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Was working on a machine at work that has 220v 30amp three-phrase running into it. my screwdriver slipped and was about an inch from hitting a contact. I know that 220v 30 amp can kill ya but there is a few guys that have been hit with it in my job and just have to go to the ER but are fine. I figure if 220v single "could" kill is it a guarantee certain death with the 220v three phase?
 

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turn the power off first. here at the shipyard nearly everything is 440 3 phase and there have been people hit from it and walked away. i think it is mailny the amperag that kills you. amperage can throw your heart out of rythem. everytime some one here gets shocked, no matter how much voltage or amperag, they have to get a ekg done to check out everything
 

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Was working on a machine at work that has 220v 30amp three-phrase running into it. my screwdriver slipped and was about an inch from hitting a contact. I know that 220v 30 amp can kill ya but there is a few guys that have been hit with it in my job and just have to go to the ER but are fine. I figure if 220v single "could" kill is it a guarantee certain death with the 220v three phase?

Uhhh, steggy, .07 amps can kill you. Turn off the power first.
 

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OSHA requires that you have a lockout kit and use it. It is one of the more intelligent things they have ever required, since no one can be completely safe from those kinds of slippages.

Lock the power out and hold the key so no one else can turn it on.

Grainger Industrial Supply

This stuff is cheap, and can save lives. Get some, or if it's in the shop ( likely) USE IT.
 

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You may not even get shocked if the screwdriver has decent insulation, as 208 volts (I seriously doubt you have 220 three phase power) won't jump terribly far without inducement.

You may however be blinded by the evaporating screwdriver shaft as it will toss white hot shrapnel for several feet.

Don't ask how I know . . .
 

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Was your skin wet? If your skin was dry like it is here in the winter, you might have to put pressure on the terminals to feel the buzz.

Wait until you work with 480 volts. The voltage is high enough to boil tissues (make your fingertips pop off!) Each phase to ground is only 277 volts. Never known anyone that got hurt from it.

I worked with a few people who tried to test the primary side of the substations with their $450 NIST calibrated Fluke multimeter. 14,400 volts turned it into an instant burned piece of toast. Fluke honored their warranty and gave us a new one both times no questions asked! When you open up a large door with a big arm and see fuses with mufflers on them, you know there's serious high voltage in there. The mufflers on high voltage fuses keep the switchgear panels from blowing off when they blow.

I currently work with someone who dropped a wrench in a 2000KVA substation. All the energy went into vaporizing a tiny speck of the wrench into a huge metal plasma fireball of ultraviolet light and heat. He didn't get shocked, but looked like he had major sunburn over most of his body. He came back to work in the hospital gown since his clothes were blown off in the accident. One of the guys at work happens to be a professional photographer. I still have that picture somewhere...

I can tell you what its like to get hit by a 8uF capacitor at 15,000 volts from a cable tester. I heard a loud bang and lost my vision for a few minutes. I was still standing, but I would soon notice my arms were sore as hell. This cable tester would blow holes in cable or cause fluoresent lights to explode into dust, yet didn't burn me for some reason. I measured 8,000 volts left on the capacitor.
 

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I was working on a 440V 3 phase supply one time, managed to touch one of the terminals with my hand. :eek:

Gave me quite a belt, and I nearly fell off the drinks vending machine I was standing on at the time. Survived but my brain has never quite worked properly since.
 

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I once touched a nine volt battery to my tongue.

Actually, I used to fix microwave ovens, back when they were expensive enough to warrent fixing. It was so much fun when the bleeder resister to the cap went.
 

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My grand father was shocked with 440v/3 ph at the factory he owned. He had his tongue held with pliers so he wouldn't suffocate. Due to the injuries, he lost his left arm and became diabetic due to electrical shock. His belly and his right hand where also badly burned where the electrical bolts came out of his body.
He survived because the technician he was working with was trained in first aid for electrical shock.
 

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Yeah...for all the fun stories, there's an equal number of dead guy stories.

Don't mess with this stuff Stegen. You can die.
 

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Lock it out and ground it down to 0 volts.

You can be killed by very little voltage or amperage under the right(or really wrong) conditions. Of course many of people have lived through bolts of lightning. Hows your luck?

When working around electronics its always a good idea to use only one hand your less likely to shock the heart that way. But its better to just discharge the system.


Oh and never forget to unplug a dead machine when replacing the main fuse, opps all my training aside I still make mistakes.
 

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As has been discussed, there are far too many variables in real world situations to determine what "kills"...you can survive very high voltage contact, or kill yourself with a VOM if the situation is right...

In Steg's situation, whether it was a standard household outlet or 3 phase, was of no consequence. He would have contacted ~110 volts (not 220/221) and may or may not have been shocked depending on whether he was grounded, or otherwise completing the circuit...

Phase to neutral or phase to ground contact is far more common than phase to phase where higher voltages can be experienced... :twocents:

Btw Proto, if you contacted one leg of a 480 3ph, then you were exposed to ~277 volts...phase to phase would be around 400...it's a pretty dramatic difference, trust me... :crap:

Steg,
Think about getting some training or instruction, it's really fun and interesting, and could safe you some pain and suffering... :thumb:
 

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Btw Proto, if you contacted one leg of a 480 3ph, then you were exposed to ~277 volts...phase to phase would be around 400...it's a pretty dramatic difference, trust me... :crap:

Yeah, I know, I was trying to make it sound more dramatic :)

Though, you'd be amazed (or not) what 240 volts and high current can do to your thankfully insulated screwdriver when you try to fix your electric shower heater :eek:
 

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Though, you'd be amazed (or not) what 240 volts and high current can do to your thankfully insulated screwdriver when you try to fix your electric shower heater :eek:
Those damned things freak me out everytime I visit...standing in the shower with an electric appliance is just wierd to me... :googly:
 

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I had a 1/2 Farad cap at 12V in my car stereo system.

I was doing a quick swap on the amp and arced the screwdriver to the amp chassis. It welded the bolt onto the amp chassis and physically blew components off the PCB inside. The repairman said it looked like I'd tossed the amp out of a moving vehicle inside. Thankfully the screwdriver was isolated enough that I didn't also become a current path.

Prices have come way down on caps, and you can walk into a Circuit City and buy a 2 or 3 Farad cap...kids buy these things and put them into their systems without realizing the power therein all the time...

Most people don't know an unplugged CRT TV can kill you too.

Not stuff to mess with...
 

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I saw a guy get smacked with a guitar amp the other day...it sounded like a fist punching a side of beef...we laughed so friggin' hard that we all got kicked outta the store... :rotfl:
 
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