Normalizing The Reader - Siemens SIMATIC MV440 Operating Instructions Manual

4.2.6.1

Normalizing the reader

During normalization of the reader, the reaction of individual cameras in various lighting
surroundings and under various lighting conditions is set directly proportional to the contrast.
Brightness offset, gain and exposure time of the camera are set to achieve this linear
response.
Procedure
Normalize the reader as follows:
1. Make sure that you have stable and uniform illumination of the working area of the
reader, in particular the surrounding lighting. Refer also to the introductory remarks in
"Calibration and activating verification".
2. Place the calibration plate in the viewing range of the reader.
3. Position the black square in the center below the reader.
Note: If, during processing, the code to be read is always positioned in a region below the
reader that is clearly offset from the center, you should also position the black square in
this region.
4. Position the frame around the square so that it surrounds the entire square with a narrow
white margin on each side.
5. If required to meet the requirements of your application, configure the maximum exposure
time and brightness. To achieve a good image quality, the maximum brightness for the
verification is more restricted than when using the device as a reader.
6. Start the normalization and, if necessary, follow the instructions for eliminating errors.
See also
Warnings and notes (Page 339)
SIMATIC MV420 / SIMATIC MV440
Operating Instructions, 04/2013, A5E02371045-06
Image processing
4.2 Code verification
63