Author Topic: Just electrocuted myself  (Read 21427 times)

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Offline nukieTopic starter

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Just electrocuted myself
« on: December 03, 2015, 09:06:57 am »
I was trying to dissect a 12v wall adapter, assumed that bleed resistor has done its job. Removed the board from the butchered plastic welded casing and instantly zap myself. It was quite painful and shocking from a pair of little 10uF 400v mains cap.

Unfortunately the circuit wasn't exposed so I didn't discharge the caps. Next time I'll wear gloves and definitely not look down on little caps!! Repaired many LCD and smps and yet still get zap. Please be safe when making repairs or dissection.
 

Offline amyk

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Re: Just electrocuted myself
« Reply #1 on: December 03, 2015, 09:12:14 am »
You weren't electrocuted, unless your ghost made that post. :P
 

Offline nukieTopic starter

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Re: Just electrocuted myself
« Reply #2 on: December 03, 2015, 09:16:49 am »
Near death experience :D
 

Offline Mechatrommer

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Re: Just electrocuted myself
« Reply #3 on: December 03, 2015, 09:25:55 am »
not exactly out of body but certainly lucid...

from a pair of little 10uF 400v mains cap.
oh that! 10uF is nothing compared to ceiling fan condenser cap. and ceiling fan condenser cap is nothing compared to The Real Mains.
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock
 

Offline lukaq

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Re: Just electrocuted myself
« Reply #4 on: December 03, 2015, 10:15:49 am »
I don't know, which one I hate more, DC or AC... I guess the one, where I had the least resistance/capacitance against at that moment, they both suck  :--

Offline Shock

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Re: Just electrocuted myself
« Reply #5 on: December 03, 2015, 10:49:41 am »
You weren't electrocuted, unless your ghost made that post. :P

He was electrocuted it can be used to describe fatal and non fatal injuries. Perhaps you are thinking of electrocution.
« Last Edit: December 03, 2015, 10:51:43 am by Shock »
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Offline Ian.M

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Re: Just electrocuted myself
« Reply #6 on: December 03, 2015, 10:58:50 am »
Less than a 0.6 joule shock, with a peak current of tens of mA, probably entirely within your  hand.  The biggest risk would be physical trauma if your hand hit anything jerking away.

Small SMPSUs usually don't even have a bleed resistor.   What they do have is a startup resistor that supplies the initial startup current to the controller toll the feedback winding takes over.   As the startup resistors are often badly under-specified, they commonly fail open circuit ==> any failed SMPSU that doesn't have a blackened fuse or other signs of catastrophic failure is highly likely to have fully charged reservoir caps.

OTOH older SMPSUs that could be switched (or were auto-switching) between 110-120V and 220-240V, commonly had two 200V capacitors in series when in 240V mode, and they did have resistors shunting them that acted as bleeders, but were actually for balancing the cap voltages.

I don't know, which one I hate more, DC or AC... I guess the one, where I had the least resistance/capacitance against at that moment, they both suck  :--

Don't work with high energy RF then.  Just about any random length of metal that's isolated or only has a single point ground can become 'hot' due to resonant coupling to the local EM field, and RF burns are particularly nasty and frequently cause deep tissue damage.
 

Online coppice

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Re: Just electrocuted myself
« Reply #7 on: December 03, 2015, 11:07:03 am »
You weren't electrocuted, unless your ghost made that post. :P

He was electrocuted it can be used to describe fatal and non fatal injuries. Perhaps you are thinking of electrocution.
Electrocution is the act of killing through electricity. Electrocuted is the past tense of that. When a criminal is electrocuted they don't just make them tingle a bit. Its kinda permanent.
 

Offline Towger

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Re: Just electrocuted myself
« Reply #8 on: December 03, 2015, 11:16:54 am »
Welcome to the world of the living dead.
 

Offline Psi

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Re: Just electrocuted myself
« Reply #9 on: December 03, 2015, 11:16:57 am »
yep
electrocuted = medically dead due to electric shock

eg
"John received an electric shock and was electrocuted"
"Sam also received an electric shock but thankfully did not get electrocuted"

You can be electrocuted and live, but it requires a defibrillator to restart your heart.

