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General => General Technical Chat => Topic started by: grifftech on December 15, 2015, 05:42:21 am

Title: shocking
Post by: grifftech on December 15, 2015, 05:42:21 am
What is the highest voltage shock you have gotten ? :-BROKE
Title: Re: shocking
Post by: jwm_ on December 15, 2015, 05:59:31 am
I imagine for most people it is the few kilovolt shock they get from a doorknob in cold weather.

Now, my scariest shock in recent memory was a 450V 480uF capacitor that somehow got thrown in a parts bin charged at some point in the past and sat there months or years waiting to bite me (I have no idea when it happened, but it was a pretty old bin that had gone through at least one move.). I have been shocked with wall ac before and it bites and you curse but this dc was different, full paralysis with the cap clutched tightly in my hand staring straight ahead, felt like a long time but was probably only a handful of seconds but felt like forever in retrospect.
Title: Re: shocking
Post by: Melt-O-Tronic on December 15, 2015, 06:09:58 am
~400VAC from my old Bell & Howell oscilloscope when I was 11 years old.  I did an alignment procedure from the manual which involved running a wire from the transformer to the input through a resistor.  I forgot to unplug it before dismantling the setup.  :palm:  My fingers involuntarily clamped down on that resistor lead (transformer side) like a Vise Grip.

It was a highly educational experience.   ;D  I was always much more careful when discharging the flyback anode from big color TV's!
Title: Re: shocking
Post by: Halcyon on December 15, 2015, 06:18:33 am
About 300VDC from a photoflash capacitor in a camera flash circuit. It didn't tickle.
Title: Re: shocking
Post by: Shock on December 15, 2015, 06:24:30 am
I think he is asking me.
Title: Re: shocking
Post by: matseng on December 15, 2015, 06:29:33 am
Except for trying to remove a physically broken 240 v bulb that was on a live circuit and holding the lamppost with the other hand (still got the scars on my fingers after 35 years) I once lightly touched a transmission conduit in a ground station for avionics navigation.  I got "nice" deep burns in the tissue on the top of my fingers, I've got no idea of the voltage used in a radio transmitter that puts out a few KWs...
Title: Re: shocking
Post by: matseng on December 15, 2015, 06:32:07 am
I think he is asking me.
Nah, lets ask https://en.wikipedia.org/wiki/William_Shockley (https://en.wikipedia.org/wiki/William_Shockley) - I wonder how many times he heard that joke :-)
Title: Re: shocking
Post by: tggzzz on December 15, 2015, 06:39:11 am
A few hundred thousand volts; don't know how many exactly. Great fun, everybody in the class had a go.

From our school's van def Graff generator, unsurprisingly.
Title: Re: shocking
Post by: timb on December 15, 2015, 06:40:04 am

About 300VDC from a photoflash capacitor in a camera flash circuit. It didn't tickle.

Same here. I was 11 and decided to take apart a broken Polaroid instant film camera while sitting on my bed one night, to see if I could fix it. I had it halfway apart and inserted an empty film cartridge to test it (the film packs also contained a battery).

Somehow I must have touched the flash cap leads and I guess I threw myself backwards trying to get it out of my hands, because I fell right out of my bed... Which happened to be the top of a bunk bed. The fall hurt more than the shock!
Title: Re: shocking
Post by: Brumby on December 15, 2015, 06:47:41 am
If we ignore the usual spark plug and static experiences - 716vac.

I achieved this in my very early days when I took 2 train transformers and wired the 12vac connections back to back - as a practical experiment in transformers.  I plugged the first one into the mains and expected to find something a bit under the 240v mark (due to lossess) on the mains plug of the second.  I wasn't careful enough in my setup and I managed to get a fleeting zap from one hand to the other.  I felt it through my chest and realised I had been extremely lucky.  Out of curiosity I measured it - very carefully - then immediately turned it off and dismantled it.  Never to be repeated again.
Title: Re: shocking
Post by: v8dave on December 15, 2015, 06:55:16 am
25KV from an old colour TV. Luckily I was following the correct safety procedures and using only 1 hand to probe the circuit and using an isolation transformer etc but I accidentally brushed up against the HT lead and it gave me a jolt. I got thrown against the bench behind me. Needless to say I have been ultra cautious with electricity ever since and the most I have had since then (30 years ago) is 220Vac just the once.I am so careful these days to avoid anything with mains voltages.
Title: Re: shocking
Post by: Halcyon on December 15, 2015, 06:56:13 am
Check out the OPs post history if you want to see something truly shocking, a spam bot contributes more meaningful content.

