Operating Instructions - CPA2501
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Air Data Test Indicator
CPA2501
as the “High Reference” value in the same manner.
After all four values (High Reference, High Reading, Low reference, & Low reading) have been entered,
the Adjust button will become active. Press the Adjust button to check and accept the calibration data
then press the Save button. The instrument will then prompt with the question “Save Cal Data?”. Pressing
the check mark [
] in this screen will save the calibration to the memory of the transducer.
10.9 Linearization
The Linearize Application provides a place to record upscale and downscale calibration data
and to linearize each transducer using that data. An “as found calibration” can be performed by
connecting a suitable pressure standard to the Pressure port of the transducer being calibrated,
and supplying all 11 pressure points across the complete range. The record of the pressures
from the pressure standard and the corresponding reading from the instrument’s transducer can
be recorded and transcribed into the Linearization Matrix shown in Figure 10.9-A. Linearization
of each transducer can be performed from this screen by selecting each transducer channel
using the channel button in the top left hand corner.
Figure 10.9-A - Linearization Application Data Matrix
The Linearization Application automatically populates the screen with 10% increments from the low to
high pressure corresponding to the range of the transducer selected. These values can be changed to
reflect the values generated by the standard and the corresponding readings taken from the CPA2501.
Each value from the standard can be entered under the reference column, corresponding Upscale and
Downscale readings from the instrument can be entered in the “Upscale” and “Downscale” columns. To
enter a value simply press the number and a key pad will appear (see Figure 10.9-B) where the number
can be entered. Press the check mark [
] to accept each value. The “Average” column automatically
averages the upscale and downscale values.
