8
LaMotte TRACER pH PockeTester
TM
1741 Instruction
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
fl ash 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
fi rst use or after storage, soak the electrode (with cap removed) in a
pH 4 buffer or tap water for 10 minutes.
3. Before
fi rst 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 fi ll 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.
