How many motor starters are required for a part-winding starter setup?

In a part-winding starter setup, two motor starters are utilized to effectively manage the starting process of a 3-phase induction motor with dual winding configurations. This methodology is specifically designed for large motors that benefit from a reduced starting current and torque.

The two starters operate as follows: one controls the initial winding that supplies power to the motor at startup, allowing the motor to reach a certain speed under reduced load. After achieving this initial speed, the second starter is engaged to activate the additional winding, bringing the motor to full operational capacity. This staggered starting technique not only minimizes electrical stress on the system but also enhances the mechanical performance of the motor during startup conditions.

This approach is particularly useful for applications where soft starting is essential, and where controlling the inrush current to prevent damage and excessive wear on the motor and connected components is a priority. Other options, such as a single starter, would not effectively manage this dual-winding operation, while three or four starters would exceed the requirements and complicate circuit management for standard part-winding starter configurations.