[rrolleston]

Ok talking about magic smoke lately. What was your best or should we say worst. Mine was having a bad day miswired a generator and took out a fan in a fridge intercom system and a small stereo system. It could have been much worse. So I try to be more careful and I am hoping that was my last time.

 

[480sparky]

Second-year apprentice: Was told by foreman to push a fishtape down a 3" pipe from a gutter.... it comes up 'right over there', 30 feet on the other side of the mechanical room. So I get a fishtape and start pushing.

And pushing.










And pushing.

























Aaaaaaaaaaaaaaaaand pushing.







































About the time I realize that I'm probably more than 40 or 50 feet in........ BOOM! The pipe and fishtape shakes, and the lights flicker off.

Turns out, I was pushing the fishtape out to the building transformer and shorted out across the terminals. Dropped out every single computer in the building (state gubbamint office!). And this was back before UPSs.

 

[Jlarson]

I hooked up somebodies ghetto ass idea of a homemade UPS and it turns out they had the power inverter and main power terminals crossed. Customer didn't want us to go through the control panel and check everything out first, time = $$$$.

Every solder joint on the inverter board blew out and then the board started on fire. :laughing:

 

[bobelectric]

Wiring an office building when I was a kid and didn't know or the boss knew they wired in a high leg delta service, not a wye. Ballasts were screaming.

 

[8V71]

Mine was having a bad day miswired a generator and took out a fan in a fridge intercom system and a small stereo system.

Why do they need a fan on a fridge intercom system. On second thought, why is there an intercom system inside of a fridge. Safety thing? :jester:

 

[bobelectric]

I don't like when


















































Dudes du dis.

 

[alambre]

Checking board on cnc turret press, meter lead kind of slipped. Fried a couple of other boards. First tech we called could not fix, he called another tech..tech from fanuc fixed it

 

[brian john]

600 KW motor generator the bypass for the MG was a momentary passive closed transition with utility. We had gone through all the controls, performed a couple dry runs with MG disconnected, timed everything. Went for the smoke test and one relay stuck closed. Needless to say the utility has more muscle in this fight and the rear end of the MG smoked.

 

[Big John]

I will graciously offer up a screwup by someone else:

Trouble call at a plant with a 500HP DC motor that blew up when they closed the breaker and filled the plant with smoke. Really old design a bunch of manual safety-overrides and field controls; you really had to know what you were doing to put the thing online.

Well, I show up and ask the operator to walk me through what he'd been doing when this happened, so he goes "All I did was this!" and before I could say a word he closed the damn breaker again.

*BOOM* and the plant fills with smoke.

:wallbash:

 

[erics37]

I have one that I was involved with but wasn't my fault by any stretch.

Mounted a couple of drives in an upstairs electrical room at the crab plant. Well when they started up their huge crab cooker, the woefully inadequate HVAC system did not vent the steam like it should have, and the entire upper floor filled up with fog. Almost zero visibility. Anyway it filled up the electrical room too and burned up all the drives.

I got a call at 3 in the morning on that one, had to go and temporary everything up on across-the-line starters. They modified their exhaust system and things seem to work after that :laughing:

 

[Bkessler]

A guy I worked with once got a gray 277 neutral mixed up with a black 120 line, told my boss he tested everything when he didn't. The result was 8 smoked computers.

 

[RHWilks]

I was in a panel room about 8 years ago in a jcrew store making up a j box in almost dark, I miss landed a noodle on a hot wire, 28 par 30 died that day loudly....pop pop pop... I don't guess 208 is a option for halgen par bulbs lol.

 

[just the cowboy]

Boom poof bam

I had just taught a class on basic troubleshooting to the mechanics in a bread plant, and told them sooner or later you will blow something electical up. When you do you are going to say ah sh**, then you will look around to see if anyone saw it, then fix it. Two weeks later I was working on a panel tracing wires and a ground wire fell out of the Panduit ( just tucked in) and shorted across the 200amp main all three phases . The mechanics came up and asked if I said it and looked around, yes I did.

Saw one on a CNC machine once a metal chip flew off the machine and into the control cabinet (200 pc cards) across 120v to the 5vdc power supply, Boom poof bam are not words to describe it, Looked like lost in space (if you remember that part).

 

[CopperSlave]

Six of us were in this chick's van heading to see The Greatful Dead and....wait...wrong magic smoke story.

Hooked up a couple of 480V shoe-box fixtures and didn't change the factory multi-tap....which was 240V.

 

[CyberKnight]

At our plant we had a big mg set to run DC drive 25hp wire drawing machines . Old magnetic contact controllers. We relocated the machines and got a big dc rectifier instead of the noisey mg set. Got it all hooked up and for a test and we ran a machine. Started fine and ran good upto speed. Hit stop and all the smoke came out of the rectifier with lots of flashing. Called the company that made it and ended up putting a large regen bank of resistors on it .for when the machines come to a stop. The mg set would absorb it but the new stuff just went poof and bang. Will never forget that one. We are 90% solid state drives now, much nicer.

 

[Service Call]

Wired a boost transformer up wrong. Whiz bang all done. Thought it was bad. Got a new one. Did it again. Come to find out I was using the wrong wiring diagram. Son of a b***h.

 

[nrp3]

Turned on a 150w hps fixture the other day full of water. It was going to get replaced anyway. Nice smoke show with that one.

 

[Rollie73]

I found out (the hard way) that the 120 volt ballasts exit lights don't like 347 volts. They were very bright for a very short time.


Had another mishap with 347 volts when an apparently color blind apprentice who worked with us mistook the red 4" square box for an orange 4" square box and tied in a 347 volt cable to a fire alarm bell circuit box.
I was terminating the fire alarm panel when another JM turned on the lighting circuit causing a few popping noises and all the magic smoke drifted out of my fire alarm panel. I'm sure the puzzled look on my face was pretty amusing for a few minutes.

 

[electro916]

When I was still in tech school, 120v ballast on 277v, lots of smoke and then set all the school fire alarms off, secretary got on the loudspeaker yelling "This is not a drill, evacuate evacuate", good times:laughing:

I once knocked the plug for the main server rack out of the receptacle in a busy hospital:whistling2:

Wired a 75kva 480v to 600v transformer, customer provided transformer, it came in damaged, I refused to hook up, customer demanded that I hook it up. I megged to ground, it checked fine, made the terminations, threw the breaker and BOOM, it was internally shorted.

 

[LARMGUY]

I was a real newbie. All I had been told was Red Black Green White, don't let the smoke out. Red and Black were DC power, Green White was communications line or signal cable. I was assigned to go to this big ammonia plant and replace a power supply board. The board was already removed by maintenance and all I had to do was replace the board and "plug it in". Well, I "plugged it in" to A/C not through the wall wart transformer. One mini lightshow later and the exhaust fan venting the blue smoke from the caps and traces on the board still smoldering, I sheepishly left the plant, tail between my legs.

I took classes and bought a lot of books after that.