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What they do:
Light curtains are an advanced method of safeguarding personnel around many hazardous machines. They are more efficient than customary measures, such as sliding gates, mechanical barriers, etc.
Essentially, they are an active optoelectronic device which contains one or more transmitting elements and one or more receiving elements which together form a sensing field.
Primary Types and How They Work:
Light machines have different conditions and modes under which they operate. Depending on the need and the condition in which it is specified.
A photoelectric transmitter projects an array of synchronized parallel infrared light beams to a receiver unit. When an opaque object interrupts one or more of the beams the control logic of the curtain sends a stop signal to the guarded machine. The transmitter unit contains LEDs which emit pulses of the invisible infrared light when energized by the curtains timing and logic circuitry.
The control logic, user controls and diagnostic indicators may be contained in a separate enclosure or be enclosed in the same housing as the receiver.
They are often categorized by the type of guarding they require ie: Minimum Safe Distance, Primary Control Elements,
Operation
Range
, etc.
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