ISE
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10. ISE
10.1. PREPARATION
One or two-point calibration can be performed with a choice of 6 standard solutions
(0.01, 0.1, 1, 10, 100 and 1000 ppm).
1. In Setup menu select the proper ion charge (see SETUP section for details).
Note:
When “UndF” option is selected, a two‑point calibration must be performed.
If exiting calibration after first standard is confirmed, the LCD displays “‑‑‑‑”.
2. Prepare two clean beakers. One beaker is for rinsing and one for calibration.
3. Pour small quantities of standard solution into each beaker.
4. Remove the protective cap and rinse the probe with solution used for the first
calibration point.
If necessary, press RANGE until the display changes to ISE measurement range.
10.2. CALIBRATION
For better accuracy frequent calibrations are recommended. The ISE range should be
recalibrated at least once a week, or:
y
whenever the ISE probe or ion charge is changed
y
after testing aggressive samples
y
when high accuracy is required
Due to electrode conditioning time, the electrode must be kept immersed a few seconds
to stabilize.
Procedure
1. Immerse the probe approximately 4 cm (1 ½”) into the selected solution and stir gently.
2. Press CAL. The CAL, BUFFER, CALIBRATION tags, the calibration point number and the
standard value (0.010) are displayed along with WAIT tag blinking. If needed, press the
keys to select a different standard.
