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Unformatted text preview: At temperatures of over 80 °C plastic
can be affected permanently, unsuitable reflectors can limit the range and
effectiveness considerably. 6.3.4 Examples of application Fig. 6.3.3: Monitoring build-up and counting of objects by means of retro-reflective sensors Advantage 84 Only the passive reflector is required on one side of the conveyor without the need
for electrical cabling for the receiver of a through-beam sensor. © Festo Didactic GmbH & Co. KG • FP 1110 6. Optical proximity sensors Fig. 6.3.4: Slack control by means of retro-reflective sensors Reflector Reflective foil or individual triple reflectors
The solution shown in Fig. 6.3.4 is not applicable in the case of transparent material. 6.4
Diffuse sensors 6.4.1 Function description
The emitter and receiver are fitted in the same housing. The object diffusely reflects
a percentage of the emitted light thereby activating the receiver. Depending on the
design of the receiver, the output is then switched through (normally open function)
or switched off (normally closed function). The switching distance largely depends
on the reflectivity o...
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- Spring '12