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View Full Version : Electric Shocks? whos had one, why, and how will you avoid



mrpackethead
01-18-2008, 03:48 PM
Whos been 'shocked' while working on their lights.. And why did it happen, and what are you going to do to avoid it again? Heres an opportunity to fess up, tell your story....

blurp
01-18-2008, 07:17 PM
OK, I'll own up to it. I was sitting on the ground in front of my house wearing a pair of cut-off jeans. I was investigating a 200ct strand with a section not working. (I think these particular strands use 6V bulbs in 20 bulb sections)

All of the sudden, something grabbed my leg and wouldn't let go. It was shocking me so bad I couldn't think clearly to find where the shock was actually coming from.

My wife finally unplugged the strand after I started yelling and flailing around. It turns out that a bulb was broken and both the wires iside the bulb stuck deep in my leg. That was why it was such a bad shock. I guess that they just barely penetrated the skin at first, but when I started flailing, I drove them all the way in.

Moral of the story: keep large areas of exposed skin away from the strands you are troubleshooting. :shock:

Trepidati0n
01-18-2008, 07:35 PM
I've been nailed by some pretty nasty stuff. The worst so far has been 270 Vdc. I'm pretty paranoid, however, sometimes things don't work as designed (i.e. a piece of test equipment says it is off but really isn't).

My recommendation is to get yourself a voltage sensing wand. All these wands do is look for an electric field and light when they get near one. These days I move the wand over anything that might be above 48 V and check it.

daviddth
01-19-2008, 12:19 AM
As an apprentice I managed to get 415V 3 phase across the back of my hand thanks to my boss at the time. I had isolated a large industrial water heater, tested to ensure it was dead, and then proceeded to remove the cables. When all 3 cables were pushed aside I had to reach in to undo a holding down bolt.

Being an old installation, the 240V light in the area actually came off one of the 3 phases of the water heater, so to help the boss unlocked the lock on the isolator and turned on the power so the light would come on.

Because the isolator was on the wall behind me I did not see what he was doing until he turned the switch on, the light came on. My hand, the back of which was neatly resting across all 3 phases of the cable felt like it was hit by a runaway freight train.

It took 8 weeks for the 3 broken fingers to heal, and about the same time for the burns to fade. The hand ached for 6 months.

Been hit with 240V a few times but nothing was ever as bad as that 415V hit.

Trip
01-19-2008, 12:32 AM
When working in the switchyard at one of the plants, one of our static grounds on the 500kVAC breaker we were working broke loose and brushed me, that knocked the ! out of me. Probably somewhere in the 1000s, but with no amperage behind it.

Been hit with 250VDC a lot, that always stings like a mofo. Not as bad as the static wire though.

I've hothanded 161kV. It's an interesting feeling to reach out and grab that safely.

daviddth
01-19-2008, 12:49 AM
I saw the jib of a crane hit a live 500KV line - I got showered with the sparks as I was in a cherrypicker about 10 meters below. Didnt feel a hit, but the earth cable on the crane was reduced to small stumps at each end, and the rest vaporised.

Any DC hit above about 110V hurts. We have 240V batteries here and a few guys have had hits when theres been an earth fault and they say it really does sting.

shocker
01-19-2008, 02:21 AM
well i work in construction as a electrician and i have a great respect for electricity, i had my share of shock voltage ranging from 24vac to 600vac but always manage to get lucky and was walking away without to much damage i dont wich shock to anyone it hurt like hell u can feel the sinwave passing throu you and it is not a good feeling. it is my job but i always try to work as far as i can from live wire

omzig
01-19-2008, 05:33 AM
A few years ago, the GFI kept tripping on the outlet that I had most of my lights plugged into. I determined that it was a faulty GFI receptacle and not an actual ground fault. I'm going to replace the receptacle, so I shut off the breaker and then stuck a tester in the old receptacle and sure enough, no juice. I removed the screws and then, as I was pulling the receptacle out, I got a pretty good jolt :shock: and a minor burn on my fingertip. It turns out that I shut off the wrong breaker and when I used the tester I didn't realize that the GFI was tripped.

Watch out for those power lines or you may end up like this poor guy:
http://video.aol.com/video-detail/man-electrocuted-while-hanging-christmas-lights/1653241771

daviddth
01-19-2008, 07:30 AM
Watch out for those power lines or you may end up like this poor guy:

Outch, 12KV. I'm lucky as this area was upgraded to ABC cable about 4 years ago. ABC is 415V (or 11KV) 3 phase insulated cable in a twisted bundle. The connections are insulated, so our street has no "bare wires" so to speak.

