LaMotte Tracer 1741, Руководство пользователя

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7
pH TESTING
Overview
pH is a unit of measure (ranging from 0 to 14 pH) indicating the degree of
acidity or alkalinity of a solution. pH tests are the most commonly performed
measurements in water analysis, using the negative log of the hydrogen ion
activity of a solution which is an indicator of acidity or alkalinity. Solutions
with a pH of less than 7 are considered acidic, solutions with a pH of
higher than 7 are known as bases, and solutions with a pH of exactly 7 are
considered neutral.
The pH scale is logarithmic, so, for example, if Sample A is 1 pH less than
Sample B, this means that sample A is 10 times more acidic than Sample B.
A difference of 1 pH represents a ten-fold increase or decrease in acidity.
pH Display
When the electrode is placed in a solution, the main display and bar graph
will indicate the pH reading while the lower display will read temperature.
Readings flash until they have stabilized. The bar graph is ‘center zero’, i.e. at
pH 7 there is no display. As the pH rises, the bar will move from the center to
the right. If the pH drops, the bar will move from the center to the left.
Getting Started
1. Remove the cap from the bottom of the TRACER to expose the
electrode glass surface and reference junction.
2. Before first use or after storage, soak the electrode (with cap
removed) in a pH 4 buffer or tap water for 10 minutes.
3. Before first use, hold the meter by the top battery compartment
and swiftly tap the back of the meter downward into your palm (not
a hard surface). This assures that the internal electrolyte solution
moves to the very tip of the electrode. The electrolyte should fill the
circular junction window at the tip of the electrode.
4. White KCl crystals may be present in the cap. These crystals will
dissolve in the soak or they can be rinsed off with tap water.
5. Always calibrate close to the expected measurement value.
6. A sponge is located in the electrode protective cap. Keep this sponge
soaked with a pH 4 solution to prolong the life of the electrode during
storage.