same time, the soft starter can realize soft stop. Its process is opposite to the starting process. After the thyristor receives the stop command, the conduction angle gradually decreases from full conduction, and it transitions to the process of full shutdown after a certain period of time. The parking time can be adjusted from 0 to 120s according to actual needs. When the motor stops, the traditional control method is completed by instantaneous power failure.


But there are many applications where instantaneous shutdown of the motor is not allowed. For example, if the pump system of high-rise buildings and buildings is stopped instantaneously, it will produce a huge "water hammer" effect, which will damage the pipeline and even the pump. In order to reduce and prevent the "water hammer" effect, the motor needs to be stopped gradually, that is, soft stop. The use of a soft starter can meet this requirement. In the pumping station, the application of soft parking technology can avoid the "slamming door" damage of the pumping station, and reduce the maintenance cost and workload.