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Earths can be dangerous

Why don't you answer his question? Give your own opinion, or you're the one looking like a fool.

Reply to
Mr David Clegg
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Smoooooth! :-)

Reply to
Johnny B Good

Another one bites the dust! 3 wankers in 2 days. :-D

Reply to
Cursitor Doom

You don't get paid for plonking you know. Jumping up and down with glee is pretty childish don't you think? Basically you're just getting the last word in and running away.

Reply to
Samantha Rose

And another who thinks himself so important the whole world must know who he chooses to read or not.

Care to tell us what your bowel movement looked like today too? ;-)

Reply to
Dave Plowman (News)

No point in taking someone seriously who calls themselves "Cursitor Doom". At least mine is a normal name.

Reply to
Jimmy Wilkinson Knife

Right. Answer this. If you were to lie flat on shall we say a quarter inch thickness of any plastic or glass even of your choice, onto say the garden outside or a concrete floor inside and then hold a live cable, the live of a 230 volt mains supply would any current flow and would you complete any circuit?..

Reply to
tony sayer

240 volt. 230 volt has never existed. It's an EU made up amount. They have 220, we have 240.

No. I'd get a bit of conduction from my capacitance but that's it. And yes I've done that sort of thing (by accident).

State the resistance of that substance you've fictitiously made up and do a calculation in front of me.

And why on earth would I be lying flat under any normal circumstances?

Reply to
Jimmy Wilkinson Knife

I love it when you manage to contradict yourself in just two sentences. First you say no, a circuit would not be completed and no current would flow. Then you say that there would be "a bit of conduction from capacitance". Either there is current flow and a circuit there or there isn't. Hint: there is

Reply to
trader_4

Yep, just what little kids do, close their eyes, put their fingers in their ears and chant "nyah nyah, can't hear ya"

Yep.

Reply to
Rod Speed

Thought that was down to cables running diagonally across a wall, rather than vertically or horizontally between fittings?

Proper conduit would be fairly hard to drill through. Not so sure about the thin top hat stuff once used - if drilling with a universal bit.

Reply to
Dave Plowman (News)

The cable was diagonal, but a metal channel would have stopped a standard masonry bit. The sheet deforms and a relatively blunt masonry bit simply stops.

I don't recall when the rules about safe-zones were implemented but believe it was post MP daughters death, and definitely post wiring in her house.

I've been told SDS bits can go through galvanised channelling somewhat more easily than masonry bits.

Reply to
Fredxx

Yes, but that's the whole point, really. When something like this happens, investigation leads to changes to the regs to prevent it happening in future. I know they're not perfect, but on balance, we are better off following (the latest) set down procedures. I'm really surprised more sparkies haven't chipped in on this thread.

Reply to
Cursitor Doom

Some sparkies love the regs as they can make a mint just inspecting stuff and not doing any real work. The sparkies without the proper "training" and silly certification just get pissed off that they have to pay someone else to finish off a perfectly well done job.

Reply to
Jimmy Wilkinson Knife

I prefer equipotential bonding in a bathroom over the RCD protection that is now allowed.

Reply to
ARW

ISTR that you are a time-served sparks. What do *you* make of the OP's idea of disconnecting all earths from his appliances?

Reply to
Cursitor Doom

I would be delighted if he did so and killed himself.

Reply to
ARW
[snip]

I've heard the voltages called 115/230 long before these was such a thing as EU.

[snip]
Reply to
Sam E

IDK how much more you want. It's been discussed and explained. It's a really stupid idea. Let's say you disconnect the ground from the dishwasher. Now the metal frame is ungrounded. If there is a fault where a hot comes in contact with the metal case, now that case is hot. If you touch that case while touching a metal outlet plate, the sink faucets, another grounded portable appliance that someone plugged in and left of the counter, you can get shocked and it could be fatal. With the ground in place, the hot will typically cause a high fault current that will open the breaker, indicating a problem. And even if it does not because it's not a dead short, the metal case of the dishwasher will not be energized, you could touch it and the water pipe and not get shocked.

With his alternative system, the dishwasher remains hot for an indefinite time, could be years. Imagine another appliance at the other end of the house then developing a similar fault, only this time it's the other hot side that gets shorted to the case. Now the two appliances both have energized cases on opposite sides and are looking for a path to complete the circuit. That could be water piping, metal ducting, steel building material, a coax TV cable, an ethernet cable. If those have good conduction, it trips one or both breakers. If they don't have good conduction, there is resistance at some unknown spot in between, like at a coax junction, then it gets hot and could pull whatever the current rating of the circuit is, creating a fire. Or you could be undoing a cable connection and you wind up in the circuit. That's why his system isn't used.

That lead into the more general discussion of why we use a system where neutral is tied to earth ground. It's main advantage is that with one conductor tied to ground, there is always an easy and direct path for an unexpected high energy fault to be directed safely away. For example, if you have an overhead service going into the building and it's neutral is earth grounded, then if it gets hit by lightning there is a direct path to earth most of it safely, so it never enters the house. Again, imagine a service that was isolated getting hit by lightning instead. Now where does the lightning energy go?

There are advantages and disadvantages to grounded and ungrounded systems. But like you said earlier, the experts have considered it all, looked at real world data and decided that the earthed neutral system works best. And some of what JWK claims, I'd like to see him try. He should go into an industrial setting that has an ungrounded circuit for a particular piece of equipment, grab one of the conductors and grab the metal case of another piece of eqpt or a water pipe and see what happens.

Reply to
trader_4

So only those with weak hearts are thus affected?, I bet you won't find any medical reports on electrocution to back that up;!

Our hamster when i were a lad went and chewed the cable to the TV it blew his head apart poor little thing!.

No earths were involved in harming that animal;!.

Reply to
tony sayer

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