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sensors can cause an interruption of the light beam. This then continually feigns the
presence of an object. In the case of diffuse sensors, heavy contamination of the
lens system can be evaluated as an object present, if the light emission is reflected
back to the receiver as a result of the contamination of the lens. Heavy
contamination of the object itself can lead to the evaluation of an object not present,
if less light is reflected as a result of contamination.
In order to achieve reliable operation, the following measures should be taken:
1. Operating the optical proximity sensor with sufficient operating margin.
– Carrying out pre-trials.
– Selecting a suitable proximity sensor with sufficient operating margin.
2. Using proximity sensors with setting aids, e.g. flashing LED function in marginal
3. Using proximity sensors with an automatic contamination warning signal. Optical proximity sensors have a certain operating margin (also known as function
reserve) β, being the quotient of the actual optical sign...
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This note was uploaded on 11/01/2012 for the course CHEMICAL 102 taught by Professor Jamesrodriguez during the Spring '12 term at Universidad Politécnica de Cartagena.
- Spring '12