Hach-Lange ISENa38103 - Manual (Page 11)

6. Select Acceptance Criteria and update the settings:
Option Description
Acceptance Limits Sets the tolerance limits for check standard—1% to 20%.
Cal Expires on Failure Recalibration required if check standard fails—Yes or No.
The calibration expires if the check standard fails and Cal Expires is
set to Yes.
7. If prompted, enter a name for the new method settings. Additional changes made to
the settings of an existing method are automatically saved with the same method
name.
8. Push EXIT until the meter returns to the measurement mode.
Maintenance
Clean the probe
Clean the probe when:
• Drifting/inaccurate readings occur as a result of contamination on the glass sensor or
the probe being left dry for extended periods of time.
• Slow stabilization time occurs as a result of contamination on the glass sensor.
• The slope is out of range as a result of contamination on the glass sensor.
For general contaminants:
1. Rinse the probe with ISA rinse solution and blot dry with a lint-free cloth.
2. Soak the glass bulb for 12 to 16 hours in Hach Electrode Cleaning Solution.
3. Rinse or soak the probe for 1 minute in 25 mL of 100 mg/L sodium standard (that
contains Sodium ISA).
4. Soak the probe in pH 4 buffer for up to 20 minutes, then rinse with deionized water.
5. Calibrate and test the probe again using the measurement procedures.
Fill the probe
To add filling solution to the probe:
1. If the filling hole is closed, remove the filling-hole cap from the filling hole (refer to
Figure 1 on page 2).
2. Remove the cap from the tip of the filling solution bottle.
3. Hold the bottle so that the tip is down. Put the tip of the bottle in the filling hole.
4. Slowly squeeze the bottle and fill the probe completely.
Note: Fill the probe completely for the best performance.
5. If the probe will not be used immediately, store the probe (refer to Storage
on page 12).
6. Keep the filling solution bottle and cap for later use.
Note: If the dispensing tip becomes clogged, remove the dispensing tip and soak the tip in
warm water. Dry thoroughly and assemble.
Prepare the ISA rinse solution
To prepare the ISA rinse solution, add one Sodium Ionic Strength Adjustor (ISA) powder
pillow (0.4 g) to every 25 mL of deionized water. Put the ISA rinse solution in a rinse
bottle.
Prepare the storage solution
To prepare the storage solution, add one Sodium Ionic Strength Adjustor (ISA) powder
pillow (0.4 g) to 25 mL of 100 mg/L Na+ standard solution.
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