Integrated Multi-parameter Sensor Operation manual
11
Safety Cautions
Hazardous film factors are: chemicals (organic solvents, acids and peroxides); mechanical damage (impac
t, friction or tear)
Figure 7 Dissolved Oxygen Sensor
DO Sensor Specification
Principle
Fluorescence method
Range
0-20 mg/L
；
0-20 ppm
；
0-200%
Resolution
0.1%/0.01mg/L
Accuracy
±
3% or
±
0.3mg/l of Measured Value
，
take the greater
value
2.6 Turbidity Sensor
Principle:
Turbidity is the measure of the amount of suspended solids in water. Suspended solids in water are
generally clay, sand, colloidal matter, algae, plankton and microorganisms.
The turbidity sensor is designed based on a combined infrared absorption scatter ray method. The infrared
light emitted by the light source is scattered by the particles in the water to be measured, converted into
an electrical signal by a photo detector, and subjected to analog and digital signal processing to obtain a
turbidity value of the water sample. A turbidity unit NTU having a basic turbidity standard using formalin
(a white polymer produced by polymerization of a certain amount of barium sulfate and hexamethylamine)
is usually used. The turbidity sensor is shown in Figure 8.