Alas it's also a target for idiots to throw their shoes over the line, so that happens a lot too.

Deast
01-19-2008, 08:30 AM
I was working on a 220v treadmill about 10 years ago. I was making an adjustment to the lift system, trying to level it out. I had hit the capicator for the ac lift motor, and got a hit from my hand and out the side of my leg. It didn't hurt that bad, and was rather quick. The funny part was I had a hole in both my hand and leg about 3mm wide. When the skin started to grow back, it grew back in little spikes in the hole.

Jeff Millard
01-19-2008, 09:25 AM
OK, I work for the power company in New Jersey. Quite a bit of the equipment was in place providing electric power to customers before there was electric distribution anywhere else in the world. It's old, outdated, brittle and delicate stuff that falls apart if you touch it. SOOOO we try not to touch it... but.... it sometimes breaks and needs some attention. Every time I work on it, I test my ability to conduct electricity through my body...

It's just a by-product of my employment.

Jeff

tonypgst
01-19-2008, 09:49 PM
Working as an Electronics Technician in the Navy, I've felt my share of jolts and tingles, nothing major really. However, the worst was not a by product of work or troubleshooting. About 6 years ago, I was working in the garage at our new house in a fairly new subdivision. Our house was on a lake, and as new subdivisions go; our house was taller than any tree in the area. A storm was rolling through so I decided to go and shutdown and disconnect the computer as I had not yet hooked up my UPS for surge isolation. The last thing I remember was grabbing the mouse. I came to about 6 feet from where I was standing near the computer facing the opposite direction and on my stomach. The house smelled strongly of burnt cabling and components. I used the cell phone to call the fire department. Once they arrived, they didn't really believe I had been struck by lightening. A quick trip into the attic revealed the 8" diameter hole in the roof directly above where my computer desk was. The burn marks in the roof trusts showed the ligthening’s path to the A/C ducting and cable, phone, and electrical wiring. Anything plugged into an outlet of any type was dead. The electricians making repairs found that nearly every ground connection in our service panel was loose. Insurance came through and we fully recovered after about 2 months of work and shopping for replacement items. The right side of my body was sore for a few days and my neck muscles gave me problems for months. Fire department was nice enough, but you know, they never did check me out. I guess they saw me walking around and figured I was ok. To this day, I don't know how long I was out.

The weirdest thing of all looking back is that I knew it was going to happen. It is so strange to have all the hair on your body stand up and you just know something is not right. I never heard anything, but do remember what I would call just a quick flash of light. Next thing I can recall is that I was coming to and my ears were ringing.

skygodtj
01-20-2008, 10:02 PM
Wow, struck and lived?? You are very lucky! ..makes my being hit by a TV's B+ anode(abt 30K) pale in comparison! Only way I was able to let go was I fell over..

TJ

DJzrule
01-22-2008, 11:37 PM
I was walking around Fortunoff's (department store) one day and went by the prelit Christmas trees. There were LED ornaments that were on it and I picked one up to get a closer look at it and there was a couple of loose connections going to the last LED in it's chain. Gave me a nice buzz and I couldn't feel my arm for a few seconds. Made it shake a bit too. Stupid 110v. I also have had some smaller shocks from speaker amp capacitors and stuff. I usually blow more stuff up then get shocked (crossed a couple wires in a junction box twice and sparks went flying, literally. My bad, never happened again).

pixeldigger
01-25-2008, 10:51 AM
I licked a 9V battery once.


I've had my tools arc from touching the wrong places, but fortunately, I've never really been Zapped.
My plan is to keep it that way.

Ronp
01-26-2008, 10:13 AM
Disasembling disposible cameras got me a few times last year.
they have a good bite exspecialy when you dont exspect it .

Photovor
01-30-2008, 05:53 PM
My hacked together version of yard lights got me once, but nothing more than a little tingle (very low amperage). I've also had the privvy to get hit with 480vac while working on live overhead high-bay fixtures. (Could not turn the circuits off because of the working industrial environment). Wasn't a smart move, and a complete lack of gloves aided in the judgement call.


GFCI protection (NOT SURGE PROTECTION) is what I'd recommend on any of your outdoor circuits, and the NEC and/or local city codes REQUIRE these. Even thought xmas displays are pretty much temporary, they still need to have some kind of protection. Don't want sled riding kids to short out a display and get a shock.