Answer / raj anu raj

the valve will go to its fail safe position ie.. either
open or close

Answer / varathan

when communication failure occurs, Valve positioner have
three different action depend on application.
1. Fail to close
2. Fail to open
3. Fail to Standstill.(remain in the previous position)
Note: In automatic closed loop system, during failure
condition; controller must be forced back to manual mode
for safe operation

Answer / vijay singh

if profibus fails in operation.Valve positioner have
different action depend on application.
1.if valve is fail to open then valve will be in fully open
position
2.if valve is fail to close then valve will be in fully
close position.

Answer / ecxlsync

in an event of profibus failure or an absence of command signal, some valves will remain its current position, some will return to its safe position (fail safe).
There are valves designed to fully close (Fail to Close) or Fully Open (Fail to Open) in an event of failure.

Answer / jignesh parekh

during fail of profibus a valve be remain as it is. because
there is no command to travel a control valve move close or
open.

can anyone tell me about the basic concepts to consider before to start a PLC panel wiring

0 Answers   ABB,

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how the actually positioner of control valve working? where we gave 3-15psi pressure to I/P converter where it is firstly applied ?- on I/P to positioner then what happen? is control valve operate on 3-15 psi or its bench pressure?

2 Answers  

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How can we calibrate the level interface for Fisher® FIELDVUE® DLC3000?if use water to calibrate and our liquid SG are 0.75 and 1 ,Displacer height=14" and How much should be set SG in trasmitter during calibrate,for URV and LRV how shold be set

1 Answers  

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why orfice is not used for main steam flow calculation

0 Answers   OEG,

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what is the difference between impact plate n coriolis type solid flow meters n how they works....n which one is better

1 Answers  

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Can anyone say that formula of Converting the Diff. Pressure into Flow in Kg/Cm2 or any explaniation of Orifice Plate, Beta Ratio , How to calculate

1 Answers  

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what is meant by Hydroelectric powerplant?

0 Answers  

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Can we use twisted pair cable instead of ethernet for communication?

1 Answers   Yokogawa,

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Q- What are the application in which PNP transistor is preferred over NPN ?

0 Answers  

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what is scale factor of proximitor & unit of the vibration.

0 Answers   ADMA OPCO,

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WHICH INSTRUMENT USED TO CALIBRATE CONTROL VALVE?

8 Answers  

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what is control valve input and out put

10 Answers   Nirma,

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