What's the Principle of operation of
Electromagnetic Flow Meter
?
The
functioning of these meters is based on Faraday?ˉs Second Law of
Electromagnetic Induction. It states that, a conductor moving inside a
magnetic field with the path of its motion perpendicular towards the
magnetic field generates an EMF across it plus the path on the EMF is
perpendicular to each, the magnetic field along with the path of motion.
The generated EMF is proportional towards the magnetic flux density, B,
the velocity of conductor v plus the length from the conductor l.
Within the flow meter the magnetic field is generated by fascinating the
coils plus the conductor is definitely the liquid itself, below
measurement with all the length equal for the diameter of pipe.
As a result EMF = B.v.d, where d would be the diameter in the inner wall of flow meter
What is the degree of conductivity expected for the liquid beneath measurement to acquire satisfactory operation of the meter?
In
general the electrical conductivity of liquid beneath measurement
should really have minimum of five micro siemens per cm. conductivity.
But very carefully created transmitters and main flow sensors, like
Manas, can measure flow rate of liquids getting conductivity as low as 1
micro siemens per cm.
Can Electromagnetic Flow meter be
employed for measurement of flow of liquids like Petrol, Diesel,
Kerosene, and A variety of varieties of oil, Edible oil or other organic
solvents?
As explained in query 2 above, the essential
conductivity of liquid is at least 1 micro siemens per cm. The
conductivity of liquids below query are nearing to pretty much zero.
E.g. the conductivity of kerosene is in Pico Siemens, exactly where even
cautiously designed meters also cannot measure the liquid flow.
Can the Electromagnetic flow meter measure the flow of fluids like, steam, air, gases or any such compressible fluid?
Electromagnetic flow meters are designed as Liquid Flow Meters. They cannot measure flow rates of compressible fluids.
Can Electromagnetic Flow Meter be employed for measurement of Mass Flow Rate?
If we refer to question no.1 above we discover the fundamental equation as,
E = B .v. d
Exactly
where E is definitely the Electro Motive Force generated within the
liquid due to its typical velocity. It is actually clear that to get a
provided flow meter the magnetic flux density and diameter are
continuous. The EMF is hence proportional to only typical velocity of
the liquid. Velocity when multiplied by cross sectional area provides us
volumetric flow rate.
The electromagnetic flow meters are therefore volumetric flow meters and cannot be applied as Mass Flow Meters.
If
the density from the flowing liquid is fixed and if there is a facility
to feed the density in transmitter the E.M. Meter is usually used as a
Mass Flow Meter
What's the typical Accuracy of measurement for Electromagnetic Flow Meters?
The
common accuracy of those meters is +/- 0.three % of reading. The
specified accuracy is +/- 0.5% of reading among 10 % to 100 % of
calibrated flow price range.
What's meant by Complete Bore Meter ?
A
Complete Bore meter is actually a circular meter exactly where, when
the flow passes by filling the entire bore area, the meter can measure
the typical velocity inside the meter. Naturally the accuracy of a
complete bore meter is often much greater than any other form.
What is the distinction involving Insertion Variety and Full Bore Variety meter?
As
explained in question 7 above the complete Bore Meter measures the
typical velocity. The Insertion Variety measures velocity at only one
particular point. So in actual fact Insertion Meters are velocity meters
and not genuine flow meters. Naturally the accuracy of Insertion form,
if utilized as flow meter, is quite poor.
What's the effect of modify in velocity profile through the meter, on accuracy?
Provided
that the velocity profile is symmetrical around the axis there's no
impact on accuracy with change in velocity profile, e.g. from laminar to
turbulent or perhaps transitional profile of velocity.
What's the minimum velocity for which the Electromagnetic Flow Meter performs with consistent readings?
General
objective meter manufacturers do not recommend to operate their meters
beneath 0.two to 0.three meters/second velocity. Manas make meters,
SROAT 1000plus and converter SROAT 1000 A, can comfortably be made use
of for velocities as low as 0.1 meters/second.
