Thermo Electron 3-Star Conductivity, User Manual

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V-5
Orion Star Series Meter
Thermo Electron Corporation
ISE
Fresh aliquots of sample should be used at each calibration.
Prior to each day’s measurements, a two or more point calibration should be
performed and a minimum one point calibration should be performed every two
hours for the greatest accuracy.
Recommended slopes are given with electrode instructions.
It is recommended that the calibration and sample measurements be taken at
the same temperature for greater accuracy and reproducibility.
3. Place the electrode and ATC probe into the least concentrated standard for the
first calibration point.
4. Rinse well with deionized water and gently blot the electrode with a lint-free
tissue to remove water drops before moving the electrode to the next beaker.
Continue from the next lowest concentration up to the highest point to reduce
the potential effects of carryover.
Note: For greater low-level measurement accuracy, a new low-level ISE
calibration option is available. An additional rinse of the electrode with the next
standard or sample solution is recommended for any low level measurements.
▲
Autoblank Correction
Blank correction occurs automatically when calibrating with three or more
standards. This feature automatically calculates and corrects for background levels of
the species of interest.
Auto-Blank correction can be deactivated in ISE setup as described the the ISE
setup instructions.
1. Press the UP or DOWN scroll key until the ISE icon is lit.
a. Make sure the correct ISE units are displayed. If not go to the ISE setup
menu and set the correct ISE units.