Answer / me

The third most common flowmeter behind differential pressure
and positive displacement flow meters, is the magnetic flow
meter, also technically an electromagnetic flow meter or
more commonly just called a mag meter. A magnetic field is
applied to the metering tube, which results in a potential
difference proportional to the flow velocity perpendicular
to the flux lines. The physical principle at work is
electromagnetic induction. The magnetic flow meter requires
a conducting fluid, for example, water that contains ions,
and an electrical insulating pipe surface, for example, a
rubber-lined steel tube.
Usually electrochemical and other effects at the electrodes
make the potential difference drift up and down, making it
hard to determine the fluid flow induced potential
difference. To mitigate this, the magnetic field is
constantly reversed, cancelling out the static potential
difference. This however impedes the use of permanent
magnets for magnetic flowmeters.

difference between DCS @ SCADA system? and how can use in field

5 Answers   Marafiq,

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what is the difference between mmhg & mmwc?. i want to calibrate a transmitter in the range of -100 to 300 mmwc. Which is the reference for calibrate the Tx,if mmwc not available?. Is it mmhg or mmho2?.

3 Answers   UPL,

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In split range control, we will control 2 outputs with time interval. Eg :(with 4-20 ma signal, for 4-12 ma we are operating one control instrument like valve & for 12-20ma we are operating other control instrumet (other valve). If we get a signal of 15ma to first instrument (Valve 1), what will happened to the first valve, and if we get signal above 20 ma to 2 valve what will happened ?

3 Answers  

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

0 Answers   BRML, ONGC,

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p=hdg,please explain these parameters?

7 Answers  

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Explain why plc require in analog input 4-20amp & 0-10 volt?

0 Answers  

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State four different types of flow measurement.

4 Answers   ADMA OPCO,

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1 Answers   Sirpur Paper Mill,

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1.what is controller proportional gain 2.what is the controller intergral action time. 3.A proportional plus derivative controller that has a proportional band of 20% and a derivative action time of 0.1 minutes. Construct the shape of the output waveform for the triangular input if the input rises and falls at the rate of 4 units per minute.

0 Answers  

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what is intrument termination what is commisioning

3 Answers  

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sir ,iam in dem urgent need of HPCL Paper of Instrumentation Branch plz send me at your earliest convenience at ujjwal_sharma1983@yahoo.com

0 Answers   ONGC,

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what is the difference between single and double compression cable gland

3 Answers   Petrofac,

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