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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i have an interview in Qatar Petroleum. So please provide the all details abt fire & gas systems

1 Answers   Qatar Petroleums,

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What is Alpha & Beta fctors related to Orifice Plate & its relation with flow?

0 Answers  

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why we use 0.2 to 1.0 kg/cm2 output in control valve

4 Answers   GNFC,

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What is the detail function of I/O card in DCS ? Why we dont use the I/O directly with controller?

3 Answers   Kekran Mekran, TCE,

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kindly sent some demo question and answer

0 Answers   HPCL,

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what is the working principal of pribe

0 Answers  

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how to rectify the poor signal strength in utrasonic digtial flow meter ,model:ge digital xce868i

0 Answers   KNPC,

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open tank and close tank leavel transmiter about range and calibration

0 Answers  

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why we use impulse line of flow transmitter at 45 deg. angle both side of orifice plate.

0 Answers  

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what is full form of NAK?

1 Answers  

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Why the tapping connections are taking above for gas service and below for liquid service?

2 Answers   ADCO,

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