A basic understanding of electricity is essential, even for those who do not intend to carry out any repairs or servicing of appliances. Ignorance is no protection against your own or someone else’s errors and oversights, whether with repairs, servicing or installation.
Power is supplied to an electricity substation at a very high voltage — 400,000 volts — in three-phase form. There it is converted, via a transformer, to 230 volt single-phase for distribution to our homes. In normal circumstances, current flows from the live supply of the substation’s transformer, through the electrical appliances used in the house and back via the neutral conductor (cable) to the substation transformer’s neutral pole (a closed loop). Read the rest of this entry »
Low insulation is best described as a slight leak to earth of electricity from the wiring of one or more of the components or wiring in an earthed appliance. If very slight, it will not harm the appliance but is an indication of faults to come and should be corrected immediately for safety reasons. The condition occurs during the progressive breakdown of the insulating properties of a normally electrically leak-proof system.
It may be caused by normal wear and tear over a long period, resulting in a breakdown of the insulating coating on wiring, motor windings, heater elements, etc. Such a breakdown of insulation may not result in a failure of this part at this stage and the appliance may still function as normal. This, however, is not an excuse to ignore low insulation; failure to trace and rectify it is foolhardy because it compromises safety. Also extra expense is likely to be incurred in the long run. Read the rest of this entry »
