Preparing Calibration Set-Up; Gas Flow For Calibrations; Zero Calibration; Performing Zero Calibration - Dräger PointGard 2000 Series Gebrauchsanweisung

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en Calibration
CAUTION
Triggering alerts by test gas
Applied test gas may trigger alerts.
► Make sure that test gas is no longer applied after
calibration.
Prerequisites:
– Sensor has finished the warm-up phase
(6 Commissioning of the instrument).
– Date and Time are set (11.5 Setting date and time).

8.2.1 Preparing calibration set-up

See the following figure.
Calibration equipment:
– Dräger pressure regulator (1), for reactive gases use
stainless steel pressure regulator
– Dräger calibration adapter (2) (part number 68 10 536).
– Tubing (3)
– Dräger calibration gas cylinder (4)
Prepare calibration
1. Attach the pressure regulator to the calibration gas
cylinder.
2. Fit calibration adapter to the sensor.
3. Connect the tubing to the barbed fitting.
4. Enter the menu, see 7.6.3 Entering the menu
8.3

Gas flow for calibrations

Gas flow varies depending on the sensor.
EC sensor
All other sensors
Gas flow should correspond to the environmental conditions
during operation (e. g. duct measurement with higher flows
than 2 l/min)
18
0.5 l/min ± 10%
0.5 l/min - 2 l/min
8.4

Zero calibration

Ambient air can be used to zero the sensor instead of
Nitrogen or Synthetic Air only if the area is known to be free of
the target gas or any gas to which the sensor may be cross-
sensitive (as listed on the sensor data sheet). In this case, no
cylinder or calibration adapter is needed for the zero
calibration.
WARNING
Calibration fault at zero calibration
Insufficient ambient air flow may cause calibration errors.
► Make sure that the ambient air flow to the sensor is
sufficient.
PointGard 2100 EC-specific:
For Oxygen (O ) sensors a zero calibration does not change
2
any value in the firmware or sensor. Thus, the zero calibration
function can be used to check the correct zero reading when
Nitrogen is applied to the sensor. The PointGard 2100 EC will
indicate a fault state if a zero check fails with a deviation of
more than 0.6 Vol% O from zero. In case of a fault, repeat
2
the zero check or change the sensor if necessary. Use
Nitrogen (N ) for verification.
2
PointGard 2200 CAT-specific:
Sensors must not be calibrated with pure nitrogen. Catalytic
sensors need oxygen to work properly.

8.4.1 Performing zero calibration

Calibration can be aborted at any time. To abort calibration
select back.
Prerequisites:
– Sensor has finished the warm-up phase
– Calibration is prepared.
Perform zero calibration
1. Select Calibration > Zero calibration and confirm.
 The Maintenance signal is transmitted by the analog
interface, no alarm or fault relays are switched and the
symbol is displayed.
 The message Apply zero gas is displayed.
2. Apply synthetic air or nitrogen, if ambient air cannot be
used.
a. Set gas flow corresponding to the sensor used (see
"Gas flow for calibrations", page 18)
3. Select Next and confirm.
 The current value is displayed.
After the test gas has been applied to the sensor for 3
minutes and the displayed value is stable perform
calibration.
4. Select calibrate and confirm.
 The message please wait... is displayed.
 The new current value is displayed.
5. Select Next and confirm.
6. Turn off gas flow and remove the calibration adapter from
the sensor or disconnect tubing.
Instructions for use |
Dräger PointGard 2000 Series