PPC3™ OPERATION AND MAINTENANCE MANUAL
© 2002-2007 DH Instruments, a Fluke Company Page 130
5.2.8 Q-RPT CALIBRATION/ADJUSTMENT WITHOUT CALTOOL
FOR RPTS SOFTWARE
PRINCIPLE
The PPC3 Q-RPTs can be calibrated and adjustments made without using CalTool for RPTs
software. This requires:
• Applying pressures with a calibration standard and recording the pressures measured
by PPC3.
• Calculating new PA and PM values and entering them.
• Setting P
offset
to zero for Axxx Q-RPTs.
Before proceeding to calibrate a reference pressure transducer without using CalTool for
RPTs software, Sections 5.2, Calibration of Reference Pressure Transducers, 5.2.1
PRINCIPLE, 5.2.2 Equipment Required, 5.2.3 Setup and Preparation should be reviewed
thoroughly.
OPERATION
The typical procedure for calibrating a Q-RPT is:
Set-up and prepare the PPC3 for calibration (see Sections 5.2.2, 5.2.3).
Use the [RPT] function key to select the Q-RPT to be calibrated (see Section 3.3.5).
Be sure to set the DF range (not an AutoRanged range).
Use [HEAD] to set the HEAD to zero (see Section 3.3.7). Use [UNIT] to set the desired
pressure unit of measure (see Section 3.3.2). Use [MODE] to set the desired pressure
measurement mode (see Section 3.3.3). Axxx (absolute) Q-RPTs that will be used in
gauge measurement mode only, may be calibrated in gauge measurement mode with a
gauge pressure standard (see Section 5.2.5).
Use [SPECIAL], <1AutoZ> to access the AutoZ function (see Section 3.5.1).
If calibrating in absolute measurement mode, turn AutoZ ON if it is left ON in normal
PPC3 operation. If calibrating in gauge measurement mode, always turn AutoZ ON.
Use [SPECIAL], <8cal>, <1Hi RPT> or <2Lo RPT>, <1view>, read and record the current
values of PA and PM for the Q-RPT to be calibrated. If calibrating in absolute mode, also
record the value of P
offset
.
Run the recommended calibration point sequence for the Q-RPT (see Section 5.2.4)
recording the pressure applied by the standard and the PPC3 reading at each calibration
point. Dwell at least 90 seconds at each point after setting the reference pressure to allow
full stabilization before taking data. The data recorded is the “as received” data for this
calibration.
Enter the calibration pressures and PPC3 readings into a spreadsheet. Calculate the
“non-corrected” PPC3 readings by backing out the PA, PM and P
offset
(P
offset
only in the case
of Axxx (absolute) Q-RPTs in absolute mode) recorded in Step
above, following:
non-corrected reading = ((corrected reading - PA)/PM ) + P
offset
Perform a linear regression to find the offset and slope that best fit the non-corrected
PPC3 readings to the calibration standard pressures. The offset is the new value of PA,
the slope is the new value of PM.
Press [SPECIAL], <8Cal>, <1Q-RPT>, <2edit> and write the new calibration date and
the new values of PA and PM for the Q-RPT and range calibrated. If this is an Axxx Q-RPT
used in absolute mode, edit the value of P
offset
to zero. If this is an Axxx Q-RPT and the
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