Version 1.5 August 2001
4
Care of the Conductivity/TDS Cell
To prepare the cell, remove any outer protective sheath that may be used in shipping.
1. Cell
Storage
On sheathed cells, replace the sheath over the cell when storing. For non-sheathed
versions, soak the cell tip in de-ionized water for storage.
2. Cell
Cleaning
After each use, the cell tip should be rinsed with de-ionized water. If solids build up
inside the cell carefully remove with a cotton swab soaked in solvent taking care not
to touch the metal parts of the inner cell.
3.
Internal Cell Elements
Two platinum plates reside on the inner cell wall. These plates should be a uniform
black color. If blemishes and scratches appear on these plates, the cell may need
repair. If this occurs, it is suggested that the cell be returned for evaluation.
Care of the pH Electrode
1.
The 60120B pH electrode is recessed in the polymer body allowing it to rest against
the bottom of a beaker without damage the glass bulb. This eliminates the need for
electrode holders and allows the probe to be used as a stirring rod. The sealed
reference design eliminates the need for filling solutions (minimizes "dry-out"). Up to
100 psig systems can be accommodated without external pressurization.
2.
The Electrode should remain in its bottle or cap until used. Afterwards, store the
Electrode in its bottle. Use a pH 4 buffer solution or tap water as the storage medium.
3.
If bubbles are seen in the bulb area, hold the electrode by its cap and shake
downwards until bubbles are removed.
4.
To improve speed of response, vigorously stir the electrode in the sample, buffer, or
rinse solution.
5.
After exposure to a sample, buffer, or rinse solution, shake the electrode with a snap
motion to remove residual drops of solution.
6.
Use part of the next sample/buffer to be measured as a rinse solution, when possible.
7.
When calibrating, use a buffer as close as possible to the expected pH of the sample.
8.
Keep buffers and samples at the same temperature to avoid temperature effects.
9.
pH readings stabilize faster in some solutions than others; allow time to stabilize.
10. Electrodes deteriorate over time. If accuracy falls to 10% the electrode should be
cleaned or replaced. If no improvement is observed, replace the electrode at once.
Electrode Storage
The electrode can be stored in the soaker bottle or wetting cap. For the storage bottle,
slide the cover onto the electrode, replace the O-ring, and insert electrode into bottle firmly
tightening the cap. Ensure that the bottle or cap is filled with a pH 4 buffer or tap water.
Electrode Cleaning
The type of electrode coating which occurs over time will determine the cleaning method.
Soft coatings can be removed by vigorous stirring or by the use of a squirt bottle. Organic
chemical (hard coatings) should be chemically removed. Only in extreme cases should the
bulb be cleaned mechanically.
