why we use 4-20 mA to do calibration of the instruments.why we cant use 0-20 mA?

8 Answers   Emerson, IEM,

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temptrure me ketne frequiency hote hai

0 Answers   ME,

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How to calibrate a orifice differential pressure flow transmitter in process?

1 Answers  

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in a electronic controller why we are using 250 ohm resistance in input signal?is i/p is necessary in control valve when we are using electronic controller give details?

3 Answers   IOCL,

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During valve sizing from all calculation you got flow coefficient CV 12,than what it means? like for selecting pressure transmitter if your MAWP is 12 bar than you select a capsule of max. 20 bar which cover your mawp 12 in same way for selecting control valve If CV is 12 than how we use it in selecting valve??????

1 Answers  

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kindly sent some demo question and answer

0 Answers   HPCL,

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what is diff between the motor and pump

10 Answers   HCL,

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What are the charecterstics of control valve.

2 Answers  

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what happens if we are having very very high cavity and flashing in a control valve..??? is it stops working...immediately... or eroded...slowly

2 Answers  

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What are the different modes of a contollogix family processor? How they work?

3 Answers   Honeywell, Siemens,

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What FLOW METER generally used in Gas plant?

5 Answers   Gasco,

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difference between span and range

3 Answers   IOCL,

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