Answer / rajkumar

please visit

http://library.abb.com/global/scot/scot296.nsf/veritydisplay/3cf6fd6285bb243bc1256bc200600cb6/$File/3BDD013039R0001_A_en_Maestro_UX_Overview_(04_02).pdf

Why any transmitter signal is 4-20 mA only Why is started from lower range 4 mA and upper range is 20mA.

5 Answers   Edac,

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how to convert bar to mA?

1 Answers  

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what is the name of thermocople element cable from field to pannel end?

3 Answers  

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wht is mean by dpt(differential pressure transmitter)

1 Answers  

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what is the full formof HART

7 Answers  

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can we connect instrument earth pit to electrical earth pit, if not why?

2 Answers  

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whats the abbreviation of IOP? is it instrument of power or input open problem?

1 Answers  

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generally transmitter power supply having some range(12v to 35v) but the out put(4-20 mA) must same for given input.If we vary the power supply voltage then output mA also to be change according to V=IR. Is there any voltage regulator in the transmitter ?

2 Answers  

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1 bar is equal to how many pound per square inch(psi)?

14 Answers   Essar,

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what is function of switch, and how is it work, explain with difination

1 Answers   Bapco Bahrain Petroleum Company,

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WHAT IS A SYMPTOM OF FAULT WITH THE SPAN OF AN INSTRUMENT? 1)ZERO-POINT AND 100% ARE CORRECT BUT NOT A MID-RANGE. 2)ZERO-POINT IS CORRECT ,BUT 1005 INPUT IS NOT GIVING 100% OUTPUT. 3)LINEARITY PRBS. 4)1005 O/p IS CORRECT BUT ZEO POINT IS WRONG.

1 Answers   Reliance,

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How can we say that accuracy of measurement increases by using 3 or 4 wire RTD? because for example: If resistance of RTD element is say r ohms and Resistance of the cable from transmitter to RTD is R ohms And if 4 wire RTD is used, ____._____________________ R ohms | |_____._____________________ R ohms / \ / r ohms \ \ | |______.__________________ R Ohms | |_______._________________ R ohms Then the actual resistance measured will be: Total = r + R/2 + R/2 = r +R Ohms Note: r+R instead of r ohms. hence error

2 Answers  

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