Siemens 7MB2041, Руководство по эксплуатации, Страница: 67 / 152

Operation
5.4 Operating functions
OXYMAT 64
Operating Instructions, 06/2008, A5E00880383-03
65
Preparatory steps
● Select the function 23 'Single/total calibration' and activate the parameter 'Total
calibration' there.
● A calibration gas is required for the second step, namely calibration of the sensor signal
span. We recommend a calibration gas with a concentration between 10 and 100 ppm O
2
in N
2
.
Enter the value of this calibration gas in function 22 under 'Setpoint for MR', and activate
the corresponding measuring range. The calibration gas valve of the calibration gas
activated in function 22 is opened.
Procedure
1. Select function 23.
2. Activate the 'Total range calibration' parameter.
3. Select function 22.
4. Enter the O
2
concentration of the calibration gas under 'Setpoint of leading MR'.
5. Select function 26. The following display is output:
ABBRUCH
Setpoint : 20.64 % vol
Act.value: 20.16 % vol
T Sensor : 650.0 °C
Please connect air
...cont. with Span cal.
Start calibration
CANCEL
26 Adjust sensor O
2
Figure 5-23 Calibration of sensor zero
Note
The relay for zero gas 2 is set (if it has been previously appropriately parameterized).
6. Connect ambient air to the sample gas inlet.
You can use air from a compressed air system, or suck in ambient air using a pump.
Provide and input pressure of
– 2000 hPa for high-pressure devices without a built-in pressure regulator and
– 3000 to 6000 hPa for high-pressure devices with a built-in pressure regulator.
– With low-pressure devices you must guarantee that the flow is 7.5 l/h.
Note
Connection to a compressed air system
When connecting to a compressed air system, ensure that the air is free of oil and
grease. Measurements will otherwise be permanently falsified.