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VII. CALIBRATION INSTRUCTIONS
A.
General Information
SENSOR MODULE CALIBRATION -
The 90XL display module does not require
calibration, although the menu options on the display module are used to calibrate the
connected measurement sensor modules. Mesa recommends that users verify sensor
modules values against non-expired NIST-traceable solutions before use and calibrate
(adjust) the meter only when these verifications are out of tolerance.
NOTE:
Yearly factory calibrations are recommended on the Conductivity/Temperature
and Pressure sensor modules. Factory Calibrations stickers are located on the sensor
module and contain last known calibration date and calibration due date.
CAUTION:
Always use reference standards that are traceable to the National Institute
of Standards and Technology (N.I.S.T.). Mesa Laboratories reference solutions are highly
recommended and are the same solutions used in the manufacture and factory
calibration of your instrument. DO NOT use expired or out of date Solutions
.
CAUTION:
Use only sodium chloride (NaCl) conductivity standard solution. The
conductivity/ temperature sensor module is temperature-compensated for NaCl solution.
Other solutions, such as potassium chloride (KCl), may result in inaccurate calibration.
NOTE:
Select the sensor module that you plan to calibrate by scrolling to it on the MAIN
screen. When CALIBRATION is selected from the MENU screen, all procedural and on-
line help information will be related only to the type of sensor module that was selected.
B.
Resetting Factory Defaults (Applies to all module types)
This procedure may be selected from the calibration menu and, when performed, will
set the selected sensor module back to its original factory calibration state.
If this option is selected, the screen at the right will appear for the user to confirm that this
is the procedure desired (YES) or return to the MAIN screen (MAIN or NO) to begin
again.
WARNING:
Always verify calibration sensor module calibration after performing this
procedure and prior to taking any measurements.