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

5 Answers  

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what is the difference between profibus and controlnet networking.

0 Answers   HZL,

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Hi..i am B.E. (elect.&comm.)..i m workini in a bio mass power plant as inst. Engg. I want 2 know about growth in big power plant sector..is this field is good 4 me ..i m electronics engg..? Plz plz reply..

2 Answers   Reliance,

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What is mean by AC voltage and DC voltage

2 Answers  

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can u please give the exact ckt explaination of AC Drive related to industries.

6 Answers  

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How to measure high frequency using thermistor

1 Answers   DRDO,

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Which standard is used for calibration of Control Valves ?

2 Answers  

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What is rang ability?

0 Answers  

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How can i copy program (parameter) from mm440 (V.F.D.) by using BOP?

0 Answers  

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Conversions

0 Answers   CCIE, Nestle,

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can you provide me full detail about instrumentation in ONGC??

0 Answers   BRML, ONGC,

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what is Instrument Schedule, and what it is mainly used for?

0 Answers  

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