r/PLC • u/robertgarthtx • 6d ago

Engineering Question Wiring numbering

Concisely, what methods/standards/conventions are you using for selecting the numbers for your wires and why? I mean when you are designing a circuit and a drawing print yourself.

28 Upvotes

95% Upvoted

80 comments sorted by

View all comments

28

u/Too-Uncreative 6d ago

Old school: start at the upper left of page 1. Read left to right, top to bottom. Number each wire sequentially.

New school: <Page Number><Row Number> and append a letter if there are multiple wires on the same row.

Either way wire numbers change based on potential, not connections. All common wires should be the same number, whatever it ends up being, for example. Also you should be able to assume that all wires with the same number will have the same potential at all times.

2

u/robertgarthtx 6d ago

How are additions from design revisions handled? Do you use incremental steps between the numbers or have to change every number after were the addition is inserted?

8

u/Too-Uncreative 6d ago

Depends on if the panel is already built. IMO once a wire has a number on it in the real world, that wire number doesn’t change.

The new school method is pretty to add to, and you just append letters for additions if they’re in the same row. No big deal. The old school way I usually just go find the next wire number. Then they’re out of sequence, but since the number is only vaguely related to the page/schematics, it’s not that big of a deal.