The menu » Calibration «
Page 40 of 72 Pages
9023927 - 2nd edition - May 2007
When the displayed value has stabilised:
●
Select » Calibrate « and press the »
« key.
— The message » Zero calibration running « is displayed
— The required value and the actual value are now displayed.
If these are correct as displayed:
●
Select » Back to menu « and press the »
« key.
●
Disconnect the flow of zero gas.
Zero point calibration can be aborted at any time:
●
Use the »
« key to move to » Back « and press the »
« key.
Sub-menu » Span. cal. «
The sub-menu » Span calibration « contains all functions for calibrating the sensitiv-
ity of the installed sensor.
Sensitivity calibration
— The recommended calibration gas concentration for optimum accuracy is be-
tween 40 % and 100 % of the measuring range end value.
1
Remove the inlet line on the Polytron 7500.
2
Fill gas bag (Order No. 68 07 068) with the calibration gas and connect to the in-
let connection of the Polytron 7500.
Calibration procedure (using the DrägerSensor XS NF
3
as an example
)
:
●
Select the menu items » Calibration «, » Span. cal. « and » XS–NF
3
« in this order,
pressing the »
« key after each selection.
— The values for the calibration gas are displayed, for example:
— The calibration gas, concentration and unit can be changed:
●
Select » Cal. gas « and press the »
« key. Select the desired calibration gas
from the list and press the »
« key again.
●
Select » Concentr. « and press the »
« key. Set the calibration gas concentra-
tion (same procedure as for input of a password).
●
Select » Unit « and press the »
« key: Select the desired unit from the list and
Caution:
Test gas must not be inhaled. Risk to health!
Care must be taken about the risks which can arise when using test gas; haz-
ard instructions and safe safety advice must be observed.
For details, see appropriate Safety Sheets.
Cal. gas
: NF
3
Unit
: ppm
Concentr.
: 000025
OK
OK
OK
0422392
7_1
.eps
10 L
2
1
OK
OK
OK
OK
OK
