in instrumentation why we are using 4-20mA , why not voltage ? if somebody design a instrument which works on voltage then can we use that instrument?

6 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 conversion factor for nm3 to kg/hr in air flow

4 Answers  

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how we calculate error in percentage when instrument calibrat

1 Answers  

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Watt is Wrms define rms?

2 Answers  

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

0 Answers   NTPC,

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How the warning lamp of a charging-system is activated ?

0 Answers  

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On liquid service if PT Head is 18 meters. How much pressure will be exerted on it. If Transmitter is not in service?

1 Answers  

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what is plc? breif explain

3 Answers   APL,

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HOW TO CONVERT 0-60KG/CM2 PRESSURE TRANSMITTER TO A LEVEL TRANSMITTER? CAN WE ABLE TO DO IT? IF YES HOW TO DO IT BY USING HART?

3 Answers  

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The DCS stand for________________________. it is composed of the following major components: a:______________ b:______________ c:______________ d:______________

2 Answers  

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What is sensitivity in vibration probes..?

0 Answers   Lanco,

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