Checking The Response Time (T90); Calibrate The Gas Detector - Dräger X-am 3500 Gebrauchsanweisung

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en Maintenance
Alternatively the pump adapter can be used with an on-
demand valve.
2. Connect the hose to the test gas cylinder and the inlet on
the calibration adapter.
3. If needed, connect a second hose (max. length: 2 m) to
the outlet on the calibration adapter to direct the test gas
to an exhaust or outside. Make sure that these is sufficient
ventilation in room or vehicles.
4. Open the bump test (depending on the configuration).
a. Select > Maintenance > Bump test (if configured
using the Dräger CC-Vision PC software).
b. > Login
Enter and confirm the password.
Select Maintenance > Bump test.
5. Open the valve on the test gas cylinder, the volume flow
must be 0.5 /min and the gas concentration must be
higher (lower with oxygen) than the alarm threshold
concentration that is to be tested.
6. Select to start the bump test.
 All measuring channels which are included in the
bump test flash, and all others are greyed out. When a
measuring channel successfully passes the test,
appears.
7. The bump test is complete when all measuring channels
included in the test successfully passed or failed the test.
8. Close the valves on the test gas cylinder.
● Select and then confirm the dialog to discard the
result.
● Select to confirm the result.
9. Remove the calibration adapter.
If there was an error during the bump test:
1. An error is displayed for the measuring channel.
2. Repeat the bump test.
3. If necessary, replace the sensor.
36

5.4.2 Checking the response time (t90)

1. Carry out a bump test and perform a simple check of the
response time.
a. Connect the test gas to the calibration adapter and
!
open the valves on the test gas cylinder so that the
calibration adapter is flushed with test gas.
b. Fit the calibration adapter on the gas detector and note
the starting point.
c. Determine the time until 90 % of the test gas
concentration is reached.
2. Compare the measured response time with the previous
bump tests and the t90 values that are indicated in the
enclosed supplementary documentation (part no.
9033655).
The determined T90 adjustment time may differ from the
certified adjustment time as this simplified method does not
comply with the standard.
5.5

Calibrate the gas detector

WARNING
Incorrect measured values!
An incorrect calibration may prevent alarms from triggering, or
alarms may trigger late.
► Do not close the outlet of the calibration adapter / exhaust
gas hose.
► Always carry out the fresh air / zero calibration before the
span calibration.
NOTICE
Damage to the sensors!
When using the exhaust gas hose, the sensors may be
damaged in the case of direct suction on the exhaust gas
hose.
► If necessary, lead the exhaust gas hose (max. length 2 m)
to an exhaust of outside.
If measurement gas or calibration gas is changed, the
affected channel must be calibrated.
Observe the following notices for the calibration:
● For the fresh air calibration of Dräger IR sensors for
explosive hydrocarbon, it is assumed that the change in
the zero-point leads to a change of less than or equal to
±5 %LEL of the measured value at 50 %LEL. If the
deviation is greater than ±5 %LEL, the span calibration is
invalid.
● For the zero-point calibration of Dräger IR sensors, it is
assumed that the change in the zero-point leads to a
change of less than or equal to ±5 %LEL or 0.05 Vol%
CO of the measured value at 50 %LEL or 0.5 Vol% CO
2
If the deviation is greater than ±5 %LEL or 0.05 Vol% CO
the span calibration is invalid and an error or a warning is
displayed (configurable).
● For a span calibration of Dräger IR sensors, it is assumed
that a valid zero-point calibration exists (no more than
30 min. old), otherwise an acknowledgeable warning is
displayed.
Instructions for use |
X-am
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2
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2
®
3500