Hanna Instruments HI 88703 User Manual

Page 5

ABBREVIATIONS

NTU

Nephelometric Turbidity Units

JTU

Jackson Turbidity Units

FTU

Formazin Turbidity Units

USEPA US Environmental Protection Agency
LCD

Liquid Crystal Display

RTC

Real Time Clock

Relative Humidity

Identification

EBC

European Brewery Comitee

Turbidity is the optical property that causes light to be scattered and absorbed, rather than transmitted.
The scattering of the light that passes through a liquid is primarily caused by the suspended solids.
The higher the turbidity, the greater the amount of scattered light. Because even the molecules in a
very pure fluid scatter light to a certain degree, no solution will have zero turbidity.
The

USEPA Method 180.1 specify the key parameters for the optical system to measure turbidity

for drinking, saline and surface water in a 0 to 40 NTU range, using the nephelometric method.
The

HI 88703 instrument is designed to meet or exceed the criteria specified by the USEPA Method

180.1 and Standard Method 2130 B.
The light beam that passes through the sample is scattered in all directions. The intensity and pattern
of the scattered light is affected by many variables like wavelenght of the incident light, particle size
and shape, refractive index and color.
The optical system includes a tungsten filament lamp, a scattered light detector (90

) and a

transmitted light detector (180

PRINCIPLE OF OPERATION

HI 88703 has a user-friendly interface with an easy to understand, graphical LCD. All messages are
in plain text, easy to read and understand. Comprehensive contextual help is available at a simple
key press. All messages and helps are available in several languages. Confirmation and error acoustic
signals help the user during instrument operation. Furthermore, a tutorial mode of operation guides
the user step by step through the analysis process.
The instrument’s logging function offers complete information for the measurement. Up to 200
measurements can be stored in the internal memory and consulted at any time. In order to further
store or analyse, the data can be downloaded to a PC using the USB port.