The soft starter is a motor control device that combines soft start, soft stop, light load energy saving and multi-function protection. A starter motor that achieves no impact and smoothness throughout the start-up process, and various parameters such as current limit values and start-up times can be adjusted according to the characteristics of the motor load.
AST1 series Soft Starter
Soft Starter fills the gap between star-delta starters and frequency converters in terms of functional usability and price. With a soft starter, the motor voltage can be controlled to rise gradually during start-up, and the starting current is naturally controlled, which means that the motor can be started smoothly, mechanical and electrical stresses are minimized, and the soft starter is included The soft stop function effectively avoids the “water hammer effect” that occurs when the pump is stopped.
Soft starter main loop connection
The main function
1. Overload protection function: The soft starter introduces a current control loop, so it can track and detect the change of the motor current at any time. By increasing the setting of the overload current and the inverse time control mode, the overload protection function is realized, and when the motor is overloaded, the thyristor is turned off and an alarm signal is issued.
2. Phase loss protection function: When working, the soft starter detects the change of the three-phase line current at any time. Once the current breaks, the phase loss protection reaction can be made.
3. Overheat protection function: The temperature of the thyristor radiator is detected by the internal thermal relay of the soft starter. Once the temperature of the radiator exceeds the allowable value, the thyristor is automatically turned off and an alarm signal is issued.
4. Measurement loop parameter function: When the motor is working, the detector in the soft starter always monitors the running state of the motor, and sends the monitored parameters to the CPU for processing. The CPU analyzes, stores and displays the monitored parameters. Therefore, the motor soft starter also has the function of measuring the loop parameters.
5, other functions: through the combination of electronic circuits, can also achieve other kinds of interlock protection in the system.