Endress+Hauser magphant, Руководство по эксплуатации

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Technical data Magphant
34 Hauser
15 Technical data
15.1 Application
The measuring device is intended only for the flow measurement of liquids with a
minimum conductivity of 20 µS/cm.
To ensure that the device remains in proper operating condition for its service life, use the
measuring device only for media against which the process-wetted materials are
sufficiently resistant.
15.2 Function and system design
Measuring principle Following Faraday's law of magnetic induction , a voltage is induced in a conductor moving
through a magnetic field.
U
e
L
B
I
I
v
A0028962
Ue Induced voltage
B
Magnetic induction (magnetic field)
L Electrode spacing
I Current
v Flow velocity
In the electromagnetic measuring principle, the flowing medium is the moving conductor.
The voltage induced (U
e
) is proportional to the flow velocity (v) and is supplied to the
amplifier by means of two measuring electrodes. The flow volume (Q) is calculated via the
pipe cross-section (A). The DC magnetic field is created through a switched direct current
of alternating polarity.
Formulae for calculation
• Induced voltage U
e
= B · L · v
• Volume flow Q = A · v
Measuring system The device consists of a transmitter and a sensor.
The device is available as a compact version:
The transmitter and sensor form a mechanical unit.