All the mains appliances featured here have some kind of mains cable. Problems with the electronic cables of portable appliances are quite common, especially those that are moved around constantly while in use, such as vacuum cleaners and hedge cutters.
The problems can range from a simple break in one or more of the conductors, which would render the appliance open circuit, to the breakdown of the cable’s insulating properties caused by damage, fatigue or neglect, leading to the risk of electric shock or fire. Electronic cables and extension leads must be checked regularly and thoroughly.
There are several different types of flexible electronic cable in two-core and three-core configurations on the appliances shown here. It is important to remember that two-core electronic cable is used only on double insulated appliances; three-core electronic cable is used on all items requiring an earth connection. Read the rest of this entry »
The term ‘harness‘ is used for all of the wires that connect the various components within an appliance. In large appliances they are usually bound or fastened ‘together in bunches to keep the wiring neat and safely anchored. Smaller appliances, however, may sacrifice neatness for safety and route the wiring to avoid contact with heat or sharp edges. The correct positioning of wiring also contributes to the double insulation of an appliance, so no alterations whatsoever should be made to the routing or position of the wiring in double insulated appliances.
When you first take a look at it, the harness may seem like a jumble of wires thrown together, but if you take the time to inspect it, you will find that each wire is colour-coded or numbered either on the wire itself or on the connector at each end. This allows the engineer to follow the wire through the appliance easily. With a little practice, any wiring or coding can be easily followed. 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 »