A bit harsh isn't it? Sometimes the simplest concept can evolve into all sorts of interesting conversation. It's like that word game where you start with a single word and everyone goes around adding a word to make a story. Plus it's Christmas... Mr. Cranky pants ;-)

I figure if you're not being malicious or bullshitting people, post away! If you also look at Grifftech's history, you'll probably soon work out that he is very young. Cut him some slack.
Title: Re: shocking
Post by: tautech on December 15, 2015, 07:13:53 am
40+ years ago (shit am I that old?) I made a universal HV mains PSU for the valve projects I fiddled with back then, SH transformer, rectifying valve, chassis and as many bits that I could scrounge from stuff lying around.
700VAC @ 100mA sent me across my bedroom and onto my back. Still had the homemade probe leads in my hands.   :-DMM
Must have done something to my brain as I've been hooked ever since. :-DD
Title: Re: shocking
Post by: Muttley Snickers on December 15, 2015, 07:29:44 am
I just went out to the letterbox to get the mail and was completely shocked by the amount on the electricity bill, so that now takes top honour just above the neighbours digital camera which whilst in the process of repairing it gave me a good whack, I put it down, had some lunch and then went to finish it off and it got me again.
Title: Re: shocking
Post by: Halcyon on December 15, 2015, 07:33:26 am
I just went out to the letterbox to get the mail and was completely shocked by the amount on the electricity bill, so that now takes top honour just above the neighbours digital camera which whilst in the process of repairing it gave me a good whack, I put it down, had some lunch and then went to finish it off and it got me again.

You could try https://www.makeitcheaper.com.au/ (https://www.makeitcheaper.com.au/)

I switched over to Energy Australia (from AGL) through this mob and I'm now saving 4.85 cents per KW on power and 0.53 cents per MJ on gas, plus I get $50 credit to my first bill. It doesn't sound like much but every bit helps. I should mention that this is before any discounts applied for paying on time and bundling services.
Title: Re: shocking
Post by: Muttley Snickers on December 15, 2015, 07:45:19 am
I'm already with them and have been since day dot, funny thing is that I rang them after the last shocker and they promised to give 30% off all future accounts for loyalty and paying before the due date, which we always do anyway.

I going to plant a lemon tree and go completely off grid, it's all about consumption as you well know.
Title: Re: shocking
Post by: G7PSK on December 15, 2015, 09:02:12 am
About 15 KV from a 22 inch early 1980's colour TV also had 10 to 12 KV off an electric fence line many times.
Title: Re: shocking
Post by: funkyant on December 15, 2015, 09:03:52 am
In the 90s, I was changing a female end of a 50m 3 phase cable on site at a concert - when somebody plugged the other end in. Yes I was young and stupid and there were so many safety fails that led to this happening.

Luckily I was crouching down on my feet when the screwdriver exploded. My legs decompressed and I flew across the floor. I was quite shocked  ::)
Title: Re: shocking
Post by: Galenbo on December 15, 2015, 09:24:45 am
What's the voltage on a spark plug of a running car? 10KV, 20KV ?
Title: Re: shocking
Post by: tggzzz on December 15, 2015, 11:21:52 am
... they promised to give 30% off all future accounts for loyalty and paying before the due date...

Lucky you. Over here in such circumstances the SOP in many consumer sectors is to add 30%, since many of their sheep won'r notice and can't be bothered to switch.
Title: Re: shocking
Post by: TerraHertz on December 15, 2015, 12:18:05 pm
What is the highest voltage shock you have gotten ? :-BROKE

Not sure, but the arc from the transformer I'd rigged in an oil bath would strike at about two inches, and draw out to maybe a foot. That was lots of fun. Until one day I dropped the insulated HV wire, and the end fell past my left index finger.

