Sometimes you find a rolled-up bit of tinfoil acting as a fuse, but some previous tech put some FINESSE into doing the Wrong Thing

@AskChip @ifixcoinops My old EE professor would have loved this.

He had some hair-raising stories from his time working in power plants that he used to inoculate us against doing severely stupid things.

@ifixcoinops @tsturm Once upon a time I was called upon to change a blown 300 amp fuse at a McDonald's store. I did computer work there but I was ok with electricity. I turned the circuit off, the switch always makes a really loud bang when you do, gotta love to positive action switches. What I did not know, is that in spite of the noise, it was not working. I grabbed the fuse with large channellocks, they touched somewhere and vaporized a 1/4 inch chunk of metal and blinded me. Freaked everyone out but me.

@ifixcoinops @tsturm None of us could see for a minute but I was the only one who knew I was actually not dead.

@tsturm @ifixcoinops One of those bags of frozen fries would last me six months if I ate them every day, which I probably could if they still used the original fat. When they switched from the lard mix to an all vegetable mix, it actually increased the number of calories because the fries soak up more fat. But at least it's not saturated fat.

@tsturm @ifixcoinops I worked for a decent independent franchise. Many of the stores he bought and rehabilitated had the opinion that it wasn't old until it's sold.

@tsturm @ifixcoinops Climbing through the ceilings there was not fun, everything (and I do mean EVERYTHING) inside those ceilings is coated in thick layers of grease. I should say alternating layers of grease and pesticide, never saw anything living up there.

@tsturm @ifixcoinops I used to fix toasters and mini clamshell grills. The latter is a device to make quarter pounders in less than half the normal time by covering the burger top and bottom. Disgusting device. They had a tray to set it in to soak and clean it. They would plug the drain that kept the water level under the seal. Then it would vacuum up water as it cooled. next use, it boiled the water pushing greasy steam up through the cord into the fancy control box thereby damaging everything in between.

@AskChip @tsturm I'd like to type an appropriately-lengthy reply to this but all I've got is a quiet, ashen-faced "Good god."

@ifixcoinops @tsturm By the time I could get people to understand the why certain things get done, job turnover would hit and there would be someone new.

@ifixcoinops @tsturm All the timers use really expensive hall effect switches that even though they were soaked in grease, never malfunctioned. The push buttons slid a magnet over the hall effect sensor.
The English muffin toaster had a control board that adjusted time by platen temperature and used the most complicated zero crossing detector I have ever seen. That thing was many times more complex than it needed to be.

@ifixcoinops @tsturm Now the Vulcan Hart french fryer was ridiculous. The control board sensed flame by an electrode in the pilot flame using a process called flame rectification. 3 microamps would pass through the flame and trigger a sensitive gate scr to let it start the gas. The only thing keeping it working properly is that it had at least an eighth inch of conformal coating over the whole board. Most times it was coated with gunk so thickly I couldn't see the board or parts at all.

@ifixcoinops @tsturm I learned a massive amount about many different methods used to maintain electronic functions no matter what the environment threw at you.

I also learned that Courier corporation (who made a really nice 8080 based cash register system) had an engineer who was a malicious asshole. He had the main power connections coated with silicone RTV. Copper-solder-plug. Guaranteed intermittent failures in less than 5 years. I didn't find this out till we scrapped them.

@AskChip @tsturm Often looking at highly-specialized tech shows us more about what NOT to do. :) (although hall-effect sensors in the buttons are pretty cool)

@tsturm @ifixcoinops I did get all the McDonald's food I wanted, and I could make it myself if I wanted. And I got to hang with the managers on MLK day at the bar halfway between all the stores.
Actually, the owner was a pretty decent character. He used to buy lunch for us at the restaurant in town including the beer. Alas, he didn't quite make a turn on a road in his Porsche and died.

@ifixcoinops @tsturm Let's see, they have several banks of fuses or circuit breakers that each feed several breaker boxes for the electric toasters, at least 6 toasters at around 2 or 3 kw each. Then there are the holding bins, the Rooftop AC units, the grease catch vent units etc. This eventually got rewired to a single gigantic circuit breaker that fed the separate breaker boxes. But previously, as they expanded, they added on more capacity side by side.
Oh yeah, those walk in freezers are a joke to order

@ifixcoinops @tsturm Walk in freezers come as 4 by 8 insulation panels that lock together on all six sides. With a lot of luck, they will send you a set where they all fit together in the correct way. The one I helped install came with extra walls that didn't fit where they should to build a complete unit.

@ifixcoinops @AskChip My university time is 30 years ago. By now all his stories have spread in my consciousness into a thin film of wariness around electricity.

I do remember one where one of his coworker was trying to throw open a high voltage gate by hand and it arced, throwing the person 30 feet across the room.

He was a great teacher. We did a lot of ad-hoc back-of-the-envelope calculations based on whatever crossed his mind that day. 😅

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