ACOEM Met One Instruments GAS-1060, User Manual

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Calibration Page 91
5. Back - Pressure Calibration Menu - (read note) - OK.
5.3 Pressure Calibration (Internal Pump Option Only)
The internal pump requires a separate pressure calibration procedure that replaces the one used in
Section 5.2.
Note: Ensure that the instrument has been running for at least one hour before any calibration is
performed to ensure sufficient stability.
Note: Ensure units of measure are the same on both the barometer and instrument.
Equipment Required

Barometer
Procedure
1. Disconnect any external tubing connected to the rear ports of the instrument.
2. Open - Main Menu

Calibration Menu

Pressure Calibration - (read displayed note) - OK.
Note: This action will place the valve sequence on hold; normal sampling will be interrupted.
3. Edit - Vacuum Set Pt. - (Read displayed instructions) - OK.
4. Connect a barometer to the Sample Port (refer to Figure 5).
5. Wait 2-5 minutes and ensure the pressure reading on the barometer has dropped and is stable.
6. Enter the barometer reading into the instrument - Accept.
7. Read displayed instructions - OK.
8. The pump should now stop automatically. Disconnect the barometer from the Sample Port .
9. Wait 2-5 minutes and enter the ambient barometer reading into the instrument - Accept.
Note: Both of the pressure sensors should now be displaying the current ambient pressure and they
should be the same value within 3 torr of each other.
10. Back - Pressure Calibration Menu - (read note) - OK.
5.4 Zero Calibration
Zero precision checks and calibrations are used to determine the zero response of the instrument
and set the offset of the instrument if required.