【Daily Question】Chemical Engineering Principles 288: Three-Phase Motors (January 8)
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This post was last edited by “Back to Cambridge” on January 13, 2016, at 16:36. Starting today, the Chemical Engineering Theory section is launching the “Question of the Day” activity, aimed at helping everyone reinforce their basic knowledge in chemical engineering. Subsequently, series such as “Fundamentals of Chemical Engineering”, “Mass Transfer and Separation”, “Chemical Thermodynamics”, and “Chemical Process Technology” will be introduced. We hope for your active participation! Wishing you all a Merry Christmas~~ For replies to the “Question of the Day” activity, answers can be viewed directly; however, the thread will be closed after one day! ! To encourage continued participation from everyone this year! You get 3 wealth rewards just for participating, and an additional 4 wealth points if you answer correctly~~~ Short answer question: How can one determine when a three-phase motor is operating on two phases? Answer: During the operation of a three-phase motor, if one of the phases is disconnected while the other two continue to operate, the imbalance between the phases causes the remaining two phases to operate under excessive current levels. In such a situation, the motor emits a humming noise and its speed decreases. If it continues to run, the motor’s windings will heat up, potentially leading to damage to the motor. If the ammeter is connected to the operating phase, the current will increase significantly at this time. When starting a three-phase motor with one phase already disconnected, the excessive starting torque causes the motor to emit a buzzing noise; its temperature rises rapidly, and in severe cases the motor can even be damaged.
How to determine if a three-phase motor is running on two phases? 1. The motor’s speed has decreased, and its sound is abnormal ； 2. The motor gets hot to the touch ； 3. The motor is prone to burning out if a load is connected.
1. The motor’s speed has decreased and its noise is abnormal. 2. The motor gets hot to the touch. 3. It is prone to burning out when under load.
1. The motor’s speed has decreased and its noise is abnormal. 2. The motor gets hot to the touch. 3. It is prone to burning out when under load.
1. The motor’s speed has decreased and its noise is abnormal. 2. The motor gets hot to the touch. 3. It is prone to burning out when under load.
How to determine if a three-phase motor is running on two phases? 1. The motor’s speed has decreased and its noise is abnormal. 2. The motor gets hot to the touch. 3. It is prone to burning out when under load.
1. The motor’s speed has decreased and its noise is abnormal. 2. The motor gets hot to the touch. 3. It is prone to burning out when under load.
1. The motor’s speed has decreased, and its sound is abnormal； 2. The motor gets hot to the touch ； 3. The motor is prone to burning out if a load is connected.
During the operation of a three-phase motor, if one of the phases breaks down while the other two continue to operate, the imbalance between the phases causes the remaining two phases to operate under excessive current levels. In such a situation, the motor emits a buzzing noise and its speed decreases. If it continues to operate, the motor’s windings will heat up, potentially leading to damage to the motor. If the ammeter is connected to the operating phase, the current will increase significantly at this time. When starting a three-phase motor with one phase already disconnected, the excessive starting torque causes the motor to emit a buzzing noise; its temperature rises rapidly, and in severe cases the motor can even be damaged.
1. The motor’s speed has decreased, and its sound is abnormal； 2. The motor gets hot to the touch ； 3. The motor is prone to burning out if a load is connected.
How to determine if a three-phase motor is running on two phases? 1. The motor’s speed has decreased and its noise is abnormal. 2. The motor gets hot to the touch. 3. It is prone to burning out when under load.