Endress+Hauser prowirl 77, Руководство по эксплуатации

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Function group: SYSTEM UNITS
Flow unit Unit for the displayed volumetric flow (volume/time).
The flow unit chosen here does apply only for the acyclic requested flow value
in the transducer block. The flow unit for cyclic data exchange must be set in
the AI block.
Selection:
dm
3
/s, dm
3
/min, dm
3
/h, m
3
/s, m
3
/min, m
3
/h,
ACF/s, ACF/min, ACF/h,
ImpG/s, ImpG/min, ImpG/h, USG/s, USG/min, USG/h,
user = user defined unit
(1 dm
3
= 1 liter)
Factory setting: as ordered; if not specified by customer “dm
3
/s” is set.
Volume unit Unit for the totalizer. The unit chosen here applies also for the cyclic data
exchange.
Selection:
dm
3
, m
3
, ACF, ImpGal, Usgal, user = user defined unit
(1 dm
3
= 1 liter)
Factory setting: as ordered; if not specified by customer “dm
3
” is set.
Custom flow
unit
As well as the engineering units offered the flow rate can also be displayed in
other, user-defined units (selection “user” in function “flow unit”, see above).
For this purpose, a conversion factor can be entered in this function giving the
exact ratio of how many of the desired units correspond to the internally used
reference “dm
3
/s”.
1 dm
3
/s = Factor
⋅
[1 user-defined unit]
Example:
1 dm
3
/s is equivalent to
•
60 dm
3
/min
→
factor = 60
•
1/100 hectolitre/s
→
factor = 0.01
•
0.7 kg/s with a fluid density of 700 kg/m
3
→
factor = 0.7
Caution!
Prowirl 77 always measures the volumetric flowrate at actual operating
conditions. The conversion method described here only applies to constant and
exactly known process conditions.
Any deviation from the assumed process conditions can lead to significant
errors.
Note!
•
The factor can be calculated with the E+H sizing program “Applicator”
(version 7.01.00 and higher). Choose Prowirl 77 as instrument and enter the
operating values of your application. The flow rate should be entered in the
desired units. In the window “Conversions” with flow as unit to convert, the
factor is shown above the table at the right (format: X.XXX E (
±
)YY).
On the following pages please find detailed instructions with examples
for the calculation of the factor for mass or corrected volume.
Input:
Value range: 1.0 ·10
-9
...9.999 ·10
9
Note!
Caution!
6 Device Functions Prowirl 77 PROFIBUS-PA
34 Hauser