subsetbarcodezplcode128gs1-128

ZPL 2 GS1 128 barcodes - When to use/switch subsets / maximum characters

I have several questions according to the ZPL and GS1 128 Barcodes.

  1. I thought using subset B is always possible but sometimes it extends the width of the barcode more then subset C (if there are only numeric values). So I started switching between the subsets. But when does it makes sense to switch? One example:

Plain Barcode: (02)12345678901234(10)00TestTest00

Could be:
'>;>802123456789012311000>6TestTest00'
or
'>;>802123456789012311000>6TestTest>500'

  1. What are the advantages of Subset A?

  2. I also didn't find any information about the maximum of characters which can be part of a GS1 128 barcode for a specific label size (like DIN A5).

Solution

  • As a rule of thumb, I stick to Code128B with two exceptions:

    I switch to Code128C when I know I am going to have at least 6 contiguous numbers embedded in a barcode.

    I use Code128A when I can't get around embedding tabs or carriage returns in a single symbol (when I'm trying to simulate a user filling out multiple fields on a form with one scan), but seldom for access to other control codes..

    Maximum characters for GS1 fields can be found here: https://en.wikipedia.org/wiki/GS1-128

    It appears that most fields are limited, but many allow up to 30 characters. With one exception (Extended Packaging URL), which allows up to 70 characters.

    As far as label size, that's all about bar density. My tightest scannable 70 character symbol is about 4 inches long, assuming the use of Code128B.