Changed my mind about relay logic after talking to a building engineer at a 1970s high-rise

I used to think programmable controllers made relay logic completely obsolete. Then I was fixing a slow elevator in a downtown Seattle building last month and the head engineer walked me through the original relay bank. He showed me how a single stuck relay gave me a fault code that would have taken hours to trace on a newer board. He explained that relays fail in predictable ways and a good electrician can read the logic with a multimeter. So now I keep a spare set of relay schematics for older jobs instead of always pushing for full modernization.

2 comments

2 Comments

hill.jade1mo ago

And the best part is relays don't need software updates to keep working.

brookep271mo ago

Relays not needing software updates is honestly such a sweet deal, I feel that so hard. There's something comforting about gear that just sits there doing its job without begging for a patch.