by ericmark »
Sat Mar 22, 2008 8:56 am
Neutral is classed as "Live" and if your house is feed with a TT system you can get a difference between neutral and earth. The same applies to a TN-S system only with a TN-C-S are earth and neutral combined before entering the house. A typical electrical exam question ask for a count of "Live" wires to impress on electricians that neutral is "Live". The L you see on your plug top stands for Line not Live. Because of the harmonizing with Europe where unlike us they can plug items in either way around double pole switching has become the norm. Harmonics in the supply can produce the tingle effect at quite low volts and if we calculate the difference between max volts at the transformer and Min volts at your house you can get 36.8 volts differential between Neutral and Earth with no faults existing. Natural Electromagnetic, Electrostatic and ionizing influences can increase this. Regulation 442.2 does show how neutral and earth voltages can vary and shows how voltages can be tolerated for limited time up to 800 volt so touching the Neutral could be extremely dangerous. If you live very close to the transformer than maybe there's a fault but if on TT supply and remote from transformer then very likely there is no fault.