I was about 12 I think. Apparently it didn't kill me. Though sometimes I wonder. If it did kill me, that would explain a lot.
Title: Re: shocking
Post by: rsjsouza on December 15, 2015, 12:31:14 pm
What's the voltage on a spark plug of a running car? 10KV, 20KV ?
I think it depends on the car. I still have a VW bug coil from Bosch that gives me between 13 and 15kV in a regular day (not too dry, not too damp).
To the OP, there is a nice thread where zillions of folks reported their shock experiences:
https://www.eevblog.com/forum/chat/electric-shock-experiences-for-those-still-alive/ (https://www.eevblog.com/forum/chat/electric-shock-experiences-for-those-still-alive/)
Title: Re: shocking
Post by: tautech on December 15, 2015, 10:01:01 pm
What's the voltage on a spark plug of a running car? 10KV, 20KV ?
Typically modern ignitions can produce up to 25 KV.
High performance (racing, drag car etc) up to 40KV

Compression ratios, boost pressures and fuel type used will determine the voltage and/or the energy level required.
Title: Re: shocking
Post by: moya034 on December 15, 2015, 10:06:35 pm
The scariest shock I received occurred when I was welding on rail cars. I was on top of a car doing some air-carbon arc gouging, and I found when I went to strike an arc that the piece of metal I was resting my elbow on was NOT grounded to the car adequately. Of course, I was well grounded to the car myself because I was sitting on it and it was a hot, sweaty day. That shock threw me back about 2-3 feet... I'm lucky because if I had been facing the opposite direction I would have fallen off the car. (The place I worked was too shitty and cheap for proper fall protection)

(that was probably 90-150v open welding circuit voltage with the machine set on 350-400 amps)

edit: if you want another good rail car story, ask me about cutting torches sometime
Title: Re: shocking
Post by: HarlanKing on December 15, 2015, 11:15:52 pm
I've only ever had 120Vac shocks, never across the body and i plan on keeping it that way. Too much respect for electricity as an electrician!



Sent from my LG-D852 using Tapatalk

Title: Re: shocking
Post by: SeanB on December 16, 2015, 10:42:00 am
edit: if you want another good rail car story, ask me about cutting torches sometime

Did it involve a tank car that had as previous product either a flammable liquid or a powder.......

Did use a plasma cutter at work to reconfigure a stainless steel tank. 20 minutes to convert it from a 1kl tank to a series of stainless steel sheets for recycling. Might be doing that next year to another tank, though that one will be going to a new home most likely and will have to get welded back together afterwards. Going to be a fun day for the welder in putting it back together, especially as i need a chain block to move some parts.
Title: Re: shocking
Post by: moya034 on December 16, 2015, 12:05:50 pm
Did it involve a tank car that had as previous product either a flammable liquid or a powder.......

Fortunately, no. I was working on the top corner of a coal car. I have my hood down, am welding, everything is fine. Then after 30 seconds or so there was a loud boom and the car rocked back and forth. I put my hood up and everyone in the shop is staring at me. I look into the car and I see a teeny itty bitty flame coming from the coming cutting torch which was laying in the bottom of the car. It turns out I hadn't closed the valve all the way, and when enough built up in the car the welding spatter lit it up. (We used propylene fuel gas)
Title: Re: shocking
Post by: SeanB on December 16, 2015, 12:22:29 pm
Good thing there wan not enough coal dust, or you would have been unable to post that.

