Wiring a pair of 15 amp vacuum motors.

I like that......."sparky".
Much better than "crispy".

EE motto: Don't be a crispy.

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They make medium voltage extension cords, and one application where they are used is where they drag it along behind huge mining equipment.
Its a rather rugged cord.
Best not to touch it while in use.

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When I worked for TVA the overburden dragline at Paradise had crawlers pads two feet thick. The extension cord was about 3 feet in diameter and was a job to climb over.

Went to a pump station in 1978 in Nigeria bush and a guy comes out of the newly constructed control building. "well I smoked the PLC thing". Early Honeywell PLC 24VDC and in the dark he read it as 240v so he hooked it up. Manual was unopened. Didn't blow the power supply because it was external from the UPS.

Don't let the smoke out.

 

We have veered a bit "off-thread" I guess.
I read an IEEE paper about DC transmission lines, such as the 500 and 750 KV ones to distribute power across the US from east to west.
The biggest problem they had with reliability is that the farmers would dynamite the towers out of fear that the EMF was damaging their cows.

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Off topic? I thought this was the funny EE stories. We had a landowner kill himself while I was at TVA. He had buried a loop of wire under either a 230 kv or 500 kv transmission line and had stolen power for a few years. He killed himself while making a similar hookup for a neighbor. The only way we could figure he could have done it safely was if he had switches a each end of each loop of wire to he could lay it and terminate it then engage the switches. It was in a cultivated field so monitoring didn't pick up the ROW intrusion.

 

We had a survey crew come back one time and the guy said they were surveying under a transmission line, and his fiberglass pole began to glow.
And one guy parked his truck under it, and something happened to the truck, I forget what; induction maybe and it was shocking him.

That is wild about the loop.
Who would have thought?

I have not gone to a transmission line with a fluorescent bulb with copper wire wrapped around it, but I have heard tales.
I don't go near transmission lines unless I really have to.
You don't want to be around them if an insulator starts going bad.

There was an article about a transmission line that went over a mountain, to feed a factory.
The transmission line kept getting struck by lightning, and blowing out everything.
The soil was rocky.
The solution was to install like 10 ground rods on each leg of the highest transmission tower, with each ground rod 200 feet long.
No more lightning problems.

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The loop has to be offcenter to pick up just one phase, or at least his was. I don't really know if that's necessary. I'd love to build one with switches but I'm just not a thief but it would be fun.

TVA had inspection cars which grip the conductor and drives along. Live high voltage. Stop at an insulator and let go with one of three or four arms, grab the other side, inch forward, jump an arm around, etc. then you're on the next span. Right through mountains and inaccessible territory. The conductors will hold a lot of ice, of course, so a few thousand pounds of traveler is nothing. I was offered a ride, maybe later. I doubt they use that technology any more, but I wasn't dying to try it.

 

You can plant one end of a flourescent tube in the ground below a HV line and it will light up. Spillers mills had HV direct to a lot of the machinery, there was a distance exclusion zone around the conductors that ran through the plant to prevent you becoming a convenient earth passing by. Discharging lines is another missed factor, those buggers act like damn great capacitors (ground effect) and will kill you even when disconnected.

 

Yep, you have to be on your toes to be around MV.
Its a different world than the low voltage stuff.

My boss and the owner of the company I worked for was a pretty nice guy as bosses/owners go, but he got up in age and began to get senile.
We designed a lot of 1,000,000 sq.ft. industrial plants, and they had a lot of MV power distribution.
At one plant, they blew a fuse in one of the MV switches (he used S&C fused switches for most of his work; I use MV breakers).
Since it was a new installation and they did not have any spare fuses, he told them to jumper the blown fuse.
He assumed the fuse blew due to a surge when the power turned on.
They jumpered one of the fuses, and the next one blew.
He told them to jumper all the fuses, and they did.
When they closed the switch, the 8 ft. tall rectangular switchgear enclosure turned into a round sphere, but nobody was hurt luckily.
There was a fault in the cable downstream.

It was a dumbass thing to do for sure, and a good example of why it may be better to quit working as an engineer while you are ahead, and while your brain still works logically.
He got so bad that eventually almost all the engineers quit and either started their own business or went to work for someone else.
He had so much money that he did not care at that point, and he died a very rich (but no longer respected) man.

Edit:
He had a private plane that we used to fly to the new plants, it was a twin beech.
One day I was flying along with his son, and there had been a story in the paper a week earlier about a pilot/engineer flying a plane out west, and he had a heart attack and died.
His passenger was a fellow engineer, and he had to flight experience, but was luckily able to get the plane down on the ground again at night after a lot of trial approaches.

So I asked the guy "can I fly this plane?".
He said "Sure" and flipped the single yoke over to my side.
It was a low-winged affair, and extremely neutral, so if you leaned it over, it stayed over.
It felt like driving a car, but with the steering wheel coming off the column, but still connected by a rubber band.
I was able to fly the plane, but not without a lot of meandering, and would probably not have been able to land it.
It was very unforgiving, and rather quick when it did things.
Pretty much the polar opposite of the Aeronca Champ that I flew, where if you got into trouble, you could just let go of the stick and it would right/level itself.
I did not have any flight training, but I could fly a plane to some extent.
The main thing is to pull back on the stick when you turn, and don't get into a spin.
Avoiding stalls always seemed obvious to me; don't pull back hard on the stick/yoke.
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