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Page 4
–22
2104349 rev. AD
Figure 4
–12 Calibration diagram
4.13.4 Differential pressure (DP) calibration checks
As discussed in section 4.13.3, it is recommended that checks of the differential
pressure (DP) be performed prior to and directly following calibration.
A minimum of three differential pressure markers should be set; however, the user
may enter as many DP pressure markers as they prefer. Recording too many
markers may cause the G4 EX to overwrite existing older events. Only the last five
checks are used by the WinCCU editor for calibration adjustment. Enter a low,
mid-low, mid, mid-high and high value.
During normal operation of the G4 EX, the display provides continuous DP
readouts; however, during this procedure, the G4 EX is placed in a temporary
Hold mode.
4.13.4.1
Step-by-step instructions
1)
Enter the Calibration menu’s Check screen. This places the G4 EX on
HOLD. Select the preferred measurement tube from the tree-view.
2) Select DP from the Calibration drop-down menu to the left of the Pressure
Marker table.
3) Click on Enter Pressure Check Value, and select Continuous to update the
current reading.
4) Verify that the vent valve is closed (see Figure 4
–12).
5) Open both the high and low equalizer valves.
6) Close both the downstream and upstream tap valves.
7) Open the atmospheric vent valve.