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Post by silverdragon on Jul 6, 2014 9:09:02 GMT
I have posted this here from the news thread, 'cos I think it deserves investigation, what can cause an "Explosion"..... in Electrical failure....
If you look at the Pic, that one hell of a big boom..... I know Jamie likes big boom?.....
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Post by the light works on Jul 6, 2014 21:33:56 GMT
the electricity, itself, will not cause an explosion of that nature. however, depending on what is sharing the space with the electrics...
does the UK tend towards underground transformers?
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Post by memeengine on Jul 6, 2014 23:33:40 GMT
I suspect either gas leaks from elsewhere, or shared utilities and a gas build up being ignited by faulty wiring. But as for water on its own?... even with damaged faulty wiring, I cant see an explosion this big?... You probably don't need a gas leak just enough electrical energy. I'm guessing that what happens is that there's a short-circuit and suddenly a lot of current is going through a component that's not designed to take that much current. It heats up very rapidly and vapourises...and bang! You have your explosion. Should be easily testable in any university high-voltage lab. On a much smaller (and safer) scale, I've seen much the same happen in faulty computer power supplies. Too much current through the power transistors and you have lots of plastic bits rattling around a useless PSU.
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Post by silverdragon on Jul 7, 2014 6:47:25 GMT
No, that would be overly difficult, we have outside transformers, but underground supplies.
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Post by the light works on Jul 7, 2014 14:07:35 GMT
No, that would be overly difficult, we have outside transformers, but underground supplies. yes, those transformers of ours that do not hang from poles sit on pedestals above the ground, but they do provide convenient fuel sources, if there is an electrical problem. however, a hard electrical fault is sufficiently hot to burn pretty much anything that is combustible. - including aluminum, copper, and steel.
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Post by watcher56 on Jul 7, 2014 16:13:27 GMT
Water getting into high voltage/current feeds could produce a steam explosion, but that would not produce the pictured flames.
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Post by c64 on Aug 4, 2014 15:01:36 GMT
You don't need any transformer for a big electrical fire. Of course a large transformer is filled with oil which can vaporize and then explode, but the pure electric power is good enough for a big show. The temperature of an electric arc this big is greater than the surface temperature of the sun!
Here's a trailer which had crashed into a switchboard cabinet:
Those cabinets run on 230V/400V rotary current (230V phase to ground and 400V phase to phase). The usual output of the transformers feeding many blocks are 50kA per phase. If the distance between the short circuit and the transformer is high enough, the small resistance of the feeder cables limit the current somewhat so it takes a long time to blow the fuses.
Here is an incident where a truck had crashed "briefly" into a small transformer. Those feed about 3 blocks of homes, are usually erected when a residential area outgrew a major transformer. After the crash, the box had started to smoke and after a minute, an electric fire blew off the cover. Look how far it flew away! The transformer itself didn't blow up, this as just the blast from a massive electric arc.
A transformer which blows up looks like this:
The overload from the arc overheats the transformer. When the coolant oil of the transformer boils, safety valves vent the oil-steam which ignites in the arc and causes this huge oil vapor explosion.
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