Calomat 7 - Siemens SIPROCESS GA700 Operating Instructions Manual

Commissioning
9.5 Zero point error
Information on interference gas correction is available in the following operating manuals:
● Operating with the Local User Interface Table A-2 References 1 - Operating Manuals LUI
(Page 159)
● Operation with SIMATIC PDM Table A-3 References 2 - Operating Manuals PDM
(Page 159)
9.5.2

CALOMAT 7

Overview
To determine the cross-interferences of accompanying gases with several interference gas
components, you must know the sample gas composition. The following table contains the
zero offsets for the carrier gas N
Table 9- 6
If you are using accompanying gas concentrations ≠ 10%, you can use the corresponding
multiples of the respective table value as a good approximation. This procedure applies
depending on the type of gas for an accompanying gas concentration range up to approx.
25%.
The thermal conductivity of most gas mixtures has a non-linear response. Even ambiguous
results can occur in specific concentration ranges, e.g. with H
In addition to the zero offset, the accompanying gas also affect the characteristic curve. For
most gases, however, the effect on the characteristic curve is negligible.
114
as H
2
Zero offset in the system H
Interference gas
CH
4
C H
2 6
C H
3 8
CO
CO
2
O
2
N O
2
NH
3
Ar
He
SF
6
SO
2
Synthetic air
H O (3%)
2
equivalent values with 10% interference gas
2
in N
2 2
H equivalent values with 10% inference gas
2
Operating Instructions, 05/2018, A5E31930403-06
1.77%
0.47%
-0.28%
-0.10%
-0.84%
0.19%
-0.83%
1.45%
-1.22%
6.32%
-2.15%
-1.47%
0.40%
0.38%
in He mixtures.
2
Wall-mounted device