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ADVANTAGES OF MAGNETIC CONTROL OF MACHINES

Having discussed the starting and stopping of a motor by using control devices like push buttons, contactors and over-load relays, we are in a position to discuss the advantages of magnetic control over the manual control. The various advantages are listed as follows:

1) Magnetic control permits installation of power contacts close to motor whereas the actuating control device i.e., a push button switch could be located away from the motor in a position most convenient to the operator.

2) Magnetic control provides safety to the operator as remote operation described above minimizes the danger to the operator of coming into accidental contact with live parts or being exposed to power arc and flashes at the main contacts.
3) The most important advantage of magnetic control is the elimination of dependence on operators’ skill for control of motor performance. Current and torque peaks could be limited thus resulting in less wear and less maintenance.

4) Magnetic control also makes interlocking (to be discussed later) between various operations of a multi motor drive easy. The various operations can be performed in the desired sequence automatically.

5) With the demand for more production in industry, it became necessary to atomize the machinery to meet the challenge. Today in our industrial plants most of the machines are automatic. Once the machine is started most of the operations are carried out automatically.

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