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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how level can be measured in open tank with reference to pressure

1 Answers   Atul, INOX,

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WHAT REASEAN USE TRANSMETER TWO WIRE & FOUR WIRE

5 Answers   Kentz,

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how to calibrate temprature switch and flow switch ?

1 Answers   Adgas,

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A length of steel pipe is used to carry sea water to a desalination plant. An adequate corrosion allowance must be specified and indicated in the piping specification, which affects the _________________________ of the pipe

0 Answers  

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what is the difference between the microcontroller and PLC?

9 Answers   HAL, Havells,

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what is interlock system and why we use of this?

0 Answers  

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Need Intergraph softwares like SPI(INTOOLS),sp3d,PV ELITE, SP P&ID. CONTACT : logu.2211@gmail.com (8867825756)

0 Answers   GE,

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what is difference between positioner and position transmitter in control valve

2 Answers  

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we are used SAMSON 3730 Smart positioner.please tell me how to calibration this.

1 Answers   TCCL,

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1. What means HART communicator / where it is used / how to use it? 2. Types of Thermocouples and its temperature ranges / output of thermocouple? 3. Types of RTDs and its temperature ranges / output of RTD? 4. Idea about Temperature Transmitters? 5. Difference between Analog and Digital signals? 6. Difference between “2 wire” and “4 wire” system / instruments? 7. Difference between “Potential” and “Potential free” contact? 8. Types of flow meters / transmitters? 9. Types of level transmitters? 10. Difference between “Power/Control” cable and “Instrument” cable? 11. What means “shield” and “screen” in cables / how it is useful? 12. Draw a schematic of closed loop circuit of flow / level / pressure / temperature? 13. Idea about calibration of Control valve / positioned / I/P? 14. How to bypass a digital/analog signal in PLC/DCS by hardwire and software?

6 Answers   JSL,

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In a gas over oil actuator, after the opening/closing of valve, how the gas is vented out? How does the hydraulic/gas circuit function?

0 Answers   Reliance,

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