Siemens SIMATIC Vision Sensor VS 130-2 Manual page 22

Product Overview
The following figure shows you a legal constellation for guaranteed read rates: All
neighboring objects are clearly of a different size from the code. In this case,
rotation of the code from exposure to exposure would be acceptable since there is
no rectangle of another object that is compatible with the largest possible rectangle
around the code.
Note
Operating and monitoring via the setup support can lead to longer cycle times.
Processing Method for Fast Reading of Data Matrix Codes with a Guaranteed
Read Rate of 20Hz
Settings:
•
Speed = high
•
Exposure = manual (due to the short processing times, automatic exposure is
not possible with this method.)
These read rates are achieved under the following conditions:
•
The illumination must be stable enough so that automatic shutter control is not
necessary.
•
The code dimension must not be greater than 20 x 20 dots.
•
Since the image is recorded "undersampled", the dots of the code must have a
minimum size of 10 pixels
•
The code must be positioned in the sensor image so that there is always a
clearance of at least 3 dots to the edge of the image.
•
The code must not make contact with any other objects in the image, the quiet
zone must be kept free.
•
To allow the code to be found quickly, there must be no other objects (bus
structures count here as well) in the image with enclosed rectangle and of a
comparable size to the trained code. (See also the two following figures.)
•
The diameter of the dots must be uniform over the entire code field. The
contrast between dots and the background must be approximately the same
over the entire code field.
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Vision Sensor SIMATIC VS 130-2/VS 130-2vcr
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