Airspeed Calibration - PRESTON PRESSURE PS-500 User And Maintenance Manual

1. If not already powered on, apply power to the PS-500 and allow unit to warm up for a
minimum of 10 minutes.
2. Gently close the Pressure Control valve, Pressure Vent valve, and Crossbleed valve.
3. Connect a pressure standard to the Pressure Port. Maintain the altimeter side at 0 feet.
4. Press the Units button to set the airspeed measurement units to read in mbar.
5. Press the Exit and Leak Check buttons. The display will change to:
Enter Cal Mode?
6. Press the Leak Check button to proceed with calibration or select the Exit button to
exit out of the calibration mode without any changes being made.
7. At this point the display will read:
Go to 50 Knots
Next at 0 Feet
Using an attached pressure standard, go to an airspeed 50.0 knots (while always
maintaining the static pressure of 0 feet), as read from the pressure standard.
8. X.X Knots
Enter YY 
Where X.X is the sensed knots and YY is the internal correction factor currently stored in
the calibration memory.
9. When the pressure is stable for approximately 30 seconds, note the pressure displayed
on the PS-500 airspeed display in calibration mode.
If the displayed speed is lower or higher than the standard, press the Exit or Leak Check
button as needed to incrementally raise or lower the pressure to be equivalent to the
standard.
As the pressure is adjusted, note that the displayed correction factor also changes. Use
this to fine-tune the pressure as close as you can to the standard.
If satisfied with the results, press the Units button to save the calibration and exit back to
the mBar mode.
Airspeed Calibration Procedures
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