Endress+Hauser Proline Promag 55 PROFIBUS PA, Руководство по эксплуатации

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Proline Promag 55 PROFIBUS PA Commissioning
Hauser 75
Calculation formula (example)
The mass flow of the target fluid is calculated, for example, as follows:
Configuration of the "Solids content flow" function
Please note the following points when commissioning the solids content flow function:
1. Make sure that the settings in the following functions for the flowmeter and the external
density meter are identical:
– UNIT DENSITY (0420)
2. Then enter the following density values:
SPECIAL FUNCTIONS > SOLID CONTENT FLOW > CONFIGURATION >
CARRIER DENSITY (7711) and TARGET MAT. DENSITY (7712)
3. Enter the desired density unit:
MEASURED VARIABLES > SYSTEM UNITS > ADDITIONAL CONFIGURATION > UNIT
DENSITY (0420)
4. If necessary, assign the appropriate solids flow measured variables to a display line or an analog
input functionblock. For process control you can also assign user-definable limit values to the
solids flow (
→
see the following examples).
Case study 1:
You wish to configure the totalizer for totalizing the complete solid mass flow (e.g. in tons).
1. Open the ASSIGN function of the totalizer (> TOTALIZER > CONFIGURATION > ASSIGN).
2. Assign the TARGET MASS FLOW variable to the totalizer.
Case study 2:
You would like to issue a warning message via the relay if the solids flow exceeds 60% of the total
mass flow (transport solids).
1. Open the ASSIGN function of the relay output (> OUTPUTS > RELAY OUTPUT >
CONFIGURATION > ASSIGN)
2. To do so, assign the LIMIT TARGET MASS FLOW % variable to the relay output.
3. Then, you can use the ON- or OFF-VALUE function to enter the desired percentage value (%)
for the maximum permitted solids flow (e.g. switch on if solid content is 65%; switch off if solid
content is 55%).
m
Z
= V
⋅ (ρ
M
− ρ
C
) / (
1
− ρ
C
/ρ
S
)
m
Z
V
ρ
C
ρ
S
ρ
M
=
=
=
=
= Mass flow target fluid (solids), e.g. in kg/h
Volume flow (total fluid), e.g. in m
3
/h
Density of carrier fluid (transport liquid: e.g. water)
Density of target fluid (solids transported: e.g. stone, sand, lime powder, etc.)
Total fluid density