Endress+Hauser Proline Promag W 500 - Function and System Design; Measuring Principle

Proline Promag W 500
Endress+Hauser 5
Symbols in graphics
Symbol Meaning
1, 2, 3, ... Item numbers
1.
,
2.
,
3.
, … Series of steps
A, B, C, ... Views
A-A, B-B, C-C, ... Sections
-
Hazardous area
.
Safe area (non-hazardous area)
Flow direction
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