Answer / karthikeyan

if you open the inlet of afr, valve ramains in open condition only, bcoz afr hold the output air pressure until u drain from regulator. and you are telling that while you are going to open the inlet of air regulator your valve is in open position, that means there should be air in outlet of regulator. bcoz your valve is air to open valve. if there is no air it should be in close condition.

Answer / mallu byali

AFR DOES NOT HOLD THE PRESSURE, IT IS ONLY REGULATE THE
PRESSURE AS YOUR DESIRED SET POINT OR WE HAVE TO SET THE
PRESSURE FOR OPERATING THE VALVE DEPENDS UPON ITS ACTUATOR
CAPACITY..

Answer / girish.bashyam

Regulator is just for regulating the air supply . this air
supply will be regulated as per the name plate detail of
control valve. the output of AFR will go to positioner and
its output will go to diaphragm. Depends on the mA the
flapper will be moving and accordindly the output of
positioner will vary its outputis connected to diaphragm
which will move from 0 to 100% respective of the command.due
to flapper movenment the required air to move the diaphragm
only provide to diaphragm for its movenment.

Answer / sandeep modi

If you open the inlet of air regulator,no pressure will hold
at air regulator,the pressure will go to zero and your air
to open valve will close.

But when you stop the supply of inlet air(not open the
supply) the pressure of AFR will be hold at that
condition,and if you valve is in open condition ,it will
remain open.

capillary type tranmitter using remote seals and capillary tubes filled with liquid of known of known density so if you wanna callibrate it just close block valve just before capilary @ high side & connect druck apply it's calibrated range pressure as normal calibration ensure low side block valve must be closed & if you asking commissioning so this is not a DP type pressure tx so simple if you wanna put in servie this tx just open high side block valve & than low side block same way i do it but still transmitter showing -13 ma.just tell me what i want to do ?

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