9023927 - 2nd edition - May 2007
Page 41 of 72 Pages
The menu » Calibration «
press the »
« key again.
If the settings agree with the available calibration gas:
●
Select » Next « and press the »
« key.
— The message » Supply gas: NF
3
with flow rate 500 ml/min « is displayed (this flow
rate is not to be observed for the Polytron 7500).
— Supply calibration gas to the Polytron 7500.
●
Select » Next « and press the »
« key.
— The current value and the expired time are now displayed.
When the displayed value has stabilised:
●
Select » Calibrate « and press the »
« key.
— In the display the maximum value and the current value as well as the remainder
of the sensor vitality are represented as a bar indication.
If these are correct as displayed:
●
Select » Next « and press the »
« key.
●
Disconnect the flow of calibration gas.
— The calibration interval and the date of the next calibration are displayed.
●
Select » Back to menu « and press the »
« key.
Sensitivity calibration can be aborted at any time:
●
Use the »
« key to move to » Back « and press the »
« key.
Autocalibration
Autocalibration consists of fresh-air calibration followed by sensitivity calibration.
This function is intended only for users who are familiar with the unit, since the
sequence of actions may result in calibration errors.
The function can be activated or deactivated with sequence » Settings «, » Sensor «,
» Autocal. «.
Autocalibration procedure (using the DrägerSensor XS NF
3
as an example
)
:
●
Select the menu items "Calibration" and "Autocal." in this order, pressing the
»
« key after each selection.
Attention: There is a danger after the gas is removed that an alarm is given
on the central controller while the gas is returning to normal level!
Attention: The sensor must be supplied with fresh air, otherwise calibration
errors may occur!
OK
OK
OK
OK
OK
OK
OK
OK
