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.

as an instrumentation engineer which are the things we have to know / or we must have idea about that....

2 Answers  

---

why we should maintain neutral earth voltage below 1V while calibration? why cant it be 1.2V or 2V

0 Answers   Hospira,

---

how many maximum enter 2mm Dia solid cylindrical pipe into 8mm Dia hollow cylindrical pipe. give answer with calculation.

0 Answers  

---

steam drum level transmitter calibration procedure? with example?

1 Answers  

---

How d.p. Transmitter can be applied to open tank?

0 Answers  

---

How can i copy program (parameter) from mm440 (V.F.D.) by using BOP?

0 Answers  

---

if my flow is 20000 m3/h than which range of DPT i have to use????

0 Answers  

---

In close vessel/ drum why we use d.p. transmitter of -ve range i.e. (-)500 to 0 mmwc.

2 Answers   IMECO, Voltech,

---

how can you change unit of totalizer in siemens mag 5000 flow meter?

2 Answers   PowerTech,

---

I have installed a RTD whose length is 2250mm(RTD stem length), but it's upper 200 -250mm is out of the reactor, and this upper 200mm stem is surrounded by atmospheric temp. And the lower portion i.e. 2000mm is in contact with the measuring fluid, then does the final measuring temp. Gonna change as the upper 200mm RTD stem is out of reactor?

1 Answers   Process Control Technologies,

---

what is AWG?

2 Answers   NTPC,

---

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 ?

1 Answers   Indian Steel,

---