Zero Calibration - MSA Altair 5X Mode D'emploi

• A special pressure regulator
• The shortest possible connection tubes between the
pressure regulator and the instrument.
• Connection tubes made from a material that does not absorb
the test gases (e.g., PTFE).
NOTE: If using normal tubes and pressure regulators, expose them
to the required test gas for an extended time period. Keep
these materials dedicated for use with that test gas only;
do not use them for other gases.
For example: for chlorine, allow the entire contents of a test
gas cylinder to flow through the pressure regulator and
tubes before using to calibrate the instrument. Mark these
materials for use with chlorine only.

3.8.1 Zero Calibration

1. Press the ▲ button for five seconds in the NORMAL
MEASUREMENT page.
• ZERO screen displays:
To skip the ZERO procedure and move directly to the span
calibration procedure, push the ▲ button. If no button is pushed for
30 seconds, the instrument prompts the user to perform a SPAN
calibration before the instrument returns to the NORMAL
MEASUREMENT page.
To perform ONLY a Fresh Air Setup at this time, press the
button. The instrument then performs a Fresh Air Setup as
described in Section 3.2.2. When the Fresh Air Setup is complete,
the instrument returns to the normal Measure screen.
2. Press the ▲ button to confirm the ZERO screen, i.e., to execute
zero calibration.
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