Replace the filling solution, Fill the probe, Storage – Hach-Lange PHC735 User Manual
Page 11
Table 4 Cleaning agent
Contaminant
Cleaning agent
Soak time
General contaminants
Electrode cleaning solution
12–16 hours
Mineral deposits
0.1 N HCl solution
10–15 minutes
Fats, grease and oils
Warm, mild detergent solution
2 hours (maximum)
Protein deposits
Pepsin cleaning solution
3 hours (maximum)
Inorganic buildup
EDTA solution
3 hours (maximum)
Replace the filling solution
Replace the filling solution and KCl crystals (if applicable) when either occurs:
•
The filling solution becomes contaminated.
•
The KCl crystals in a Red Rod probe no longer move freely through the liquid when
the probe is inverted.
1. Use a syringe or small pipette to remove as much filling solution from the probe as
possible.
2. For Red Rod probes, if KCl crystals are still in the probe:
a. Fill the probe half full with the filling solution.
b. With a finger over the filling hole, shake the probe until the crystals become
loose.
c. If the crystals will not loosen, fill the probe with filling solution. Put the probe into a
warm water bath for approximately 10 minutes (up to 60 °C (140 °F)).
d. Do step 1 again.
3. For Red Rod probes, add approximately 0.5 cm (0.2 in.) of KCl crystals to the probe
through the filling hole. For measurements at temperatures more than 60 °C (140 °F),
more crystals are necessary. Refer to
on page 2.
4. Fill the probe. Refer to
on page 11.
Fill the probe
Add filling solution to the probe when the filling solution level is low (refer to
on page 2) or is replaced (refer to
on page 11). Refer
on page 1 for the applicable filling solution.
1. If the filling hole is closed, remove the filling-hole cap from the filling hole (refer to
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 fully fill the probe.
Note: Fully fill the probe for the best performance.
5. Put the probe into storage if not used immediately (refer to
on page 11).
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. Fully dry and assemble the tip.
Storage
Short-term and long-term storage
For the best probe performance, do not let the reference junction become dry.
Note: Keep the probe in a sample for a maximum of 2 hours if the sample pH is not too high.
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