Adjusting the sensitivity for an individual
measuring channel
A potentially activated H
offsetting is automatically temporarily deactivated
2
during a manual adjustment, a PC calibration or an automatic Bump Test for
the relevant duration.
–
The span adjustment can be carried out specifically for individual sensors.
–
During the span adjustment, the sensitivity of the selected sensor is set to
the value of the used test gas.
–
Use a standard test gas.
–
Allowed test gas concentration:
DUAL IR Ex
20 to 100 %LEL
IR Ex
DUAL IR CO
2
0.05 to 5 vol.-%
IR CO
2
O
10 to 25 vol.-%
2
CO
20 to 999 ppm
H
S
5 to 99 ppm
2
H
HC
0.5 to 4.0 vol.-%
2
Test gas concentration of other gases: see Instructions for Use for the
respective DrägerSensors.
1)
Depending on the selected data set.
2)
Depending on the measuring range and the measuring accuracy.
Connect the test gas cylinder with the calibration cradle.
Vent the test gas into a fume cupboard or into the open air (with a hose
connected to the second connector of the calibration cradle).
Risk to health! Do not inhale the test gas.
Observe the hazard warnings of the relevant safety data sheets.
Switch on the instrument and insert it into the calibration cradle.
Press the [ + ] key and keep it pressed for 5 seconds to call the calibration
menu, enter the password (password on delivery = 001).
Use the [ + ] key to select the single gas adjustment function. The symbol for
span adjustment »
« flashes.
Press the [ OK ] key to start the channel selection.
NOTICE
1) 2)
1) 2)
/ 5 to 100 vol.-%
2)
WARNING
In the case of the CO
channel there is a 2-stage calibration routine:
2
The zero point adjustment takes place first and is then followed by the span
adjustment.
The display flashes the gas of the first measuring channel, e.g.
–
» ch
- LEL «.
4
Press the [ OK ] key to start the adjustment function of this measuring
channel, or use the [ + ]- key to select another measuring channel (O
%, H
S - ppm or CO - ppm, etc.).
2
–
The test gas concentration is displayed.
Press the [ OK ] key to confirm the test gas concentration or use the [ + ] key
to change the test gas concentration and complete the process by pressing
the [ OK ] key.
–
The measurement value flashes.
Open the test gas cylinder valve to let gas flow over the sensor with a
volume flow of 0.5 l/min.
–
The displayed, flashing measurement value changes to the value according
to the supplied test gas.
When the measurement value displayed is stable (after at least
120 seconds):
Press the [ OK ] key to perform the adjustment.
–
The display containing the current gas concentration changes with the
display » OK «.
Press the [ OK ] key or wait about 5 seconds in order to complete the
adjustment of this measuring channel.
–
The next measuring channel may appear for adjustment.
–
After the adjustment of the last measuring channel, the instrument changes
to the measuring mode.
Close the test gas cylinder valve and remove the instrument from the
calibration cradle.
If a fault has occurred during the span adjustment:
–
The fault message »
« appears and »
respective sensor instead of the measured value.
In this case, repeat the adjustment.
If necessary, replace the sensor.
NOTICE
« is displayed for the
- vol.-
2
23