Talk:Electrical bonding

Quote: "This is done in the UK because many buildings are supplied with a single phase supply cable where the neutral and earth conductors are combined. Close to the electricity meter this conductor is divided into two, the earth terminal and the wire going to the neutral busbar in the consumer unit. In the event of a break in a neutral connection this earth terminal provided by the supply company will be at a potential (relative to the true earth) which is the same as the live wire (phase wire) coming to the home." I think this is factually incorrect. (1) In the UK, the neutral conductor is earthed at the sub-station but it is not combined with the earth conductor. (2) A break in the neutral wire could result in the neutral terminal becoming live but I don't see how it could result in the earth terminal becoming live. Biscuittin (talk) 20:15, 4 April 2008 (UTC)
 * You are wrong, combined neutral and earth cores are very common in distribution wiring in the UK (especially in newer wiring, the old lead sheathed stuff tends to have seperate neutrals and earths though sometimes even there the neutral is used for earth).
 * http://i69.photobucket.com/albums/i62/RFLighting/PMEcutout2.jpg is a picture of a fairly typical service head (with the lid off), you can see the service cables (service heads are often daisy chained) at the bottom with their live and CNE cores and the installation cabling with seperate neutral and earth leaving from the top and sides. Plugwash (talk) 14:45, 5 April 2008 (UTC)

It looks as though you are right but I am astonished. If I wrote the rules I wouldn't allow it because (as mentioned above) of the risk of the earth terminal becoming live. Bonding may alleviate the risk but why create the risk in the first place? Biscuittin (talk) 18:34, 22 April 2008 (UTC)
 * Do you know when the rules were changed to allow combined neutral and earth? I suppose it was done to save money on cables but it seems absurd to create an unnecessary risk and then have to find a solution to it. Biscuittin (talk) 20:16, 22 April 2008 (UTC)

I think what the author is trying to say is that when there is a break in the neutral, and if the live conductor touches the metal casing (which is bonded to the earth conductor) of an equipment, the live conductor and the earth conductor will be at the same potential. This significantly reduces the touch voltage which a person will be subjected to if he touches the metal casing. (SZW) —Preceding unsigned comment added by 218.186.244.160 (talk) 17:26, 17 May 2008 (UTC)