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GENERAL OPERATING INFORMATION
OVERVIEW
The 2020t/i is a portable, microprocessor controlled, direct reading nephelometer. Turbidity
is measured directly according to EPA Method 180.1 or ISO Method 7027, or is calculated
ratiometrically by using a combination of the two measurements. It has a graphical liquid
crystal display and six button keypad. These allow the user to select options from the menu
driven software, to directly read test results or to review stored results of previous tests in
the data logger. The menus can be displayed in seven diff erent languages.
The 2020t/i uses a state of the art, multi-detector optical confi guration that assures long
term stability of calibrations, high precision and accuracy and low detection limits. All
readings are determined by digital signal processing algorithms, minimizing fl uctuations
in readings and enabling rapid, repeatable measurements. The microprocessor and optics
enable a dynamic range and auto-ranging over several ranges. Energy effi
cient LED light
sources are used for ISO turbidity. EPA turbidity uses a tungsten fi lament light source that
meets or exceeds EPA specifi cations and is designed for a uniform light spot image and
stable output.
A USB wall adapter, USB computer connection or lithium battery powers the 2020t/i.
GENERAL OPERATING INFORMATION
The operation of the 2020t/i is controlled by the menu driven software and user interface. A
menu is a list of choices. This allows a selection of various tasks for the 2020t/i to perform,
such as, scan blank and scan sample. The keypad is used to make menu selections that are
viewed on the display.
THE KEYPAD
This button will scroll up through a list of menu selections.
ENTER
The button is used to select choices in a menu viewed in the display.
This button controls the backlight on the display.
This button will scroll down through a list of menu selections.
EXIT
This button exits to the previous menu.
This button turns the meter on or off .
EXIT
ENTER
THE DISPLAY & MENUS
The display allows menu selections to be viewed and selected. These selections
instruct the 2020t/i to perform specifi c tasks. The menus are viewed in the display
using two general formats that are followed from one menu to the next. Each menu
is a list of choices or selections.