Introduction - novomatics Turbitronic P Operation Manual

Novomatics Manual Turbitronic P
2.

Introduction

This chapter is providing information on the basic concept of the turbidity measurements.
Turbidity is defined as an optical property of a liquid caused by light scattering and absorption.
This state will be caused by unsolved particles, for instance fine polymers or organic material.
These particles solved in a liquid lead to haze or turbidity, if the light falls through the liquid.
Easily said, turbidity is the opposite of clearness.
In the past, the turbidity detection could be determined on the manual way only. This test
method had many sources of error and uncertainty due to poor reproducibility, variances in
heating and cooling of the sample, inaccurate turbidity determination, etc.
As the turbidity measurement must be combined with the temperature measurement in case of
the Turbitronic P, a special white LED photocell-system has been designed. This fiberglass
photocell-system measures the absorption of the white light beam passing through the test tube.
This makes the photocell more sensitive for low turbidity measurements.
The output signal of the photocell detection circuit decreases non-linear with increasing turbidity
within the relevant turbidity range. The instrument is factory calibrated for turbidity but the
operator is requested to approve it periodically. The user can determine which turbidity value is
recognized as the cloud or clear point by program definition.
The photocell-system for turbidity measurement in the Turbitronic P has proven to be a rugged
and reliable device, designed for continuous use in factory environment.
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