Theory Of Operation - Siemens SITRANS F M MAG 3100 Operating Instructions Manual

3.3

Theory of operation

The flow measuring principle is based on Faraday's law of electromagnetic induction.
U = When an electrical conductor of length L is moved at velocity v, perpendicular to the
i
lines of flux through a magnetic field of strength B, the voltage Ui is induced at the ends of
the conductor
U = L x B x v
i
● Ui = Induced voltage
● L = Conductor length = Inner pipe diameter = k
● B = Magnetic field strength = k
● v = Velocity of conductor (media)
● k = k
Ui = k x v, the electrode signal is directly proportional to the fluid velocity
Sensorprom memory unit
All SITRANS F M electromagnetic flowmeters feature a unique SENSORPROM® memory
unit which stores sensor calibration data and transmitter settings for the lifetime of the
product.
At commissioning the flowmeter commences measurement without any initial programming.
The factory settings matching the sensor are stored in the SENSORPROM® unit. Also
customer- specified settings are downloaded to the SENSORPROM® unit. Should the
transmitter be replaced, the new transmitter will upload all previous settings and resume
measurement without any need for re-programming.
Furthermore, the "fingerprint" used in connection with the Siemens Flow Instruments
Verificator is stored during the sensor calibration.
USM II "Plug & Play" add-on communication modules
USM II - the Universal Signal Module with "Plug & Play" simplicity makes it easy to access
and integrate the flow measurement with almost any system. It ensures the flowmeter will be
easy to upgrade to new communication platforms in the future, too.
SITRANS F M MAG 3100
Operating Instructions, 06/2010, A5E03005599-01
x k
1 2
1
2
Description
3.3 Theory of operation
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