32
CALIBRA
TION
Procedure
• Select the ISE probe in SETUP menu or the Ion Charge (see METER SETUP section for details).
Note:
If ISE probe is not calibrated in at least one point, “
----
” is displayed.
• Pour small, volumetrically measured 50 mL of calibration standard solutions and transfer into clean
beakers. If possible, use plastic beakers to minimize any EMC interferences. For accurate calibration
and to minimize cross-contamination, use two beakers for each standard solution: one for rinsing
the electrode and one for calibration.
• There are six memorized standard solutions: 0.1, 1, 10, 100, 1000, 10000 ppm and up to five
point calibration can be performed. For fluoride electrode, the 2 ppm standard is also available.
• Remove the protective cap from the ISE electrode.
Five-Point Calibration
1. Immerse the ISE electrode approximately 4 cm (1½”) into the less concentrated standard
solution and stir gently.
2. Press
CAL
. The LCD displays the ion concentration in the selected unit or “----” if not calibrated.
If necessary, press the / keys to select a different standard value.
The “ “ tag is displayed blinking until the reading has stabilized. When the reading is stable
and within range of the selected standard, the
CFM
functional key is displayed.
