Dräger Polytron 8720 User Manual

14 Dräger Polytron 8700/8720
Calibration
5 Calibration
Repeat the calibration of the device at regular intervals as
specified in the particular sensor data sheet.
5.1 Calibrating the device
1. Connect the pressure reducer to the calibration gas cylinder.
2. Attach the calibration adapter to the sensor.
3. The gas flow should be between 0.5 and 2.0 l/min.
4. Connect the hose to the calibration adapter.
1 Test gas cylinder
2 Pressure reducer
3Hose
4 Calibration adapter
5.1.1 Zero point calibration
1. Select Calibration > Zero Calibration and confirm.
The Maintenance signal is transmitted.
The message Apply zero gas is displayed.
2. Connect zero gas (synthetic air or nitrogen) to the sensor.
3. Select Next and confirm.
The current value is displayed.
After the displayed value is stable:
4. Select Calibrate and confirm.
The message Please wait… is displayed.
The actual value is displayed.
CAUTION
Danger to health! Do not inhale the test gas. Observe
the hazard information in the corresponding safety
data sheets. Provide venting into a fume cupboard or
outside the building.
Always calibrate the zero point first before the
sensitivity. Otherwise the calibration will be faulty!
NOTICE
Calibration is not possible if the date and time are not
set (see chapter 8.2.3 on page 20).
NOTICE
To perform a zero point or span calibration of the
Polytron 87X0 with a PIR 7000/7200, the PIR 7000/
7200 must be adequately warmed up. Dräger
recommends performing a calibration no sooner
than 3 hours after the device is switched on. For
a calibration, use the splash guard (Order Number:
68 11 911/68 11 912) and the calibration adapter
(Order Number: 68 11 610) (does not apply for duct
mounting or when the process cuvette / process
adapter is used) Observe the installation instructions
for the PIR 7000/7200 accessories.
!
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NOTICE
Ambient air can also be used instead of nitrogen or
synthetic air to zero the sensor, provided it is insured
that the ambient air contains no measured gas or any
other gas for which the sensor may exhibit cross-
sensitivity (see the details in the sensor data sheet).
In this case, neither a gas cylinder nor a calibration
adapter is required for the zero point calibration.
For the Polytron 8720 (with PIR 7200 to detect carbon
dioxide), only nitrogen or synthetic air without any CO
2
content may be used for a zero point calibration.
00433300.eps
2
1
4
3
PIR 7000
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Dräger Polytron 8720 Specifications

General

Brand	Dräger
Model	Polytron 8720
Category	Measuring Instruments
Language	English