Eppendorf Galaxy Gas Analyzer - Manual (Page 33)

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Galaxy® Gas Analyzer — Operating manual
7 Calibration
7 Calibration
7.1 User calibration
The Galaxy Gas Analyzer is fully calibrated at the factory and whenever it is returned for service.
However, to improve accuracy between routine checks, a user/field calibration can be performed.
This section sets out the correct procedures to achieve an accurate user calibration.
Two important terms used in this section are Zero and Span:
• Zero: The point at which the instrument is calibrated when none of the target gas is present.
• Span: The point at which the instrument is calibrated when a known quantity of the target gas
is present.
7.2 Calibration gases
User calibration of the instrument will improve the data accuracy in the range of the calibration
gases used. However, it may cause less accurate readings of concentrations outside this
calibrated range. It is therefore important to select the correct calibration gas for the expected gas
levels for your particular application. Only use gases with a known certified gas concentration.
7.3 Calibration set-up
The regulator supplied with the calibration kit is recommended for your use as its flow and
pressure rates are factory-set. It only requires a few turns to open and no adjustment is
necessary.
(Fig. 24 on p. 34) displays the regulator and tubing equipment set up for user calibration. Contact
your equipment supplier for further information.
Hint!
If calibration is incorrectly performed, it may decrease the accuracy of the instrument.
CAUTION!
Risk of personal injury
 Be sure to read and understand the appropriate material safety data sheet for each gas you
use before proceeding: calibration gases and the use of pressure regulators can be
dangerous.
CAUTION!
Risk of personal injury
 Be sure to read and understand the appropriate material safety data sheet for each gas you
use before proceeding: calibration gases and the use of pressure regulators can be
dangerous.
WARNING!
Risk of personal injury
 When the gas analyzer is being calibrated, there are two possible exits for gas: via the
exhaust port or, should the instrument be over- pressurized, via the 1/16-inch port on the
pressure relief valve (see Fig. 22 on p. 26). We highly recommend therefore that you be sure
to attach exhaust tubing—pre-tested to be leak-free—to both ports. Also ensure that this
tubing’s outlet is in a well-vented area.
 Always perform the calibration in a safe area, taking all necessary precautions as all
pressurized gases are potentially dangerous, and some are flammable.
CAUTION!
 Do not exceed the maximum input pressure of 250 mbar (3.6 PSI).
 Do not exceed the maximum input flow rate of 250 ml per minute.
7
Calibration