5. MAINTENANCE, ADJUSTMENTS AND CALIBRATION
Page 119 © 1998 DH Instruments, Inc.
5.5.2 CALIB
The calibration functions of this selection are intended for factory use only. Use user
calibration functions to perform calibrations (see Sections 5.3 and 5.4).
Allows editing of PPC2 AF reference pressure transducer, barometer, timebase, and temperature
factory calibrations & settings. All changes are permanent.
5.5.2.1 DUCER
The PPC2 AF allows selection of the current range (unit must be vented) and
editing of the factory adder and multiplier for the current range of the reference
pressure transducer. The factory calibration of the barometer can also be edited.
Adder and multipliers are calculated as:
Meas = (Meas · multiplier) + adder
5.5.2.2 TBASE
The internal timebase reference for the transducer period measurement can be
edited here.
5.5.2.3 TEMP
The ambient pressure temperature measurement calibration and coef can be
edited here. The coef is applied as:
AmbPres = AmbPres + ((Temp - 20) x Coef)
5.5.3 DISP
The PPC2 AF can be set to display low level measured data to aid in troubleshooting. These following
display modes will replace the normal pressure display screen that appears on power up.
You can return to the normal display mode by selecting ‘norm’ in this menu, or by pressing the
ESC key while viewing the display screen. These other display modes are available:
counts: Displays the ambient pressure and ambient temperature counts. These values
can be from 0 to 8 191. These will represent the internal voltage reference and
ground while auto calibrating.
The first count’s value is the ‘X’ joystick
The second is the ‘Y’ joystick.
The third is the ambient pressure.
The fourth is the ambient temperature.
volts: Displays the ambient pressure and temperature voltage measurements. These
represent the internal voltage references while auto calibrating.
periods: The Internal pressure transducers produce frequencies that are pressure and
temperature dependent. This selection displays the high and low pressure and
transducer temperature frequency periods (us).
The first number is the high transducer pressure measurement period.
The second number is high transducer temperature measurement period.
The third number is the low transducer pressure measurement period.
The fourth number is the low transducer temperature measurement period.
To Next Page
Loading...