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dimonium_anonimo t1_iy3tbcu wrote

Reply to comment by Toes14 in Eli5 why do traffic lights have red, yellow and green color? Why not use other colors so that even colourblind people can drive. by [deleted]

This tradition screwed heavily with me when I started working on industrial electrical equipment. Green means safe (off) and red means danger (energized). More common in Europe, but since the main mfg of equipment I was familiar with was an international company, we had to be well familiar with both options.

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Toes14 t1_iy46fov wrote

That correlates to stoplights, since green means it's SAFE to go and read means STOP, due to DANGER of an accident.

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dimonium_anonimo t1_iy47fnv wrote

But pray, tell, what button do I press to make my machine go? Red, or green?

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nathan7356 t1_iy77h8a wrote

Green, for "all good, lets go!"

At least it should be, since e-stops are usually red for "crap, stop!"

There certainly are double-meanings here, depending on one's perspective and what one defines as "good" and what is "evil". Depends on if you're the operator or the mechanic, I suppose.

I see below that your machine seems to be the opposite. Most machinery I've seen has a green "start" button and a red "stop" button. I guess they're not as standardized as traffic lights. The hard part is when you press the green button, which illuminates the red warning light, lol.

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ashank3 t1_iy4eylk wrote

Wait, this sounds like it’s still consistent with stoplights. Green means safe/off and you can interact with said machine (equally for cars, you can interact and drive through) whereas red means danger/energized (for cars, you should not interact with driving and stop the car). For me, this sounds like it checks out! 👍

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dimonium_anonimo t1_iy4gp08 wrote

The counterintuitive part is that you normally think about things from the perspective of your car. Your car goes on green and stops on red. My machine goes when I flip the switch to red and stops when I flip the switch to green. If you think about someone else's car at the stoplight, then fine, this matches well, but I also think you're weird if you do that.

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