7
ISO Parameter Grade Thresholds
ISO parameter fail thresholds are set in the SV Series by commands requiring numeric settings that correlate to the parameter calculations. Following are descriptions of how the numeric calculations are divided into letter grades per the ISO Bar Code Quality Specification.
Rmin | Modulation | |
A < .5 x Rmax | A > .70 | |
F > .5 x Rmax | B > . 60 | |
C > .50 | ||
| ||
| D > .40 | |
| F < .40 |
Symbol Contrast | Decodability |
A > 70% | A > .62 |
B > 55% | B > .50 |
C > 40% | C > .37 |
D > 20% | D > .25 |
F < 20% | E < .25 |
Minimum. Edge Contrast | Defects |
A > 15% | A < .15 |
F < 15% | B < .20 |
| C < .25 |
| D < .30 |
| F > .30 |
Conversion of letter scan grade to numeric grade
A=4, B=3, C=2, D=1, F=0
Conversion of numeric symbol grade to letter symbol grade (used in aver- aging)
3.5< A < 4.0
2.5< B < 3.5
1.5< C < 2.5
0.5< D < 1.5 F < 0.5
Quick Check® SV Series User’s Guide | 7 - 1 |
