Question 304Electricity & Electronics - Assistant Engineer

70% to pass

You are reconnecting a three-phase induction motor to the supply line. To prevent possible damage to the load, due to the wrong direction of rotation, what should be done?

Acheck the supply line phase sequence and motor rotation with appropriate indicators, then connect correspondingly marked leads
Bconnect the motor and then use the 'jog' button to determine the direction of rotation
Cconnect the phase indicator to the motor leads, rotate the motor by hand and then connect to the supply voltage
Dconnect the phase indicator to the supply voltage then connect the motor
AI Explanation

The correct answer is A) check the supply line phase sequence and motor rotation with appropriate indicators, then connect correspondingly marked leads. This is the correct answer because it is important to ensure the proper rotation of the motor to prevent possible damage to the load. Checking the supply line phase sequence and motor rotation with appropriate indicators, then connecting the correspondingly marked leads, ensures the motor will rotate in the correct direction. This is a standard procedure recommended to prevent issues when reconnecting a three-phase induction motor. The other options are incorrect because they do not adequately address the need to verify the phase sequence and motor rotation before making the connections. Options B, C, and D do not provide a reliable method for determining the proper phase sequence and rotation direction prior to connecting the motor.

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