Endress+Hauser prowirl 77, Руководство по эксплуатации

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9 Technical Data
Application ranges
Designation Flow measuring system “Prowirl 77”
Function Measurement of volumetric flowrate of saturated steam, superheated
steam, gases and liquids.
Operation and system design
Measurement principle The Prowirl 77 vortex flowmeter operates on the physical principle of
Karman vortex shedding.
Measurement system The “Prowirl 77” instrument family consists of:
•
Transmitter: Prowirl 77 “PFM”
Prowirl 77 “4...20 mA/HART”
Prowirl 77 “PROFIBUS-PA”
•
Meter body: Prowirl 77 W
wafer version, DN 15...150
Prowirl 77 F
flanged version, DN 15...300,
bigger nominal diameters on request
Prowirl 77 H
high pressure version, DN 15...150
Input variables
Measured variables The average flow velocity and volumetric flow rate are proportional to the
frequency of vortex shedding behind the bluff body.
Measuring range The measuring range is dependent on the fluid and the pipe diameter
(see page 60).
•
Full scale value: – Liquids: v
max
= 9 m/s
– Gas / steam: v
max
= 75 m/s
(DN 15 v
max
= 46 m/s)
•
Lower range value: – depends on the fluid density and the
Reynolds number, Re
min
= 4000,
Re
linear
= 20000
DN 15 / 25: m/s with
ρ
in
DN 40...300: m/s with
ρ
in
Output variables
Output signal PROFIBUS-PA interface:
according to EN 50170 Volume 2, PROFIBUS
Transmission technique IEC 1158-2
PROFIBUS profile Class B V2.0
PA-Function Slave
Current consumption 12 mA
Permissible power voltage 9 V...32 V (intrinsically safe version: 9 V...24 V)
FDE (Fault Disconnection
Electronic) 0 mA
v
min
=
6
ρ
kg
m
3
v
min
=
7
ρ
kg
m
3
Prowirl 77 PROFIBUS-PA 9 Technical Data
Hauser 55