« Last Edit: December 03, 2015, 11:22:31 am by Psi »
Greek letter 'Psi' (not Pounds per Square Inch)
 

Offline jeroen74

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Re: Just electrocuted myself
« Reply #10 on: December 03, 2015, 11:32:44 am »
Many years ago I accidentally touched a 330uF (flash) capacitor charged up to a couple of hundred volts; my whole arm was painful for a week.
 

Offline alexanderbrevig

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Re: Just electrocuted myself
« Reply #11 on: December 03, 2015, 11:32:53 am »
sorry to be off topic but a defibrillator does not start hearts, they try to reestablish the contraction rhythm. After a flatline you need the brain and the electrolytes on your side.

EDIT: Glad you survived the shock. It's scary when it happens  :--
 

Offline Srbel

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Re: Just electrocuted myself
« Reply #12 on: December 03, 2015, 11:41:54 am »
Happened to me 2 times. But not from a capacitor. Directly from the mains (220V).

One time, it was mains hot on my right hand and mains earth on my left hand. So it went through the hart. It was not a strong shock at all, and not really painful. It lasted about 1-2 seconds, until I realised what is happening and released the screwdriver. It felt exactly like a shock from those prank toys that zap you if you pull the chewing gum or similar. I suppose that it was because it was not hot and neutral, but hot and ground.

Second time, it was through my fingers on right hand. Thumb and the next figure. I was repairing small SPMS. This time, I was not able to release the grip, but was able to move the arm back until I dropped the SMPS.
 

Offline SL4P

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Re: Just electrocuted myself
« Reply #13 on: December 03, 2015, 12:11:45 pm »
One time, it was mains hot on my right hand and mains earth on my left hand. So it went through the hart. It was not a strong shock at all, and not really painful. It lasted about 1-2 seconds, until I realised what is happening and released the screwdriver.
1-2 seconds before you realised?!  Not painful?
I suspect you were dead before you touched the beans!
Don't ask a question if you aren't willing to listen to the answer.
 

Offline GNU_Ninja

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Re: Just electrocuted myself
« Reply #14 on: December 03, 2015, 12:19:26 pm »
Shit Happens  :(

Always assume everything in any electrical device or installation is trying to kill you  ;)
 

Offline flolic

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Re: Just electrocuted myself
« Reply #15 on: December 03, 2015, 12:49:18 pm »
When I work on any kind of high voltage SMPS (power supply, camera flash...) first thing that I always do is to check voltage and discharge caps if needed. I don't have to say that I learned that hard (painful) way  :D

When poking around mains powered device or machinery, left hand is always on my back  ;)
 

Offline Deathwish

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Re: Just electrocuted myself
« Reply #16 on: December 03, 2015, 01:37:26 pm »
Nil points, your still posting therefore alive.
Electrons are typically male, always looking for any hole to get into.
trying to strangle someone who talks out of their rectal cavity will fail, they can still breath.
God hates North Wales, he has put my home address on the blacklist of all couriers with instructions to divert all parcels.
 

Offline Delta

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Re: Just electrocuted myself
« Reply #17 on: December 03, 2015, 01:45:48 pm »
Whilst we're being nice and pedantic, a defibrillator doesn't start the heart, it actually stops it.  It's down to nature to get it going again.
 

Offline grumpydoc

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Re: Just electrocuted myself
« Reply #18 on: December 03, 2015, 02:13:07 pm »
Whilst we're being nice and pedantic, a defibrillator doesn't start the heart, it actually stops it.  It's down to nature to get it going again.
Closer - stuns would be a better word.

Fibrillation is lots of uncoordinated electrical activity in the heart - each little muscle unit doing its own thing - however that does not pump blood, so you might say that the heart is already "stopped".

The defibrillator depolarises the whole heart at the same time so (hopefully) everything recovers in sync and the normal, co-ordinated, electrical (and mechanical) activity of the heart can restart.

You cannot defibrillate a "flatline" heart by the way - one thing which frequently annoys me about TV/Movie depictions of resuscitation attempts.
 

