Why we are using 4-20 mA as Analog signal transmission other than 3 to 19 or 2 to 18 or 6 to 22 like wise ? What is the reason behind using 4 & 20 mA? Can anyone give proper technical reply ?

5 Answers   Air Liquide,

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For an Instrumentation Engineer, is there any effect on Instruments of safety zones like zone0, zone1, zone2. As an instrumentation Engineer, what we have to consider or remember while working in these areas.( zones 0,1,2).

1 Answers  

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what is the difference between PLC & DCS

17 Answers   L&T,

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Hi, am aniket, I got engineering degree in instrumentation and control, but as their were no job availabilities for engineer's post I started working as instrumentation technician I kuwait, so my question is is this technician's experience worth for getting the position of engineer?

1 Answers   Almeer Technical Services,

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What is the difference between uv and ir scanners? and what is the workig principle of both

0 Answers  

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what is the input of digital counter during the the calibration time?

0 Answers  

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So I'm a first year apprentice and I'm having a tough time with knowing the difference between AI, AO, DI, DO. I'm having a hard time understanding what devices are which and why. Can someone explain this to me?

2 Answers  

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How to calibrate level transmitter with use of HART?

0 Answers   Samsung,

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how to calibrate a control valve?

7 Answers   Reliance, Telecon Systems,

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how far the two wire transmission (loop power) maximum distance suitable?

2 Answers   PCIL,

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Can any body give detail about orifice sizing?

5 Answers   Essar,

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which type inter lock use in petrochemical refinery,and oil & gas?

0 Answers  

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