SICK LMC121, Руководство по эксплуатации

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Product description
42
© SICK AG · Germany · All rights reserved · Subject to change without notice
8012471/ZN27/2017-06-09
Operating Instructions
LMS1xx Laser Measurement Sensors
Chapter 3
Evaluation strategy
In SOPAS ET choose one of four possible evaluation strategies:

Pixel evaluation

The LMS1xx evaluates the entire area of the field, every single beam is considered in
the evaluation. If an object enters the field, this result is sent to the related output.

Blanking

The LMS1xx evaluates the entire area of the field. However, using blanking objects of a
specific size can be blanked. An object is only detected if it is larger than the blanking
configured.

Contour

The LMS1xx evaluates the presence of a contour that must be permanently and
completely in the evaluation field. As a result the LMS1xx can detect, e.g., that a door
is opening outwards or that the position of the LMS1xx is being changed. Also crawling
beneath a vertical evaluation field or the deflection of the laser beam by a mirror can
be detected.
Using blanking the lack of part of a contour can be blanked up to a certain size.

I/O operator

Using the I/O operator evaluation strategy you can link the inputs of the LMS1xx with its
outputs (see
section 3.10.5 “Logical operators for inputs and outputs” on page 46 ).
Response time
For the Pixel evaluation, Blanking and Contour evaluation strategies you must define a
response time. For the LMS1xx to detect an object using the Pixel evaluation or Blanking
evaluation strategy, the object must be detected in one place for at least the duration of the
response time. For the Contour evaluation strategy the contour infringement must be
detected in one place for at least the duration of the response time.
Obstruction protection
If pixel evaluation is configured, glare may result in it no longer being possible for the
LMS1xx to monitor a field. If blanking is configured, small objects in the near range of the
LMS1xx can cause large shadows.
If you use evaluation fields at a distance from the LMS1xx, then the object or the object
erroneously measured due to glare is outside the evaluation field and will not be detected.