Arrangement for determining the presence of specific substances in a liquid

摘要

A simple and sensitive arrangement for determining the presence of specific substances in a liquid is provided for determining the presence of oil in water. The arrangement comprises a light source which emits diffused UV light through the liquid to be tested, a detector which receives the UV light, and a processing circuit which is driven with a measured signal from the detector. The processing circuit generates an alarm signal if the measurement signal which increases with intensity of the detected UV light becomes smaller than the predetermined value.