Answer / sumith

PID control valves works on 4-20 ma ,plc gives 4-20 ma to
pid valve according to the difference between setpoint and
actual value (for e.g s.p temp = 90 degc actual = 30
degc)now plc will give 20ma to pid valve for temp to reach
the setpoint.pid valve should have continous air supply.
to calibrate pid valve there is span and zero adjustment.

pid tuning is done in plc not in valve.pid tuning in plc is
trial and error type tuning.
we have to some values in P and I and D and check whether it
is reaching the setpoint smoothly

which one is best profibus or RS485 for communication?

2 Answers   Honeywell,

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We Have Two Field bus Pressure Transmitters of Different Sensor Range (I.E One is of Lower range and Another is of Higher Range).Is same Process Line. My Question is Can i provide Saturation Limit to my field Bus Transmitter as We can provide Saturation current limit to HART Instruments. As During Low Pressure Both Working OK ,But During High Pressure, transmitter with Lower sensor range Goes to Fault mode as Beyond its Sensor Limit it can Measure, So may I provide Saturation point Some where to Suppress This Fault during High Pressure.

0 Answers   OPaL,

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What is the syllabus for Instrumentation Engineers, who wish to join the Public Sector Units??

1 Answers  

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calibration of instruments.

11 Answers   ONGC,

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what is the process for double acting cylinder pneumatic for 32' v/v

0 Answers  

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any body please send me the old question papers of ongc test.

0 Answers   NTPC,

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Define all the process Variable and state their unit of measurement. ?

0 Answers  

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what is the calibration standard for pressure and differential pressure transmitters?

1 Answers   Thermax,

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how micro-processor and micro controller different from architecture

3 Answers   Bhushan Power Steel,

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how to calibrate ph meter?

3 Answers  

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If i have 4 Allen Bradely make RS logix 5000 PLC and for viewing that we are using 4 RS view SCADA for 4 different packages. Now, I will want to view two packages on only one SCADA. Then how i will do it?

0 Answers   Essar, Reliance,

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WHAT IS TSI? HOW ITS WORK

2 Answers  

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