What exactly is the difference in between a Wafer Style Meter and Flanged type Meter?
Each types operate on the principle of Faraday?ˉs Law. Both are durable and accurate in measurements.
But
the lengths of flanged kind meters are specified by ISO standard,
ISO13359 and these of wafer kind are decided by manufacturer.
Wafer type meters will not be getting flanges and are installed by sandwiching the meter in between two flanges of pipe.
There
becoming no flanges for the meter, and length being much less the wafer
meters are economical when compared with flanged meters.
Are Electromagnetic flow meters appropriate for Food and Beverage Sector?
Electromagnetic
flow meters are appropriate for all liquids getting some electrical
conductivity. Food and Beverages Industries can comfortably use
Electromagnetic Flow meters. The meters utilized in food applications
are with complete Stainless Steel Body and having finish connections
appropriate for sanitary applications. Manas offer you these meters in
its SG-Sroat Series.
What's meant by "Empty Tube Detection"? How is the fact that beneficial?
The
primary sensor in the flow meter is supposed to become full together
with the liquid under measurement even when the flow just isn't passing
or when the liquid is below standstill situation. In practice lots of
occasions 1 in the following conditions occurs.
a) When flow stops each of the liquid gets drained and also the main flow sensor either becomes empty or partially filled.
b)
The flowing situations are such that the pipeline remains partially
filled even when Under these circumstances the flow transmitter can not
study the flow price accurately or in some cases even delivers erratic
benefits. For this reason the user gets confused and can't judge what's
going wrong specifically. To assist user below this predicament some
makers (which includes "Manas") add this empty tube detection function.
For this reason function partially filled tube or empty tube is detected
plus the text "Empty Tube" is displayed on transmitter. The user has
now two choices, 1 is always to quit totalization or continue erroneous
totalization with complete awareness.
Can electromagnetic flow meter operate for steam condensate or any other bubbling liquid at high temperature?
The
E.M. Flow meter works around the principle of creating electromotive
force in all elements in the conductor. Right here the conducting
components are liquid elements. Whenever bubbling happens the chain of
conducting elements from 1 electrode to other breaks and the voltage
generated is possessing the discontinuity at various points in the
chain.This prevents the transmitter to study the flow price accurately.
The resolution to produce the transmitter perform below such scenarios
is always to prevent bubbling of liquid when passing by way of the key
flow sensor.
Thus the flow meter can perform for steam condensate at
high temperature in the event the bubbling is usually avoided. There are
numerous strategies to avoid bubbling resulting from high temperature.
What's the difference involving magnetic flow meters and magnetically coupled flow meters?
The
measurement principle of magnetic or electromagnetic flow meters is
depending on Faraday?ˉs Law of Electromagnetic Induction. These meters
include no moving parts.Although as in magnetically coupled meters,
measurement isn't according to Faraday?ˉs law, but is according to
rotation of wheel with velocity of liquid. The rpm value of this
rotating wheel is transferred to the outdoors measurement scheme by
magnetic coupling. Turbine sort and peddle wheel type meters usually use
this scheme. These meters are possessing moving components and s
limitations on accuracy also as durability and capacity to measure
minimum velocity signal. Magnetically coupled meters are some occasions
mistaken as magnetic or electromagnetic flow meters.
Can Electromagnetic flow meter be utilised for measurement of Boiler Feed Water?
篠田麻里子
The
E.M. Flow Meter might be applied for measurement of Boiler Feed water.
Within this application it is advised to install the meter on suction
side from the feed pump.
What would be the a variety of names of Electro Magnetic Flow Meters?
These
meters are known with a variety of names like, Magnetic Flow Meters,
Magmeters, Fullbore electromag, Magnetic Inductive Flow meter and so on.
More:
http://www.rbflowmeter.com/news/14.htm
