Answer / elham

Hi
No we must not use MOV instead of ESDV. As you know MOV's are working with power but ESDV's are working with Instrument Air (closing and opening) so in the case of power outage we can't close or open MOV but in the case of IA outage we can adjust ESDV on fail safe mode. so ESDV's that should work on emergency cases always are reliable with IA.

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