Hach 50 71 Manual Del Usuario página 10

Conductivity cell 50 71
Introduction
The 50 71 is a platinum cell for very low conductivities
measurements.
It has 2 platinum electrodes and an integrated Pt 1000
temperature sensor.
Cell preparation
Before use for the first time immerse the electrodes in
ethanol for 15 s, and rinse with distilled water. Apply the
same procedure for a cell not being in use for long time.
Calibration
Before measurement, calibrate with standard solutions.
See User's Manual of conductivity meter.
Measurements. Recommendations
• Both, calibration and measurement must be performed
under slight stirring of standards and samples. The
stirring speed in the two cases should be identical.
• The sample must cover the measuring electrodes
• Ensure that during measurement there are not air bub-
bles over the measuring electrodes.
• After measurement, rinse the cell with distilled water or
with sample to be measured.
Warning.
The cell is made of glass, any abrupt manipulation could
break it.
Maintenance
Keep the electrodes surface clean
If the thorough rinse with distilled water is not sufficient,
suitable solvent for the elimination of sample rests can
be used. This solvent must not produce chemical attack
over the cell materials.
Inorganic contamination: Immerse the cell in diluted
hydrochloric acid or in chromic acid. Afterwards rinse
thoroughly with distilled water.
Organic contamination: Use suitable solvent (see cell's
materials), next utilize alcohol and distilled water as in
Cell preparation is described.
Do not apply any mechanical cleaning over the plati-
num cell.
Storage
Store the cell dry.
Life of the cell
The cell lifespan is unlimited if suitable maintenance is
applied and the cell does not break.
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