first? 5. In the control circuit shown in Figure 31-2, if an overload occurs on any motor, all three motors will stop running. Using a separate sheet of paper, redesign the circuit so that the motors must still start in sequence from I to 3, but an overload on any motor will stop only that motor. If an overload should occur on motor 1, for example, motors 2 and 3 would continue to operate.

first? 5. In the control circuit shown in Figure 31-2, if an overload occurs on any motor, all three motors will stop running. Using a separate sheet of paper, redesign the circuit so that the motors must still start in sequence from I to 3, but an overload on any motor will stop only that motor. If an overload should occur on motor 1, for example, motors 2 and 3 would continue to operate.

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter37: Automatic Speed Control For Wound Rotor Motors

Section: Chapter Questions

Problem 3SQ

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There are 2 1000Watt 3-phase asynchronous motors in a Walnut Cracking machine (it is desirable to operate the motors in a way that they remain in star connection). When the "Start" button is pressed, the 1st engine will start immediately, 3 seconds after the 1st engine starts, the 2nd engine will also start. After the two engines work together for 4 seconds, the 1st engine will stop, the 2nd engine will start and stop for another 10 seconds. If the "Stop" button is pressed at any stage of the operations, the motors will stop. The rotation directions of the motors are required to be opposite to each other. Draw the necessary power and control circuit.
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