Siemens SIMATIC Vision Sensor VS 130-2 Manual page 26

Product Overview
Requirements for PDF417 codes for fast reading with guaranteed read rates up
to 5 Hz (for all sensor heads except 6GF2002-8GB)
•
The view angle of the sensor to the printed surface must be approaching
vertical (view angle 80 to 90 °).
•
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.
•
The code dimension must not be greater than 20 rows and 2 columns.
•
The bar width must be at least 6 pixels.
•
The height of individual symbol rows must be at least 18 pixels.
•
There must be no disturbances or overlaps within the code.
•
The PDF417 error correction level must be at least 1.
•
The polarity must be the same as in the trained code.
Characteristics of the PDF417 code
•
Any alignment of the code in the image
•
Up to 5 code readings per second
•
Reading inverted code images
•
Calculating the contrast quality characteristic
•
Calculating the unused error correction
•
Display of the surrounding rectangle around the code position and code mid
point
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Vision Sensor SIMATIC VS 130-2/VS 130-2vcr
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