Avery Dennison 9406 System Administrator Guide - Manual (Page 73)

Sum of Products
1. Place numeric data in a field. Leave the check digit slot
empty.
4 3 8 2 7 C
2. Starting with the last digit before the check digit, assign
weights, working right to left. Weights are a sequence of
numbers the same length as the field. Digits in the field
are multiplied by the weight digits to determine addends for
the check digit calculation.
When assigning weights, do not use the same number
throughout the field. Do not assign a weight to the check
digit.
4 3 8 2 7 C
6 5 4 3 2
3. Assign a number from 2 to 11 as the modulus. The
modulus will be used in the check digit calculation.
Modulus = 10
4. Multiply each digit in the field by its corresponding weight
digit.
4 3 8 2 7 C
6 5 4 3 2
_____________________________
24 15 32 6 14
5. Find the sum of the products.
24 + 15 + 32 + 6 + 14 = 91
6. Calculate the first multiple of the modulus that is greater
than or equal to the sum of the products.
10 x 10 = 100 (>91) Usi
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4. Using Check Digits
4-5