Question

What is the difference between 'Light-on' and 'Dark-on'?

Answer

This refers to if the photosensor is detecting its own light source when its normal output is 'on'. A diffuse sensor is normally 'light-on', since its output is on when its own light source is reflected from a target. Retroreflective and thru-beam sensors are normally 'dark-on', since the output is active when the light beam is blocked. Note that several sensors may be configured to either a 'light-on' or 'dark-on' mode of operation.

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FAQ Subcategory: None

This item was last updated on 2009-12-08
Document ID: 1281

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