I'll never do PLC work again. Forget undocumented code, most of the time there's no schematics for the hardware you're working on because it was custom-built thirty years ago.
My company is generally good about that. We have lots of overlapping documentation that answers questions like that in different ways. From Electrical schemas to QA docs, picture archives of panels and wiring, ticketing systems, spreadsheets over I/O, etc. etc.
I hate PLC work for other reasons. I'm starting to look at going back to more traditional software role. I'm a bit tired of the road work and find the compensation for the amount asked of you to be drastically underwhelming. This meme is very much relevant:
I hate PLC work for other reasons. I'm starting to look at going back to more traditional software role. I'm a bit tired of the road work and find the compensation for the amount asked of you to be drastically underwhelming. This meme is very much relevant:
https://i.redd.it/rawo5uki1v9b1.jpg