Swapped out my old relay logic for a PLC on a 1980s Otis last winter

I used to patch together replacement relays and timers on these old units because that's what I learned, but after a three day fix turned into a week of chasing bad contacts I finally bit the bullet and learned basic ladder logic. Now I can diagnose most issues from the controller with a laptop instead of crawling around with a meter, and it cut my callbacks in half. Has anyone else made that switch and found a good way to convince old school guys to give PLCs a try?

2 comments

2 Comments

tyler6141mo agoTop Commenter

Whoa wait... three days of crawling around with a meter? That's brutal man. I respect the grind but I don't think I could have stuck with relays that long.

jade321mo agoMost Upvoted

You seriously wouldn't have stuck with it for three days? Bro, that's exactly why most people never actually find the real problems. They quit too early and end up just guessing at fixes that don't work. Crawling around in an attic or a hot basement for hours sucks, but it beats coming back next week because you missed something. Plus, I learned more about that building's wiring in three days than any blueprint could tell me. Sometimes you just gotta embrace the suck and get it done right.