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Reversible Motor


 







Characteristic of Reversible Motor


    

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The reversible motor is a condenser type single-phase induction motor. Therefore, its general characteristics are as same as those of the induction motor.
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It is possible for the motor to operate in rotational direction from normal - stop - to reverse.
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The reversible motor has a temporary brake device built inside the motor to facilitate the operation in normal as well as reverse direction. Also, the mail and sub windings of the stator have their windings manufactured with the same method to guarantee the identical characteristics between them. Refer to (Fig. 2).
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Also, it has a higher starting torque to facilitate the frequent changes in rotational direction from normal direction to reverse direction, and vice versa, within a short time. Refer to (Fig. 3).
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The temporary brake is employed to prevent overrun. The temporary brake has a little retaining force to provide excellent instantaneous stop by preventing overrun when stopping. Refer to (Fig. 1).
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The changeover switch can help the motor reverse its rotational direction easily within a short time so that it is suitable for such operation that changes the rotational direction frequently from normal to reverse, and vice versa. Therefore, this motor is called a reversible motor.
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Since the design characteristic of the reversible motor is a capability to control the directional changes in rotation, the loss input is larger and the temperature can rise higher compared with the induction motor. Hence, the rated operating time is limited to 30 minutes.
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Thus, 30 minutes of rated operating time means that the motor at the rated load can have at least 30 minutes of non-stop operation within the safe upper limit of the temperature rise. It is possible for the motor at the intermittent load or at the light load to have non-stop operation, if only the outer cover temperature is not over 90