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FEATURES
Auto-Bu
ff
er Recognition
Yes ( CON 6 PLUS)
Hold Function
Yes “HO”
Low Battery Indicator
Yes “LO”
Auto Shut O
ff
20 minutes after last key operation
Display
Custom LCD
Operating Temperature
0 to 50 °C
Power Requirements
(4) AAA alkaline batteries (included)
Battery Life
>100 hours
Meter Dimensions / Weight
15.7 x 8.5 x 4.2 cm / 255 g
9. CONDUCTIVITY THEORY
Conductance is a quantity associated with the ability of primarily
aqueous solutions to carry an electrical current (I) between two metallic
electrodes when a voltage (E) is connected to them. Though water itself
is a rather poor conductor of electricity, the presence of ions in the
water increases its conductance considerably, the current being carried
by the migration of the dissolved ions. This is a clear distinction from
the conduction of current through metal, which results from electron
transport.
The conductance of a solution is proportional to and a good, though non-
speci
fi
c indicator of the concentration of ionic species present, as well as
their charge and mobility. It is intuitive that higher concentrations of ions
in a liquid will conduct more current. Conductance derives from Ohms
law, E = IR, and is de
fi
ned as the reciprocal of the electrical resistance of
a solution.
C=1/R
where C is conductance (siemens)
R is resistance (ohms)
One can combine Ohms law with the de
fi
nition of conductance, and the
resulting relationship is:
C=I/E
where I is current (amps)
E is potential (volts)
