Would touching electric wires from the mains, kill you?

[Lobos 10]

Was it colour or black and white? You would get a nasty burn from the top caps of the line output valves, they're a few kilovolts AC, but the supply from the EHT tripler to the tube is something else, 25-30 kilovolts DC from a stabilised power supply which means that even when you load it with your arm it still delivers enough current to kill.

It was the old pye hybride 205 chassis with the big convergence panel and the upright line output panel....not sure where my hands went I think on the back of the line output printed circuit...I'm still here after that though...

 

---------- Post added 03-04-2015 at 00:21 ----------

 

At one time these type of TVs had a different mains connections Pye colour sets,as they came from the rental market we had to solder new wires to the power supply,we bought these ex rental sets in large numbers for resale on the second hand market,one day while refurbing a load of these sets I had soldered a new wire to this particular set and done the necessary work to get it ready for sale and put the set on the test bench when a customer rang up,after a lengthy phone call I returned to the TV to put a mains plug on it,unbeknown to me my workmate had moved the set up on the bench to put his TV on the bench and swapped the mains plug over,I thought I had switched the mains off and got hold of the live wire took my side snips out and cut the live wire with them...Bang;;the snips shot out of my hand hit the roof as all the lights and all the TVs on show in the showroom went off with half a dozen customers in the show room left in the dark...luckily the side snips were well insulated or I might well have had more than a burnt finger.

Edited April 2, 2015 by Lobos

[rockonvynil 10]

http://www.greenbrook.co.uk/pdf/pbcatpg21-22.pdf

 

rcd operation explained

[DrNorm 10]

Would touching electric wires from the mains, kill you?

 

No, not usually, but it sure wakes you up in a hurry.

 

I was once given the job of fitting bleed resistors to mains filters on equipment that was retaining charge after being unplugged. Customers were getting a shock from the plugs after removing them from the wall socket.

 

Procedure: Power down the system. Switch off. Remove plug from wall socket. Use screwdriver to clear retained charge. Solder bleed resistor between live and neutral terminals on the mains input filter. Customers no longer vulnerable to unexpected shocks.

 

NB. Please remember step 3. Don't miss out STEP 3. Step 3 is very important.

 

I once forgot step 3 so was putting my screwdriver across live and neutral. Yeah that made me jump. Customer didn't actually see what happened but was prompted to ask "are you OK". "Sure I said, just a bit of static"

 

(Days before RCD breakers were common). You'll be pleased to know I'm not in that line of business any more ...

 

---------- Post added 06-04-2015 at 19:55 ----------

 

Just get hold of a electric fence, it wont kill you but it will make jump

 

Yep, done that too. I was out walking and the group decided to take a short cut, as we'd missed a turn. I didn't realise the fence was electric as somebody went before me without consequence. Now there's 2 of us on the wrong side of an electric fence and of course nobody else will follow. So we had to go back through ... It's only 50V I've been told, so just a bit of a Jackass stunt really.

[BluePolo 10]

It can kill you.

 

If the current goes across your chest i.e. from one hand to the other, the shock can affect your heart.

My worst shock was when I'd removed a panel from a large piece of equipment & the panel was earthed, so the I was sat on the panel, leaning over with my weight on one hand on the panel.

 

Reaching inside to to slide something from the back to the front, my finger touched on the main incoming terminal - which had a guard covering the top and front (but unbeknown to me, not the back. My arm muscles immediately went into spasm and I couldn't move them. I could smell my flesh burning. To release myself all I could do was shuffle my backside away, pulling my hand away from the terminal.

 

20 years later I still have a dimple on the end of my finger where the electricity burned in. The worst injury (pain wise) was where I ripped the skin off my finger by digging it into the sharp corner of the guard covering the top of the terminal (obviously I still have that scar as well).

[DrNorm 10]

You never forget an electric shock! Fortunately however, most accidents with electricity are not fatal - I still don't recommend taking the dangers lightly though!

 

Your story reminded me of a fellow engineer who was repairing a computer printer on a company director's desk with the covers removed and the power switched on while completing tests.

 

The director returned and demanded he take the printer off his desk immediately. My colleague picked the printer up, got an electric shock and dropped the printer to the floor, damaging it beyond repair. (Hopefully there's still some humour there without the original colourful language that the story was first told!)

 

---------- Post added 06-04-2015 at 21:20 ----------

 

Oh and then there's the one about our physics teacher who was stood on an upturned bowl with both hands on the Van der Graaf generator to demonstrate static electricity. you know the hair goes all frizzy and stands up on end. One flaw in the safety plan was that his nether regions were too close to the gas tap on the lab bench. The charge found it's way to earth via the path of least resistance which in this case was his wedding tackle. I wasn't there, but I do hope it's a true story. The animated way in which the story was told tells me it is.

Edited April 6, 2015 by DrNorm

[GLASGOWOODS 10]

Being an ex TV repair man I've had a lot of electric shocks in the past,I think the one of the worst one was one day I was in a customers house with the back off one of those big cabinet pye TVs,when the lady opened the kitchen door and let the dog out it was a big daft spotty dog,it came running up behind me and leaped on my back pushing me with both hands outstretched into the back of the switched on TV,the one with the big glowing line output valves and lethal EHT tripler,I got a right shock the power went down my arms and because I had out of courtesy took my shoes off in the house shot through my body, I could feel my hair stand on end,I was lucky to survive that one...

 

That's what you call live on tv.

[Cyclone 10]

I bridged a capacitor on the back of a circuit board with my fingers by accident, it only snapped across my hand, but it actually burned little pits into the sides of my fingers where it arced from one finger to the next! That stung.

[shaunyp 10]

I think anything over 200 milliamps will kill you if touching the live with your finger and the floor with feet.

Although if you have an RCD on the circuit at your consumer unit, which protects the circuit, then this will trip out before that amount of current flows.

RCD's (Residual current device) are rated at 30milliamps, so they will trip out before anything like 200mA flows.

[Obelix 11]

60mA is sufficient to kill you if it flows across the chest. Just a couple of mA in the heart itself can disrupt normal sinus rhythm.

[Berberis 10]

If you accidentally touched the 2 electric (mains) wires, that connect to a light fitting; just for a split second, yes, you'd presumably get a shock, but would it be bad enough to kill an healthy adult?

 

Not really. Im speaking as a person who has had over 500 volts go up one arm and down the other, i.e. across my heart. Much to my dismay I did not develop any super powers.

 

Your mains is AC, so a jolt is only for a split second as your feed is oscillating at 60Hz (60 times a second), so even if your muscles caused you to grip, you would immediately release the electrode, disconnecting you from the supply.

[Cyclone 10]

What? Just, what?

[shaunyp 10]

60mA is sufficient to kill you if it flows across the chest. Just a couple of mA in the heart itself can disrupt normal sinus rhythm.

 

I think it is medically proven that anything from 200mA is the KILLER, anything less may kill you, which is why electrical companies produce RCD's set at 30mA which lets fault current flow to a maximum level of 30mA for a fraction of a second until it trips the system in 400 mS.

Although any shock from an energy source whether including an RCD or not...isnt a good thing !!! I sure dont like em anyway !!