My advice, when working on someone else's program in 500, create a new data register for each data type you use, so instead of B3, N7, F8, etc. You can find all the data tables in the program tree to the left, they'll be labeled. Those are predefined with a single letter nomenclature as another poster said. However, don't look for things like controller or program tags. I actually kind of prefer Logix 500 because it's so simple. 500 is just a low memory version of 5000, basically. The actual logic itself is the exact same. Please click "report" on spam Related sub-reddits:
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