My dad had a story involving a Lister donkey engine, which was started with high pressure air. The guy used an oxygen cylinder instead of the nitrogen. The head left for a half mile journey, the crankshaft and piston made themselves a new deep hole in the ground and the shed was flat. The guy survived, though he was partly deaf afterwards.
Title: Re: shocking
Post by: G7PSK on December 16, 2015, 04:06:23 pm
I knew a man that ran a scrap yard,one day he got a job of removing some old fuel tanks from a rail yard. He decided to just put a gas torch through one of the legs the tanks stood on, he assumed the tanks were empty but found that the first one he dropped was about half full with around 5,000 gallons of gas oil (diesel) when the tank crashed to the ground and burst.
I knew some one else who brazes up an old car petrol tank, he took the precaution of washing it out with soapy water but there was enough petrol left in the seams and the rust inside the tank to boil out and then blow the side out of the tank.
Title: Re: shocking
Post by: DenzilPenberthy on December 17, 2015, 10:33:41 am
My dad had a story involving a Lister donkey engine, which was started with high pressure air. The guy used an oxygen cylinder instead of the nitrogen. The head left for a half mile journey, the crankshaft and piston made themselves a new deep hole in the ground and the shed was flat. The guy survived, though he was partly deaf afterwards.

A similar thing happened where a friend of mine used to work - Someone was pressure testing the inlet manifold of a diesel engine. The air compressor was broken that day so the boss says to use an oxygen cylinder instead. Several people say that's a bad idea but get the 'do as you're told' response. Pressure test gets done and manifold isn't leaking. Happy days. Some time later the mechanic starts the truck to move it, the engine takes a nice lungful of pure O2.  A very loud explosion and the cylinder head parts company with the rest of the engine and departs for a short flight across the workshop and the pistons and crankshaft exit rapidly through the sump onto the floor. Also there is another bloke in the workshop who was very seriously injured in an accident and had only recently returned to work - he was found cowering under a bench screaming and shaking, clearly having some kind of PTSD meltdown. None of the people in this story work there any more, all for the exact reasons you'd imagine!
Title: Re: shocking
Post by: VK3DRB on December 17, 2015, 11:17:44 am
About 300VDC from a photoflash capacitor in a camera flash circuit. It didn't tickle.

Unlikely. Almost everyone has had many thousands of volts from an electrostatic discharge.

The biggest electrical shock I have had was in excess of 100,000 volts from a Van de Graaff generator. It did me no harm :o
The most painful shock was around 22kV off a picture tube ultor I thouht I had discharged :palm:
Title: Re: shocking
Post by: bitslice on December 17, 2015, 11:34:43 am
1kV off an RF circuit I was fault finding on, it drilled a tiny hole through my finger.

And 240v AC for a few seconds, which psychologically is very unpleasant.
Title: Re: shocking
Post by: aon on December 17, 2015, 12:53:14 pm
I've had a few off electrical cattle fences, according to the manufacturer the voltage on those is 5 - 10 kV. Also some off ignition systems that are similar voltage-wise I guess?

Far from being as scary as getting shocked by mains, though.
Title: Re: shocking
Post by: Ysjoelfir on December 17, 2015, 01:06:11 pm
My first shocking experience was when I was around 12 years old. I disassembled an old AT PSU to change the Fan with a sparkling, blinking, LED thingy. But as I had that PSU lying at the bench I decided to give it a try wether the fan was actually needed. So I let it running for half an hour with no load, thinking that would heat it up, and touched the heatsink while that sucker was still plugged directly into mains, no safety transformer, no nothing. So... I touched the heatsink which was directly connected to the switching transistor and therefore at the main input cap, which was charged to around 325V DC. Next I remember was, that I was sitting on my bench, breathing heavily, hearing my heart beating the crap out of my stomache. Half an hour later i relaxed somehow and noticed the PSU was gone. looking around for it I found it laying behind me where i threw it because of the muscle cramp in my arm. At least it "only" made a little punctuation in the wall of my room. since then I avoid those damn heatsinks at all cost.

