Shocking! (ok, it's another google video :p)

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Soldato
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penski said:
Saw that a while back...Still can't decide if it's genuine or not :/

*n

I would say it is. They do make giant electricity things like that when they get turned on.

Im not an electrician or electrical engineer though
 
Soldato
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Read this feasible explanation somwhere else:
This is probably normal for opening a switch with that much voltage across it. As the switch first swings open, the gap is very small and the voltage makes an arc as it breaks down the air (turning it from an insulator to a conductor.) Once this arc is established it grows in length as the switch is opened further since most of the air between the switch contacts has already been rendered conductive. Notice that the arc rises as time goes by because the arc heats the air and hot air goes up. The arc goes through the longer path because that hot air that is rising is still more conductive than the cold air down below which replaces it. Eventually the conductive air rises enough that the path through it has to also go through the colder non conductive air and this breaks the arc.

And here is a 345Kv switch opening :)

//Edit: In fact for all your big electricity spark needs check here!
 
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Yup, that is exactly what happens when switches that size open....i've had the 'unfortunate' experience of working on a 400kV one! :(

Theres a fair delay before the switch is clear...
 
Soldato
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That sort of only happens when it's opened under load, which shouldn't be done really as it can wear down the contacts. I think I remember reading somewhere that it was caused by a fault, but I thought most switches were submersed in oil anyway.
 
Associate
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Evil-Penguin said:
That sort of only happens when it's opened under load, which shouldn't be done really as it can wear down the contacts. I think I remember reading somewhere that it was caused by a fault, but I thought most switches were submersed in oil anyway.

It's normal for HV switches to be switched in oil (up to 33kv) when on load but in substation compunds and in remote places "air" is the prefered insulator as it's cheaper :) and dosen't require looking after. Also substation oil switches for 11kv can be closed on load/faults, this is when you have a long piece of string so that you are standing out of the substaion when you close the breaker in on the load / fault. In remote locations it's normal for the breaker to close in upto about 6 times automatically just in case it's a transient (sp) fault.

on 11 and 33kv Mast switches should not be closed in on faults, for saftey reasons, however on 11kv nowadays you have smart fuses and links which work in fault conditions.

cheers
Deano
 
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