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6.2 CARE OF YOUR PROBE AND CABLES
The probes do not require any maintenance; they do not need recharging and are sealed for life. Any mud
or grit should be removed from the electrode by swirling the electrode back and forth in a container of warm,
soapy water and then brushing with a wet rag. The soapy water will not harm or contaminate the electrode.
Always check that the connecting cables are free of damage such as cuts and tears in the sheathing before
use.
The Copper-Copper Sulphate half-cell probe is intentionally filled
with a reserve of saturated Cupric Sulfate solution combined with
solid Cupric Sulfate crystals to ensure a minimum 10-year design life.
Under certain circumstances a very small percentage of this reserve
can leach out from the ceramic sensing tip of the half-cell producing
crystals as shown in the photograph.
This does not affect the performance of the cell. The crystals should
be removed by washing in distilled water.
6.3 TEMPERATURE
Do not allow the probe to freeze. Although freezing will not damage your probe, it will be impossible to obtain
reliable measurements while in this state. All measurements are affected by temperature; if you take two
readings in identical conditions, one in the summer at 29°C (85°F) and the other in the winter at 1°C (34°F),
the half-cell potential readings will be different.
Each probe is tested at 25°C to be within ±10 mV of a standard Calomel reference cell. The following values
relative to a standard Calomel cell are used as the test limits during manufacture:
331_T_00_04.book Page 21 Thursday, March 12, 2009 10:05 PM
