Endress+Hauser Proline Prosonic Flow P 500, Руководство пользователя

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Proline Prosonic Flow P 500
4 Hauser
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 The measuring system uses a measurement method based on the transit time difference. In this
measurement method, acoustic signals (ultrasonic) are transmitted between two sensors. Signal
transmission is bidirectional, i.e. the sensor operates as both a sound transmitter and a sound
receiver.
As the speed of propagation of the sound waves is slower against the flow direction than in the flow
direction, this results in a transit time difference. This transit time difference is directly proportional
to the flow velocity.
The measuring system calculates the volume flow of the medium from the measured transit time
difference and the pipe cross-sectional area. The sound velocity of the medium is simultaneously
measured along with the transit time difference. With this additional measured variable, it is
possible to differentiate between different media or monitor the medium quality.
t
a
t
b
a
b
Q
1
A0041971
1 Transmitter
a Sensor
b Sensor
Q Volume flow
∆t Transit time difference ∆t = t
a
- t
b
; flow velocity v  ∆t