Myron L TechPro II, Operation Manual

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D. Soft Protective Carry Cases
Padded Nylon carrying case features a belt clip for hands-free mobility.
Two colors to choose from;
Blue - Model #: UCC
Desert Tan - Model #: UCCDT
E. Hard Protective Carry Cases
Large case with 2 oz. bottles of calibration Standard Solutions (KCl-7000,
442-3000, 4, 7, & 10 pH buffers and pH storage solution) -
Model #: PKUU
Small case (no calibration Standard Solutions) - Model #: UPP
F. Replacement pH Sensor (TPH1)
pH sensor is gel filled and features a unique porous liquid junction. It is
user-replaceable and comes with easy to follow instructions.
Model #: RPG
XVII. TEMPERATURE COMPENSATION (Tempco)
of Aqueous Solutions (TPH1 & TP1)
Electrical conductivity indicates solution concentration and ionization
of the dissolved material. Since temperature greatly affects ionization,
conductivity measurements are temperature dependent and are normally
corrected to read what they would be at 25°C.
A. Standardized to 25°C
Conductivity is measured with great accuracy in the TechPro II using a
method that ignores fill level, electrolysis, electrode characteristics, etc.,
and features a unique circuit to perform temperature compensation. In
simpler instruments, conductivity values are usually assigned an average
correction similar to that of KCl solutions for correction to 25°C. The
correction to an equivalent KCl solution is a standard set by chemists
that standardizes the measurements and allows calibration with precise
KCl solutions. In the TechPro II , this correction can be set to either KCl,
NaCl or 442 to best match your applications.
B. Tempco Variation
Most conductivity instruments use an approximation of the
temperature characteristics of solutions, perhaps even assuming
a constant value. The value for KCl is often quoted simply as
2%/°C. In fact, KCl tempco varies with concentration and temperature
in a non-linear fashion. Other solutions have more variation still. The
TechPro II uses corrections that change with concentration and
temperature instead of single average values. (see Chart 1 on pg. 26).