Leak Test; Calibrate Measuring Ranges - Siemens OXYMAT 64 Operating Instructions Manual

4.3.2

Leak test

Sample gas must be passed through the sample gas path (including inlet pipe to analyzer,
see adjustment of sample gas flow). A meaningful measurement can only be carried out if
the sensor temperature has already been at its setpoint of 650 °C ± 0.1 K for more than
5 min.
The check is carried out as follows:
● Pass nitrogen at 7.5 l/h into the analyzer (flow over the sensor), and record the displayed
● Then reduce the flow to 6.9 l/h. Record the value again after 5 minutes. With this
● The opposite effect should occur if the sample gas flow is increased by a corresponding
● If the leak test indicates a fault, it must be repeated directly on the analyzer. This will then
See also
Adjusting the sample gas flow (Page 38)
4.3.3

Calibrate measuring ranges

Measuring ranges / spans
The desired spans (start-of-scale and full-scale values of measuring range) can be defined
using function 41. The start-of-scale / full-scale values are allocated to the analog current
values 0/2/4 mA to 20 mA.
If you enter the same values for the start-of-scale and full-scale of a measuring range, this
range is considered as non-existent. Allocate the smallest span (MS) to measuring range 1
and the respectively larger ones to ranges 2 – 4. In general, the following is true for the
allocation: MS1 < MS2 < MS3 < MS4 or MS1 > MS2 > MS3 > MS4.
The start-of-scale value must always be the same in all measuring ranges.
Technical zero
Since a zero point cannot be achieved because of the logarithmic measuring effect, the zero
adjustment is therefore carried out close to the start-of-scale value. This is defined as the
"Technical zero". An appropriate calibration gas must be selected as the "Zero gas" for this
purpose. Its O
Enter the zero setpoint using function 22.
OXYMAT 64
Operating Instructions, 06/2008, A5E00880383-03
O value after 5 minutes.
2
reduction in flow, a leak would result in a larger O
gas path if the O value deviates by more than +2% from the initial value.
2
amount.
indicate whether the leak is in the inlet pipe or in the analyzer itself.
concentration should always be < 30% of the smallest span to be adjusted.
2
4.3 Commissioning and operation
value. There is a leak in the sample
2
Commissioning
39