7. MAINTENANCE OF TRACEABILITY AND RECALIBRATION
Page 173
© 2007 DH Instruments, a Fluke Company
If a full adjustment is desired, at least two points should be selected within the range
of the sensor and encompass the range of measurements the sensor may
encounter during normal operation.
To adjust the values of the Adder and/or the Multiplier use GFS Tools and select
the
[Setup]
,
[Calibration]
,
<Ambient>
tab (see Figure 111) to access a screen
in which the values of the Adder and Multiplier can be edited. For a one point
verification only the Adder should be adjusted. From here, press
OK
and wait
while the coefficients are uploaded to the LCM. When the upload is complete,
cycle the power on the LCM, and the LCM enclosure sensor reading should
reflect the newly applied calibration coefficients.
See
Section
7.5.4 for an explanation of Adders and Multipliers and their use in
adjusting internal sensors.
See Section 1.1 for enclosure pressure sensor specifications.
Figure 111.
Ambient sensors adjustment tab
7.5.4.3
AMBIENT TEMPERATURE SENSOR
PURPOSE
To view and adjust the output of the ambient temperature PRT.
The ambient temperature sensor and External PRT temperature sensor are of
the same technology and read in the same manner. However, their recommended
calibration procedures differ reflecting the different measurement uncertainty
specifications of the two measurements. See Section 1.6 for recommended
calibration procedure on the External PRT temperature sensor, which is used to
measure temperature with much lower uncertainty.