next shocking experience was at my education. 16kV from a television. Wanted to show my master that i found a little spark arking over at the anode and little idiot Ysjoelfir had nothing better in mind than pointing at it with an unisolated screwdriver. It bit me, I jumped up, throwing the TV set down. My master tried to catch it by grabbing the neck of the CRT. Wasn't a good idea as he found out seconds later as the tube broke and sucked his hand right into the broken glass. He got some really nice scars from that...
Title: Re: shocking
Post by: ilporcupine on December 27, 2015, 09:24:47 am
At age 11 or so,  Jacob's Ladder with neon Xformer, 20kv if I remembr correctly.  Arc went out, reached across bench to get adjuster(piece of plastic) and bumped against electrodes.  Bench was parallel to and couple meters from heating oil tank, which I ended up laying atop! Walked funny all day.... :palm:
Title: Re: shocking
Post by: Tinkerer on December 27, 2015, 09:47:48 pm
Dont know how many volts is an electric fence meant to keep horses. Didnt hurt despite knocking me on the ground.

Once had 120V AC going through my hand. That is, until I noticed something felt funny and removed it from bridging the two heat sinks in a power supply.
Title: Re: shocking
Post by: Psi on December 27, 2015, 09:50:48 pm
300kV Telsa coil
Title: Re: shocking
Post by: rrinker on December 28, 2015, 02:46:49 am
 Whatever the voltage used in a table top early 50's tube AM radio would be. I was given one, that had a broken tuning dial. I was tuning it with a screwdriver, careful to touch only the insulated handle. Unfortunately I was standing in bare feet on a plain cement floor, and my hand slipped down to the shank of the screwdriver. I was paralyzed - couldn't move my hand away, couldn't yell for help.  I saw people outside the windows on the patio but couldn't yell for help. It seemed like I was stuck there for an hour, more and more thinking I was never getting out of this unless someone randomly came down to check on me. Eventually my hand started shaking enough to dislodge the screwdriver and the current was broken and I was able to move again. It probably was a minute or less in real time, but it's like time slowed down.

 The STUPIDEST thing I ever did, I was maybe 5 or 6 and found an old flashbulb - the one time use kind, not an electronic flash. The flash on our old Polaroid used 2x AA batteries. I touched it across the terminals of a 9V battery. I pretty much figured I'd blinded myself, so I ran and hid for a few hours. I truly couldn't see anything, and no way could I go run for my Mom saying I'd blinded myself. After a few hours my vision did return and I never fessed up what I did. I also never did anything so stupid again.

Title: Re: shocking
Post by: Brumby on December 28, 2015, 01:05:54 pm
300kV Telsa coil

That would have tickled.
Title: Re: shocking
Post by: sarepairman2 on December 28, 2015, 04:26:45 pm
I shocked myself with a 11kV, ~20mA boiler ignition transformer.

I was playing with a neon bulb and the arc jumped over to my hand. Nearly knocked me on the fucking ground, I felt half my body convulse.


It was extremely unpleasant.  :phew: I think it used my finger as a jump point to the chassis (that was ontop of a ESD mat maybe). I am glad I always observe the one hand rule due to being cowardly  :-+
Title: Re: shocking
Post by: cvriv on December 28, 2015, 05:16:39 pm
Holy hell this thread scares me. I'm not going to read through all the stories. I have a question... might be a stupid question.... how many of your have been doing electronics for a VERY long time and have NEVER got shocked by an ass puckering amount of charge? If no one I hope to be the first :(
Title: Re: shocking
Post by: SeanB on December 28, 2015, 06:16:15 pm
I will say nobody has been doing electronics for a long time and has never had a non fatal shock.  Of course the system is somewhat self selecting, as those who have had a fatal shock tend not to be able to post here any more. But aiming to avoid it is good, just be careful and learn from others' experience.
Title: Re: shocking
Post by: tggzzz on December 28, 2015, 09:06:26 pm
Holy hell this thread scares me. I'm not going to read through all the stories. I have a question... might be a stupid question.... how many of your have been doing electronics for a VERY long time and have NEVER got shocked by an ass puckering amount of charge? If no one I hope to be the first :(

There is a non-exclusive choice. Learn from your mistakes, or learn from other peoples' mistakes.

Reading the stories helps the latter.
Title: Re: shocking
Post by: grifftech on December 29, 2015, 03:44:19 am
A 2-3 INCH spark off my nose from static.