Sub-Menu » Span. Cal - Dräger Polytron 7500 Instructions For Use Manual

The menu » Calibration «
When the displayed value has stabilised:
Select » Calibrate « and press the »
— 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 »
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 »
Sub-menu » Span. cal. «
The sub-menu » Span calibration « contains all functions for calibrating the sensitiv-
ity of the installed sensor.
Sensitivity calibration
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.
— 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
Select the menu items » Calibration «, » Span. cal. « and » XS–NF
pressing the » « key after each selection.
OK
— The values for the calibration gas are displayed, for example:
Cal. gas : NF
3
Unit : ppm
Concentr. : 000025
— The calibration gas, concentration and unit can be changed:
Select » Cal. gas « and press the »
from the list and press the »
Select » Concentr. « and press the »
tion (same procedure as for input of a password).
Select » Unit « and press the »
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« key.
OK
« key.
OK
OK
as an example):
3
« key. Select the desired calibration gas
OK
« key again.
OK
« key. Set the calibration gas concentra-
OK
« key: Select the desired unit from the list and
OK
« key.
« in this order,
3
1
2
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9023927 - 2nd edition - May 2007