Question 316Electricity/Electronics - QMED70% to pass
What is the primary functional purpose of the KM1 contactor as shown in the illustration? Illustration EL-0080
AI Explanation
The correct answer is B) connects the autotransformer in "wye" configuration while in the start mode.
The KM1 contactor is used to connect the autotransformer in a "wye" configuration during the motor's starting sequence. This allows the motor to draw a reduced current from the power supply, limiting the initial inrush of current and easing the strain on the electrical system. Once the motor reaches the desired speed, the KM1 contactor opens, and the motor is connected directly to the line voltage (across the line) in the run mode.
The other options are incorrect because they do not accurately describe the primary function of the KM1 contactor in this application. Option A, C, and D do not correctly identify the contactor's role in connecting the autotransformer during the starting sequence.
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