Device that changes the direction of single phase ac motor?

[srinaath]

hi alll...we know that by changing the polarity of phase and neutral , direction of ac motor can be changed. but is there any automated device that does this job? ...

 

[collinsmark]

hi alll...we know that by changing the polarity of phase and neutral , direction of ac motor can be changed. but is there any automated device that does this job? ...

That's not quite right.

Merely reversing the phase and neutral is not enough to change the rotation of the motor. You can prove this to yourself if you are in a country with 120 V outlets and have an old fan that was made before there was a differentiation between the "hot" and neutral in the plug. In such a situation, just unplug the fan, turn the plug 180 degrees and plug it back in. The fan will still work just as it did before. Rotating the plug makes no difference in the fan's operation.

If you want to reverse the direction of the single phase AC motor, you'll have to modify the motor's starting coils' circuitry.

https://woodgears.ca/motors/reversing.html