Installation
EngyCal
®
RH33
20
Hauser
4.6
Requirements for sizing
To avoid systematic errors, the temperature sensors must be installed shortly upstream and
shortly downstream from the heat exchanger. If the pressure difference between the
temperature measuring points is too large, this can result in an excessively large systematic
error, see the table below.
Temperature differential in [K]
Diff in [bar]
3
5
10
20
30
40
50
60
0.5
0.2
0.2
0.1
0.1
0.1
0
0
0
1
0.5
0.4
0.3
0.2
0.1
0.1
0.1
0.1
2
0.9
0.7
0.5
0.3
0.2
0.2
0.1
0.1
3
1.4
1.1
0.8
0.5
0.3
0.2
0.2
0.2
4
1.8
1.5
1.0
0.6
0.4
0.3
0.3
0.2
5
2.3
1.9
1.3
0.8
0.5
0.4
0.3
0.3
6
2.7
2.2
1.5
0.9
0.6
0.5
0.4
0.3
7
3.2
2.6
1.9
1.1
0.7
0.6
0.5
0.4
8
3.6
3.0
2.0
1.2
0.9
0.7
0.5
0.4
9
4.1
3.3
2.3
1.4
1.0
0.7
0.6
0.5
10
4.5
4.0
2.5
1.5
1.1
0.8
0.7
0.5
The values are indicated as factors of the maximum permitted error of the BTU meter (with
Δ
Q
min
= 3 K (5.4 °F)). The values below the gray line are higher than 1/3 of the maximum
permitted error of the BTU meter (with Δ
Q
min
= 3 K (5.4 °F)).
If 2 different heat carriers (e.g. room heating and household hot water) merge shortly
upstream from the temperature sensor, the optimum position of this sensor is directly
downstream from the flow measuring point.
4.7
Post-installation check
For installing the BTU meter and the associated temperature sensors, observe the general
installation instructions according to EN 1434 Part 6 and Technical Guideline TR-K 9 of the
PTB (the German National Metrology Institute). TR-K 9 is provided on the CD-ROM supplied
or can be downloaded from the PTB website.
Содержание EngyCal RH33
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