Ultramat 7 - Siemens SIPROCESS GA700 Operating Instructions Manual

Overview
Table 9- 1
Measuring range
0 to vol. % O
to 100 Vol. % O
pressed zero point with
full-scale value 100 Vol. %
O )
2
0 ≤ 21 ≤ 100% O
pressed zero with
21 Vol. % O
span)
Reference gas "Air"
Air only has a constant O
For measurements with measuring ranges of 2 %, the exact O
"Air" must be known. Use this value as the setpoint for a zero point calibration.
Selection of the reference gas
The various measuring spans must have at least one common value. This value is then
defined as the "physical zero point" and applies to all the measuring ranges. The reference
gas can be selected on the basis of the "physical zero point".
The following example with four measuring ranges illustrates this:
Table 9- 2
Measuring range
17 to 22% O
15 to 25% O
0 to 25% O
0 to 100 % O
Exception: If the smallest measuring span is ≥ 5% O
amounts to no more than 16 % O
range. The purity of the reference gas has to be appropriate for the measuring task.
9.4.1.2

ULTRAMAT 7

In an analyzer module without physically suppressed zero point, meaning with characteristic
initial value of zero, use nitrogen as the reference gas (purity 4.6).
Wall-mounted device
Operating Instructions, 05/2018, A5E31930403-06
9.4 OXYMAT 7 / ULTRAMAT 7: Introduction of reference gas
Overview of the reference gases
Recommended
reference gas
N
2 2
(sup- O
2 2
(sup- Air
2
within the
2
share if the humidity is constant. Therefore use dry air.
2
Selection of the reference gas
Criterion for selection of the reference gas
The span of 17 to 22% O
2
point may lie within this range. Air (20.95 % O
2
ence gas.
2
2
2
Reference gas connection
pressure range
2 000 to 4 000 hPa above
sample gas pressure
(max. 5 000 hPa absolute)
100 - 150 hPa with respect
to sample gas pressure
is part of all measuring ranges. The physical zero
2
and the distance to the reference gas
2
, the physical zero point can also lie outside the measuring
Commissioning
Comment
The reference gas flow
is set automatically to
between
5 and 12 ml/min.
The sample gas pres-
sure may fluctuate by a
max. 50 hPa around
the ambient pressure
share of the reference gas
2
%) is suitable as the refer-
2
109