Soft starter unit is a controller with 6 thyristors used for torque-controlled soft starting and stopping of three-phase squirrel cage asynchronous motors, for power ratings between 4 and 900 kW. It offers soft starting and deceleration functions along with machine and motor protection functions, as well as functions for communicating with control systems. These functions are designed for use in the most common applications for centrifugal machines, pumps, fans, compressors and conveyors, which are primarily to be found in the construction, food and beverage and chemical industries.