Glossary
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.