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

8 Answers   Emerson, IEM,

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dear sir we have insatlled positioner model no.sipart PS2 make Siemens at our control valves . now problem is if we want to increase the response of valve opening speedy /fast. what parameters do we change for positioner ? any idea. please guide us.

0 Answers   CPL,

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how many type of control valve?

10 Answers  

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what is the working principle of vortex flowmeter

9 Answers   Essar,

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What is the main difference between Cavitation and Flashing?

1 Answers  

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

0 Answers  

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radial & axial vibration sensor output voltage is ac or dc volt?

8 Answers   Vedanta, Voltech,

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What are the uses of orifice plates?

0 Answers  

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1- Explain about HPM 2- What is the FSC and explain the configuration of FSC 3- explain the complete loop of vibration, how it works (field to control room) 4- What is the use of proxymitter? 5- During job your partner effected with H2S then what you have to do. 6- what type of gland packing uses when valve glind is leaking.

0 Answers  

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instrumentation

1 Answers   Tata Steel Limited,

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it is possible to check the fail safe condition in pressure transmitter. if possible how?

0 Answers  

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canu tell me why 4-20 ma and why not this 3-25ma?please give reason of this value.

6 Answers  

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