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I am interested to know how often very experienced DIYers receive serious shocks.Why did it happen? Was it avoidable?
Do DIYers ever die of this?
Follow Ups:
Show respect for electricity. Some time ago a person posted a horrible story of the conequences, not instant death in his case , but slowly rotting away with failing inner organs/lungs..due to internal burns...I use rubber shoes, gloves, long sleeves, and one hand in my pocket when measuring live equipment..
15 year ago I pulled a fuse from a live power supply, 230V shorted through me, luckuly the safety switch+fuses in my electrical cabinet tripped and possibly saved my life..
Dont work when your tired and keep one hand in your pocket until you become familiar with the HV spots.Usually its things like axial lead filter caps that give you the poke because they are slopped in a lot of times and even run low voltage areas where you dont expect to get a 450v poke.
I did something oh-so-stupid and nailed myself with a neon sign xformer last weekend...does that count?
Tossed me a couple feet, whole body was sore for a couple hours and heart rate was way up for a couple minutes...
This past Saturday. I reached behind my amp to check an interconnect while the cover was still off. My forearm touched the top of a capacitor bank. 330 volts. The piece was turned off but I hadn't discharged the caps. Ouch.
The last time was in 1976. 450 volts in one thumb and out the other. The piece was unplugged but I hadn't discharged the caps. I ended up on my butt across the room. Ouch.
Patience is the toughest thing to learn.
About 1999
Touched the 450V B+ in my amplifier by accident, then threw my arm back, which caught my power supply's umbilical cord, knocking the amp on to the floor, where it landed on my toes, corner first!!The amp suffered a broken Japanese EL34, and I had to lay down for about an hour!
About 1993
Tandber 64X... touched the B+, hurt like hell, and had to lay down for a while as above, but not nearly as bad!
Frihed89I just got shocked with B+ about 2 weeks ago.
Nothing new for me though.
I can take 120Vac with no problem but
I know I am weird but still don't do it on purpose
anymore which I did many times when I was a kid.The most voltage was discharging a CRT - ~20KV.
(I was incapacitated for almost an hour)The most current was discharging two capacitors
the size of car batteries in the rain.
(I still have the scar to prove it)The most painful was 440VAC 400 Hertz from a
6 cylinder deisel generator.
(They don't call it HERTZ for nothing - It HURTS)These were while I was in the Marine Corp
while troubleshooting on a Radar System.
Nothing since then compares with these.I think the worst was when my mother's cellar flooded
and the sump pump had tripped the circuit breaker.
I had the stand in a couple feet of water holding the pump
above the water line while being shocked with 120VAC.
NOT recommended but it needed to be done.
But then again I am not the norm and I know it.
My mother said that I used to unscrew lightbulbs and
stick my hand in the socket when I was very young.
She had to put ointment on my burns several times.
I do not remember this but I don't doubt it.My right hand makes a very good TV antenna and
my left hand makes a very good FM antenna.
BUT the opposite isn't true.
Go figure.
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DanL
Lets see... I was shocked by trying to discharge a TV cathode ray tube about 20KV but very little current and about 560V from the power supply of a homebrew 6550 amp I was building. The latter one came from a capacitor bank consisting of two 1000 uf computer grade electrolytics connected in series. A lot of current must have flowed through my body then but I'm still alive. After that shock, about 20 years ago, I have been specially careful avoiding them with no more ocurrences whatsoever.
I got shocked by my first tube amp when I was 19 - 450 volts across my fingers... when I first started doing DIY stuff, I got shocked several times but now I follow good safety practices and haven't been jolted for years.
actually a few thousand volts, but practically no amps. Fortunately have not done that with any project I've built and hope never to do so. I'm fairly paranoid about discharging any power supply with a resistor held with an insulated pair of pliers and touched to both terminals of a power supply cap. I also measure the voltage to make sure it's down to a few volts before touching anything else inside.
I was trouble shooting a small amp that had current source loads on the tubes...I was having trouble with the transistors on the current source board and as I looked at it, thought to myself, 'wonder if that thing is running hot?' and touched it. Now, this was way stupid on two levels, since it could have been almost blistering hot, and, as I discovered, had some DC on it (metal case transistor)...Lucky for me it was relatively low voltage, and all I got was a humbling lesson learned...
CaffeinatorI have used that troubleshooting techique.
Although I didn't have anything else grounded
and I just licked my finger first.
If it goes TSSS then I know it's overheating.
No current and no burn.
About 50 years ago I would have to say once a month or so. Now once every couple of years or so.
Why? Carelessness!
Was it avoidable? Absolutely!
Do DIYers ever die of this? Probably but I don't personally know of any.
Advice? Be careful, set up a safe bench and employ the one hand rule.
Maybe in another 50 years I will learn and employ these principles but at my age the occasional jolt is probably what keeps my heart pumping.
There are ways to avoid shocks that must be remembered, all the time.
The warm, sweaty weather is coming up. That is when your body is the least resistive, when it is hot and sweaty. All shocks could have been avoided !
Sparing the theoretical, you must not let any part of your body be the conductor. You cannot even let your finger take high voltage from one point to another, or to ground, or let your arm rest on the chassis.
Let's see what happens when you lean the chassis sideways, on your arm/body, while checking underneath the chassis, with your other arm. Let us say that you are probing voltages, carefully, with the other arm's hand. You happen to touch a high voltage point. Well, the current available from that high voltage point now travels through your hand, ACROSS YOUR HEART, to your other side, where you sloppily leaned on the chassis. That jolt is DC, which sucks in the body. Flinching away, with hot DC is not easy. That jolt can do more than start your heart. It can stop your heart. Plus, the burn marks, now on your body, from the point of HV contact, as well as the point you touched ground, can be serious.
So, Remember the one hand rule. Keep one hand in your pocket. Secure the chassis on your workbench, not your body. Probe with one hand, only. If the chassis even looks crowded, wear tight leather gloves. Those finger shocks can be bad. Avoid them, please.
The negative lead of the meter should be secured to chassis ground, or the negative reference point that you are using(actual tube bias is measured from cathode to grid), with a tight alligator clip.
Think SAFETY FIRST ! It may save your life. I know many, very qualified, electronic techs and electricians that have suffered severe shock burns. Please don't be added to that list.
There are many books and lit available on electrical testing safety. The more knowledge you have, the more confidence you will have. If you are scared, you will undoubtedly shake, which is a shock in the waiting. Be Aware and be confident, or don't play techie at all...
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