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	Technical Remarks EC, Conductivity is the parameter representing the capacity of ions in an aqueous solution to carry electrical current...... Ag/AgCl – Silver/Silver Chloride reference electrode is good for general purpose applications with a wide temperature range of -5 to 110 °C. ATC or Automatic Temperature Compensation automatically corrects the measured value based on the temperature of the solution (with use of temperature sensor). Auto-Buffer Recognition identifies and ensures correct pH buffer values are being used during calibration. Auto-CAL or Automatic Calibration frees users from cumbersome fine adjustment or manual selection of desired standards/buffer values in calibration routine. Auto-Data Logging allows measured or stored data sets being transferred seamlessly into memory or external peripherals at preset time interval or whenever readings stabilise. Auto-Ranging Capability scans and switches to the appropriate measurement range. Backlit Display offers well-contrasted backlighting on the display for optimum viewing. Barometric Pressure Compensation compensates oxygen solubility for changes in barometric pressure. Bi-Directional RS232 Linkup provides two-way RS232 communication between meter and computer via a cable to remotely control and manage meter operation. BOD or Biochemical Oxygen Demand is a measure of the amount of oxygen that is consumed by bacteria as they decompose the organic components of waste. DO measurements are usually made at the beginning and end of a five-day incubation period for a standard test. CAL-Due Prompt reminds user to calibrate the meter at set regular intervals. CE-certification or CE Marking is a conformity marking consisting of the letters “CE”. The CE Marking applies to products regulated by certain European health, safety and environmental protection legislation. The CE Marking is obligatory for products it applies to: the manufacturer affixes the marking in order to be allowed to sell his product in the European market. CE is an abbreviation for ‘Conformité Européenne’, French for ‘European Conformity’. The CE Marking indicates that the product it is affixed to conforms to all relevant essential requirements and other applicable provisions that have been imposed upon it by means of European directives, and that the product has been subject to the appropriate conformity assessment procedure(s). The essential requirements refer, among other things, to safety, public health and consumer protection. For more information, please refer to website at www.cemarking.net Cell Constant or k is the ratio of the distance between the 2 metal plates and surface area of the 2 metal plates during measurement. Cl or Chlorine is commonly used to disinfect water in pools and wastewater industry. Chlorine may be present in 2 forms – Free and Total Chlorine. Free Chlorine combines with contaminants to form Total Chlorine. The common method of measurement used by the colorimeter is based on the USEPA-approved DPD method of chlorine measurement. Conductivity is the parameter representing the capacity of ions in an aqueous solution to carry electrical current. DPD method is US EPA accepted for reporting drinking water analyses (Free and Total Chlorine) and wastewater analyses (Total Chlorine only). Please refer to the “Standard methods for the Examination of Water and Wastewater” and US EPA method 330.5 for wastewater and Standard Method 4500-Cl G for drinking water for more information. DO or Dissolved Oxygen is the measure of the amount of gaseous Oxygen (O2) dissolved in a solution. Electrode Diagnosis provides useful information on electrode condition and characteristics after each calibration. EMC or Electromagnetic Compliance is one of the CE Directives specified for electrical products. All Eutech products with CE-certification adhere to the EMC Directive. For more information, please refer to www.cemarking.net EPA or Environmental Protection Agency leads the environmental science, research, education and assessment efforts in the US. For more information, please visit www.epa.gov GLP or Good Laboratory Practices requires that time and date to be recorded with the rest of the parameters. HVAC stands for Heating, Ventilation and Air Conditioning System. IP stands for ‘Ingress Protection’. An IP number is used to specify the environmental protection of enclosures around electronic equipment. These ratings are determined by specific tests. The IP number is composed of two numbers, the first referring to the protection against solid objects and the second against liquids. The higher the number, the better the protection. Eutech products such as the CyberScan Waterproof series and Waterproof Testers have IP67 housing. The first digit ‘6’ indicates total protection against dust and second digit ‘7’ protects against the effects of immersion between 15 cm and 1 m. ISE or Ion Selective Electrode is a specialty electrode used for the measurement of ion concentration. kPA or kilopascal refers to a unit of pressure. 1 kPa is approximately the pressure exerted by a 10-g mass resting on a 1-cm2 area. 101.3 kPa = 1 atm. There are 1000 pascals in 1 kilopascal. LSD or least significant digit refers to the right-most active digit of a digital display. MTC or Manual Temperature Compensation is an alternative method for temperature compensation through the manual input of sample temperature value. ATC is more practical in most applications. Multiple-Point Calibration ensures the highest accuracy across the full measurement range. Non-Volatile Memory retains stored data and calibration information indefinitely even if power is disconnected. Normalisation Temperature is used to standardise measurements to a known ambient temperature value (generally at 20 °C or 25 °C). ORP or Oxidation Reduction Potential measurements are used to monitor chemical reactions or to determine the oxidizing or reducing properties of a solution. The ORP measurement can be made using the millivolt mode of a pH meter and are utilized very successfully in many commercial and industrial applications such as Cyanide Oxidation, Aquarium Monitoring, Chromate Reduction, Drinking Water, Swimming Pool Water, Pulp Bleaching, Cooling Tower, Ozone Monitoring and Water Pollution Monitoring. ORP is also known as Redox Potential. OUR or Oxygen Uptake Rate values are given in mg/L/hr and is usually applicable in the study of the concentration of micro-organisms. pH is the measure of H+ ion activity to determine acidity or alkalinity of test sample. In general pH 7 is neutral, below pH 7 is acidic and above pH 7 is alkaline. Theoretically pH curve is 0 to 14 pH. pH Slope is the voltage produced per pH and is theoretically 59.12mV per pH at 25 °C. However in practice it can be anywhere between 50 to 58 mV. Replatinizing is necessary when the platinum-black layer of the conductivity sensor wears off over time. The conductivity section of the sensor consists of two platinum plates or wires that are plated with a layer of “platinumblack”. Usually this is a relatively soft layer and is required for stable, accurate measurements. In time, the platinum-black layer may wear off in some applications and the sensor will require replatinising. Salinity – Salinity is the measure of amount of dissolved salts in sea water and results are reported in ppt(g/L) or %. Salinity Correction compensates the variations in oxygen solubility due to salt concentration in the sample. Self-Diagnostic Messages prompt and guide users with error message codes or graphical icons for easy meter troubleshooting. SOUR or Specific Oxygen Uptake Rate indicates biological activity of microbes in the wastewater treatment process and the load placed on them. SOUR is the relationship between oxygen uptake and the amount of solids. SOUR values are given in mg/hr/g. Stability Function averages and displays indicator or icon whenever readings stabilise. TDS or Total Dissolved Solids is measured in mg/L, parts per million (ppm) or parts per thousand (ppt). TDS Conversion Factor is a factor for converting Conductivity to TDS value to best suit the specific sample being measured (e.g. KCl = 0.5, 442 = 0.67 @ 25 °C). Temperature Coefficient indicates the temperature influence in the chemical equilibrium (eg. disassociation) of the solution due to non-linearity of intrinsic salt/chemical property varies from one sample to another (typically 2.1%/°C at 25 °C). Temperature Compensation is necessary as most electrochemical parameters (i.e. pH, Conductivity, DO) are temperature dependent and most applications require some form of temperature compensation to ensure standardized measured values. Please refer to the definitions for ATC and MTC.