Siemens SIMATIC MV540 H, Руководство по эксплуатации

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Image processing
3.2 Code verification
SIMATIC MV500
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Operating Instructions, 06/2018, C79000-G8976-C494-01
3.2.2 Grading
Quality levels
The verifier reports the marking quality in five grades known as "quality levels".
Older verifiers identify these grades based on a single letter A to F (without E) with F being
the lowest quality level. Verifiers of the newer generations identify the value range
numerically from 4 to 0 with 0 being the lowest quality level.
With the verifiers of the SIMATIC MV500 series, you can choose either of the quality grading
systems.
Evaluation
The classification is specified in the WBM as a value from 4 to 0 (or A to F without E). In
addition, each quality grade is assigned one of three ratings (good [G] / fair [F] / poor [P]).
This classification not only allows fast visual checks of the quality using the color coding of
the display, but also automatic rejection of the read result as "N_OK" if it falls below a certain
quality threshold.
Table 3- 1 Quality levels
Grade Grade (old) Defaults for quality grading Representation in the user
interface
Defaults for the read result
4 A Good Green = [G]ood OK
3 B Can be set specifically by
user
1)
2 C Can be set specifically by
user
1)
Yellow = [F]air OK
1 D Can be set specifically by
user
1)
Red = [P]oor N_OK
(Can be set for specific us-
ers)
0 F Poor
1)
The user-specific setting is only for ascending or descending order.
Example
In an application in which only very good markings are acceptable, all grades below 4 are set
to "Poor". This allows the rejection of all unacceptable specimens.
3.2.3 Verification of printed labels
In 1996, the "Association for Automatic Identification and Mobility" (AIM) published the data
matrix symbology specification with an evaluation procedure for print quality. According to
this evaluation procedure, test systems could evaluate a symbol according to its degree of
acceptability (4 to 0).
The specification later became the ISO/IEC 16022 standard. This type of test was developed
for paper labels with high contrast.