4.7 Oxygen Analyser Calibration
The O
analyser should be calibrated at least once every three months against
2
a calibrated gas supply or a calibrated independent analyser.
Note. If using calibration gas, ensure that purity is as close to the production
gas purity as possible (minimum of 50ppm). Do not exceed 7barg pressure.
For low purity applications the calibration may be performed using compressed
air. This method is not recommended when the purity of the gas is critical.
Select menu 3.1 and enable the O
Over-ride.
Calibrated Gas Supply
Connect the gas supply to the O
generator.
Locate the calibration ball valve (2) inside of the shroud and rotate the handle
clockwise so that it is pointing upwards as shown. Wait approximately fifteen
minutes for the O
reading to stabilise. Once stable enter the calibrated level
2
as specified below.
Calibrated Independent Analyser
Connect the analyser to the nitrogen outlet port of the generator. Wait
approximately fifteen minutes for the O
the calibrated level as specified below.
Compressed Air
Connect the O
sample line between the elbow push in fitting, located on the
2
ball valve (3), and the O
Analyser calibration port (1).
2
If a sample line other than the one provided by domnick hunter
is used ensure that it is suitable rated for the working pressure
of the generator.
Open the ball valve (3) and rotate the handle of the calibration ball valve (2) so that it is pointing upwards as shown. Wait approximately fifteen
minutes for the O
reading to stabilise. Once stable enter the calibrated level as specified below.
2
The sample line will need to be depressurised prior to disconnection. Close the ball valve (3) and wait until the pressure
shown on the pressure gauge (4) reaches zero. When the line is fully depressurised, rotate the handle of the calibration
ball valve (2) so that it is pointing downwards and disconnect the line from the generator.
4.7.1 Entering the calibrated level
Select menu 3.2. The current reading from the 0
Using the
and
keys enter one of the following as appropriate:
•
the purity of the calibration gas,
•
the purity reading from the independent analyser,
•
Oxygen content of the compressed air (20.9%).
Press
to send the calibration level to the O
On successful completion of the calibration the new O
display. If the calibration is not successful the original reading from the analyser will be loaded. Should this
occur repeat the above steps.
On completion of the calibration, return the calibration ball valve back to its original position and remove
the regulated calibration gas supply or independent analyser as applicable.
Disable the O
Alarm Over-ride.
2
When returning to the main operating menu, "CAL" will be shown on the top line of the display. This will
remain for a period of twenty minutes after the calibration. Throughout this time period the O2 alarm is
overridden, to allow the sensor to return to the required level.
Alarm
2
3.1
O2 Alarm
Over-ride
Analyser calibration port (1) on the side of the
2
reading to stabilise. Once stable enter
2
analyser will be displayed on the controller.
2
analyser.
2
reading will be shown on the bottom line of the
2
= 1
17
EN
Operating the Generator
4
3.2
O2 Calibration
=
4.95%
3.2
O2 Calibration
=
5.00%
3.2
O2 Calibration
Please Wait...
3.2
O2 Calibration
=
5.00%
3.1
O2 Alarm
Over-ride
= 1
O2 = 5.00 %
CAL
Running