What is the maximum current load that each motor starter in a part winding starter can handle during normal operation?

In a part winding starter configuration, the design allows for the motor to be started in two phases. During the initial start-up, only a portion of the motor windings is energized, which reduces the inrush current. Specifically, each motor starter in this setup is sized to handle one-half of the full load current (FLC) of the motor. This is crucial because it ensures that the motor can handle the start-up conditions without exceeding the current rating of the starter.

When a motor is started, it experiences a high inrush current which can be multiple times its normal operating current. By utilizing a part winding starter and energizing only half of the motor's windings, the current load is effectively limited to one-half of the FLC. This strategy is beneficial for both the electrical components due to lower stress and for the motor itself, minimizing the risk of damage during start-up.

Understanding this principle is essential for ensuring that the motor and its control system operate efficiently and safely without overheating or tripping the starter due to excessive current during start-up.