Short circuit

Can anybody explain exactly what is a short circuit and when / how could it occur.
I'm particularly interested in its relevance when bonding copper pipes.

Also please advise if I am correct that when earthing a house you take a 10mm earth wire from consumer unit to gas meter (within 600mm) and to the mains supply stop tap, and then to h & c supplies and kitchen sink.

A short-circuit would be a very low resistance between the phase and neutral conductors.

Say you were hanging a picture, and your screwed directly into a cable, the screw caused a connection between the phase and neutral wire, that would be a short-circuit. The MCB should trip.

Also please advise if I am correct that when earthing a house you take a 10mm earth wire from consumer unit to gas meter (within 600mm) and to the mains supply stop tap, and then to h & c supplies and kitchen sink.

Click to expand...

You would only need to bond things that came from outside (so to speak). Like your gas pipe, and water pipe, nothing else needs main bonding.

And, are you really from Italy? If you are, I don't think any of this will apply.

Thanks Ryanj for your reply.

I am of Italian origin but not really residing in Italy
Theres a a lot of posters on this forum of dubious origin if you care to look