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?
• Phase sequence of a three‑phase supply and its effect on motor rotation direction • How a phase rotation (sequence) indicator is used on both the supply and the motor leads • Why you must be certain of direction of rotation before full connection under load to avoid damage
• Which option makes you verify both the supply’s phase sequence AND how the motor will rotate before you finally tie the motor leads into the line? • Which methods rely on indicators and markings (systematic and repeatable), and which rely on trial‑and‑error with the motor actually running? • On a ship, which procedure would be considered safest and most professional when reconnecting a critical three‑phase load?
• Make sure the method does not require running the motor at normal conditions without first knowing its rotation direction • Confirm that the procedure uses a proper phase‑sequence/rotation indicator, not just visual guessing or hand‑rotation • Check whether the steps include matching marked motor leads to the known phase order of the supply before energizing the motor on load
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