Thread: Electrocution
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Steve Walker[_5_] Steve Walker[_5_] is offline
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Default Electrocution

On 30/03/2021 13:00, NY wrote:
"Brian Gaff (Sofa)" wrote in message
...
Well the key is where you take the shock. It only takes a surprisingly
small current across the chest to kill you merely by stopping your
heart, that is why the one hand in your pocket advice is so useful.
Lots of us have had shocks, mine were* usually thru the fingers of the
same hand when delving inside a working piece of valve gear that had
series fed heaters across the mains.


Ah, the perils of series-fed Christmas tree lights or valve heaters.
When all are working, you get the regulation 6 V across each one, but if
one fails and you remove it, there is near-enough the full mains voltage
at the socket (since the body resistance is so much greater than the
filament resistances).


There used to be a toy museum in Cockermouth. In one cabinet was an
early, electric, model railway. That had a controller that plugged into
a light fitting, with the removed bulb plugged into the top of the
controller, which had a rheostat. As soon as the train derailed, the
tracks would have no load and go to 240V!

Yes you get some expletives but not much else. The buzzing bruised
feeling soon passes.


With my two mains shocks it took about 48 hours before the residual
tingling had gone.


I too got one off a tape recorder - my fault, I did not expect them to
use 240V directly to power the erase head!

I've had a couple from accidentally contacting something that needed to
stay live, while working on something else in the same enclosure. Only
the tape recorder one was a proper belt, leaving me with a painful, but
numb and unresponsive arm, but only for a few minutes.

These days I've obviously improved, so none for quite a few years -
except for my boiler supply/switching, which floats at about 90V when I
disconnect both live and neutral at the supply end of the cable. There
are no other connections to either cable and boiler, so it must be an
induced voltage from parallel cabling.

Now we also have RCBOs on the non-lighting circuits and will be adding
them to the lighting soon.