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Children get electrocuted by sticking things into outlets,
and houses burn down from wiring faults and when rodents
chew the lines. I propose a system to simultaneously
improve safety and reduce the cost of house wiring.
The discussed system would consist of individual circuits
for each outlet
in the house. The outlet would have
additional connections for equipped devices. One line
would have a small 5 V output going to the outlet at all
times, and this would not draw enough current to burn or
electrocute. A "smart" device attached would either send a
return signal to acknowledge that a proper device is
connected, or the system could be as simple as shorting
two legs to trigger a relay in the breaker box. (Such
communication could even be wireless.)
With this extra redundancy, the typical 120 V or 240 V
circuits could be changed to 1000 volts or more, reducing
the current drawn and the amount of conductive material
required to carry the power. This would reduce the size of
neighborhood transformers while running off of the same
grid for legacy users.
[link]
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I'm not sure I see this being cheaper. |
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It's cheaper because it reduces the cost of heavy
gauge wiring and large transformers. |
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I don't see this being cheaper or safer. The kind of insulation and circuit design that must be used to prevent voltage "leaks" on even modest 440V volt loads is quite dangerous. This system would also require hundreds of redundant relays which, should they fail, would turn a regular outlet into a fiery death machine. The entire electrical infrastructure, every jot and tiddle would need to be replaces, as well as every single electrical device. Strong to the negative. |
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//Children get electrocuted by sticking things into outlets// |
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//the system could be as simple as shorting two legs to trigger a relay in the breaker box// |
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Electrical standards already vary wildly between different countries. If this was implemented I'm sure every country would come up with its own standard, causing even more grief for manufacturers who want to produce electrical goods and sell them worldwide. |
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That said, it may be possible to come up with something simpler which is mechanically and electrically compatible with existing systems. For instance each wall socket could incorporate three small plastic pins, connected to microswitches in the socket, which are pressed in by the body of the plug when it's inserted. The switches are wired up so that the line voltage is disconnected until all three pins have been pushed in by the presence of a plug. A child who sticks a screwdriver into the socket is very unlikely to press on all 3 pins at the same time. |
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Alternatively you could use 3-prong plugs, with an earth prong that's longer than the two power prongs, and the socket could have mechanical shutters that cover the two power holes and are opened by the earth prong. This one is thoroughly baked in the UK. |
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// Children get electrocuted by sticking things into outlets // |
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It's called "Natural selection. |
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// would turn a regular outlet into a fiery death machine // |
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What [Wrongfellow] said. And what [MaxwellBuchanan] said. |
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Also, all new installations in the UK are RCD protected and
earthed from here to buggery and back which, as I
understand it, makes it extremely difficult for even the most
determined child to electrocute themselves, even if they
get past the earth-pin-interlocked shutters on the sockets. |
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OK, I tried to find data on deaths by electrocution in the
UK. I could only find Northern Ireland, which has similar
electrical standards. |
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There were 50 accidental electrocutions over a 22-year
period, or about 2 per year in N.I. Of these 50, only *one*
was a child - a 17-month infant killed by a wrongly-installed
circuit in a caravan. Most of the electrocutions were
amongst men (98%) and 58% were work-related. Faulty
appliances were blamed in many cases. |
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So, in N.I., *no* deaths have been caused in the last 22
years by children poking things into electrical sockets. |
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//t's called "Natural selection.// what's "natural" about it ? Breeding for luck again, are we ? remember how that turned out last time... |
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Life has a series of assumed risks that are life-threatening in the event of a malfunction. We can only hope that we are careful to not sacrifice fun, convenience, and the overall purpose for the sake of safety. There are already too many warning labels and rounded corners on devices that make life easier. |
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We would pay a dollar to see that. |
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Are you on 220v or 110v? Was the system RCD protected?
Also, it shouldn't have made his hair stand on end unless it
was several kV.... |
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My first scientific experiment (age 5ish): trying to see how
fast a teaspoon would conduct heat by touching it onto the
element of a radiant electric heater. Conclusion: electricity
travels faster than heat. No RCDs in those days. |
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Excellent experiment, [MB]. My mother relates hers, similar age, back home from the dentist with new shiny strong teeth, drinking a glass of milk and wondering whether the new teeth were strong enough to bite through the glass... conclusion: yes. |
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I hypothesized on the nature of what might happen if a paperclip were bent into a U shape, and pushed into an electrical socket once. |
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Conclusions:
1:I am in fact faster than the volts.
2:Obviously not by nuch though, as the paperclip shot across the room and dented a bookshelf.
3: Warnings against putting metal in an electrical socket are probably justified. |
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ye_river_xiv i did that in grade school but i was smart, i made the paperclio wrap once around a pencil for insulation and holding the pencil pushed it into a socket built into my desk. it shorted wonderfully quick and blew the fuse for the room. nobody knew it was me ;P |
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as for the idea, i think 100 years ago they worried about the same thing and installed switches for every outlet, some houses still have them but nearly all were gotten rid of before 1950. |
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//as for the idea, i think 100 years ago they worried about the same thing and installed switches for every outlet, some houses still have them but nearly all were gotten rid of before 1950.// |
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...Uh, are you saying your outlets don't have switches, ie are always on? Yeesh, in australia all outlets have switches, wouldn't have thought it was any different elsewhere. |
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//Also, all new installations in the UK are RCD protected and earthed from here to buggery and back which, as I understand it, makes it extremely difficult for even the most determined child to electrocute themselves, even if they get past the earth-pin-interlocked shutters on the sockets.// |
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Yes, and no. An rcd detects earth leakage, ie current passing from an active terminal to earth, without passing through the neutral. So, if you're sufficiently insulated from "ground" (ie wearing good rubber soled boots on carpet, or similar) and find yourself completing the load circuit between active and neutral (ie a fork in each hand, one in the active pin hole, one in the neutral) - you're toast, so long as you don't trip the overcurrent fuse, which you won't. |
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I've had this argument before, most memorably with the unqualified person running the "electrical safety" course on a mine site I was visiting. This idiot was trying to say that there's no way to be electrocuted with an RCD in place. Most "fiddling with the socket or wires" incidents will involve you being part of the earth-loop, but sometimes not. Laying on roof insulation working on incorrectly isolated wiring is one way you can be sufficiently insulated from earth to not trip the RCD, for instance. Or getting between welding leads, or when suited up for HV work in a substation, or etc etc. |
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As to the idea, meh.. build a better system, they'll just build a better idiot. |
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Aside from every other concern properly raised heretofore, that'd be a hell of a big bundle of wires coming out of the main panel. Bad enough as it is, with large numbers of outlets. Oh, and the panel would need to be about 5 to 10 times larger than it is now; would take up a whole wall somewhere, just to house all the new breakers. |
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//Laying on roof insulation working on incorrectly isolated wiring is one way you can be sufficiently insulated from earth to not trip the RCD, for instance. Or getting between welding leads, or when suited up for HV work in a substation, or etc etc.// |
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I wouldn't have thought that even the most determined child does these things very often. |
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