Myron L 729II - Manual (Page 69)

65
IX. GLOSSARY
442™ An Internationally recognized “natural water” standard developed by the Myron L Company in 1964.
Algorithm A procedure for solving a mathematical problem. See Addendum, Temperature Compensation and TDS
Derivation.
Anions Negatively charged ions
DVM Digital Volt Meter
Hysteresis Dead Band — related to alarm setpoint. The amount of delay or overlap between change from high to low or low
to high.
LCD Liquid Crystal Display
KCl Potassium Chloride — used as a standard for many applications. Normally, micromhos or microsiemens are the
units of measure.
NaCl Sodium Chloride — used as a standard for sea water and other applications.
NIST National Institute Standards & Testing
PLC Programmable Logic Controller
PPM Parts Per Million — common units of measure for TDS.
PPT Parts Per Thousand — common units of measure for TDS.
SCADA Supervisory Control And Data Acquisition
Tempco (TC) Temperature Compensation — See Addendum, Temperature Compensation.
TDS Total Dissolved Solids or the Total Conductive Ions in a solution — normally displayed as ppm or ppt. See
Addendum, Conductivity Conversion to TDS.
Tweaker A screwdriver specially designed for adjusting electrical calibration controls.
µM or µS Micromho or microsiemen — common unit of measure for conductivity.
MegΩ Megohm — common unit of measurement for resistivity.
USP25 United States Pharmaceutical regulation, revision number 25. In part, requires Conductivity/TDS, resistivity or
pH measurements be taken, recorded and/or systems controlled using equipment without temperature
compensation. Requires a separate temperature measuring device (temperature measurements may be part of
Cond/TDS, Resistivity or pH device but must not correct measurements for temperature errors).