ABB XSeriesG4 User Manual page 128

During normal operation the display provides continuous DP readouts. However during this procedure the flow computer is
placed in a temporary hold mode.
IMPORTANT NOTE: During this procedure, the user will pressure the high side of the cell by closing both the
high and low side orifice valves, open the vent to atmosphere and the low side bypass valve, and closing the
high side bypass valve.
Equipment needed:
-Calibration standard
To perform the Differential Pressure (DP) calibration checks:
Connect the PC running PCCU32 to the flow computer with either an MMI cable (RS-232), a USB cable or an
Ethernet cable
Open PCCU.
Select the Calibration button from the toolbar. The Flow Computer is placed in hold.
Select the desired measurement tube from the tree view in the left pane.
Select DP from the calibration drop down box to the left of the pressure marker table.
Click on the Enter Pressure Check Value and select Continuous to update the Current Reading.
Verify that the vent valve is closed (Figure 92:).
Open both the high and low equalizer valves.
Close both the downstream and upstream tap valves.
Open the atmospheric vent valve.
Enter a pressure marker for differential pressure 0.0.
Click OK.
Close the high side equalizer valve
Connect the Calibration Standard to calibration test port.
Pressure to the next desired verification pressure.
Enter the pressure value from the calibration source once the current reading stablizes.
Click OK.
Repeat steps 11 through 13 for each pressure check value.
Determine if calibration is required when all Differential Pressure markers have been set.
Return the manifold to service, if no calibration is required, before exiting calibration mode.
The differential pressure has been calibrated.
IMPORTANT NOTE: For additional information regarding Differential Pressure Calibration Checks, see PCCU
Help Files.
6.13.5 Calibrating Static Pressure
A three or five point pressure method may be used to calibrate the static pressure cell. These different pressures are applied to
the cell from a known traceable source with resultant pressure values entered using PCCU software.
When doing the following procedures wait for the display to stabilize. If the flow computer is not in the calibration mode the
display will not necessarily match applied cell pressures.
129 XFC G4 2103335 Rev AB