Offline Mechatrommer

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Re: Just electrocuted myself
« Reply #19 on: December 03, 2015, 02:30:51 pm »
Many years ago I accidentally touched a 330uF (flash) capacitor charged up to a couple of hundred volts; my whole arm was painful for a week.
when human muscle havent made a tense contraction for a long period of time and suddenly subjected to a very tense contraction (whether an order from the brain or the mains), the muscle (by the order of the brain) will adapt and regrow what it has lost, thats the painfull effect for a week.

One time, it was mains hot on my right hand and mains earth on my left hand. So it went through the hart. It was not a strong shock at all, and not really painful. It lasted about 1-2 seconds, until I realised what is happening and released the screwdriver. It felt exactly like a shock from those prank toys that zap you if you pull the chewing gum or similar. I suppose that it was because it was not hot and neutral, but hot and ground.
please retry with wet hands direct to the exposed copper of the hot, not through a screwdriver, and make sure the gnd wire is really grounded before doing so. i should not be held responsible for making this instruction... i'm anticipating will be less reply in this thread.

Whilst we're being nice and pedantic, a defibrillator doesn't start the heart, it actually stops it.  It's down to nature nothing to get it going again.
uncorrected thanks to me..
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock
 

Online mikerj

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Re: Just electrocuted myself
« Reply #20 on: December 03, 2015, 02:42:09 pm »
How many people have been bitten by the anode on the back of an old colour TV CRT?  That hurts.
 

Offline Deathwish

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Re: Just electrocuted myself
« Reply #21 on: December 03, 2015, 02:52:46 pm »
How many people have been bitten by the anode on the back of an old colour TV CRT?  That hurts.

Once many centuries ago when the damned screwdriver I was using to Discharge it came unstuck from the croc clip conn'ed to ground ...NEVER again.
Electrons are typically male, always looking for any hole to get into.
trying to strangle someone who talks out of their rectal cavity will fail, they can still breath.
God hates North Wales, he has put my home address on the blacklist of all couriers with instructions to divert all parcels.
 

Offline cncjerry

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Re: Just electrocuted myself
« Reply #22 on: December 03, 2015, 04:24:29 pm »
ya thought you were an engineer and here you are only a conductor!
 

Offline vodka

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Re: Just electrocuted myself
« Reply #23 on: December 03, 2015, 07:31:29 pm »

My first electroshock was when i had 5 years and i touched a teardown hair dryer that my dad was fixed. Before touching it , i saw that the dryer was unplugged then i put it the finger inside   :-DD :-DD

The second  electroshock and the more strongest until the moment ,i was when i tried to fix a computer power supply ,but for a bad decision i killed the power supply . Then i turned off extension cord and i unplugged the wire of the power supply , when i went to catch for the transformer  :wtf: :wtf: i stayed hooked for 5 seconds until i achieved to unhooked.

And the last i too was tried to fix an other power supply (notebook), i was searched a possible burned component but the component were buried in silicone, i had unburied it .While i did it , sometimes the right hand tried to close unwittingly and i considered these symptoms as fatigue. Until i touched the right elbow versus the wall :wtf: :wtf: and great electroshock. The funniest was that the power supply gave me electroshock without noticing :-DD :-DD
 

Offline Shock

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Re: Just electrocuted myself
« Reply #24 on: December 04, 2015, 04:56:48 am »
"electrocuted" is a contemporary word, just like it used to mean death by electric chair then death by electric shock, it now can mean either a fatal or non fatal shock, look up a few dictionaries for evidence of this.

Sentences like this "Joe was electrically shocked" are just as ambiguous so you need context and context is clear when you say you were just electrocuted (it was bad and you're obviously still here).

This quote from stack exchange sums it up the best:
"While the term electrocute was originally coined in 1889¹ to mean execution by electric shock, its meaning has evolved over time: first to also include accidental death by electric shock and later to include electrical injury,² generally serious in nature. So your use of the word does not fit the 19?? century coined meaning, but is perfectly in line with the broader meaning of the word as it is understood today."
Soldering/Rework: Pace ADS200, Pace MBT350
Multimeters: Fluke 189, 87V, 117, 112   >>> WANTED STUFF <<<
Oszilloskopen: Lecroy 9314, Phillips PM3065, Tektronix 2215a, 314
 


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