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Proline Promag L 400
4
Hauser
Symbol
Meaning
-
A0011187
Hazardous area
Indicates a hazardous area.
.
A0011188
Safe area (non-hazardous area)
Indicates a non-hazardous area.
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.
I
L
B
I
U
e
v
A0017035
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
Содержание Promag L 400
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