Dräger PIR 3000 Instructions For Use Manual page 12

Operational Characteristics
Commercially available calibration gas can be used to calibrate the respective gas
category (methane, propane, ethylene). The highest accuracy is achieved using test
gas concentrations of 40 to 70 percent of the measurement span.
The infrared gas transmitter Dräger PIR 3000 can also be used to measure other
gases than mentioned above. For detailed information, refer to "Substitute Gas Cali-
bration" on page 16.
●
Select the measured gas in the corresponding table and determine the corre-
sponding gas category.
●
Set the gas transmitter to the determined gas category.
Where possible, calibration gas should match with the measured gas for span cali-
bration. In exceptional cases, span calibration can be carried out using a suitable
substitute gas and the associated calibration factor. The suitable substitute gas as
well as the associated calibration factor is shown in the table "Substitute Gas Cali-
bration" on page 16.
●
Select the substitute gas (gas category) and the calibration factor in table "Substi-
tute Gas Calibration" on page 16.
●
Multiply the concentration of the substitute gas by the calibration factor to get the
gas concentration to be set.
Example:
Measured gas:
Gas category:
Calibration factor:
Span gas concentration:
Setting:
CAUTION:
Never inhale test gas. Danger to health!
Observe the safety information in the corresponding safety data sheets.
Ensure that gases are vented or otherwise guided outside the building.
12
n-octane
Propane (see table "Substitute Gas Calibration",
page 16)
1.8 (in table "Substitute Gas Calibration", page 16)
40 %LEL propane (bottle concentration)
40 %LEL x 1.8 (calibration factor) = 72 %LEL