Answer / s.p. patel

control valve is control through pneumatic and electrically like that positioner and i/p converter but mov control through only electrical and different types cards use mov use in generally large pipe line size mov means motorized operating valve

Answer / aamir

1-one reason of using MOV instead of control valve is that "MOv has low pressure drop then control valve"
2-Mov are useing electrical power supply. so no need or pneumatic or extra supply.at some places we can not provide pneumatic supply to control due to long distance,so we use MOV.

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