Basic home electrical maintenance

In general it is not advisable for the inexperienced to attempt electrical repairs. The dangers to life and to property are too great. Additions to wiring and most repairs should be carried out by the manufacturer’s approved service agents, or by a qualified contractor from the Electricity Hoard or one who is listed on the roll of the N.l.C.E.I.C. or is a member of the E.G. A.. or both. You can sec a list of approved contractors at your local library or electricity showroom.

Tasks which you may be able to tackle yourself, provided you feel sufficiently competent include:

Wiring a plug

Shortening a flex and putting the plug back on Checking the wiring connections within a plug Replacing the fuse in a plug Mending a fuse in the mains fuse box

Before investigating or repairing any electrical wiring or appliance, always turn off the electricity at the mains. The mains switch will usually be fixed close to your meter and fuse box. You may have more than one if, for example, you have a separate circuit for night storage heating. Make sure that all switches remain accessible.

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Always keep these as short as is practical. Long flexes trailing on the floor may trip people up; on a work surface, they can be pulled at by a child, or could get in the way of a hot surface such as a cooker; they could also dangle into the sink. You can shorten a flex yourself if you know how to put on a plug correctly. You should not try to lengthen a flex: have this done by a qualified electrician.

Never tape two flexes together with insulated or plastic tapes. Do not wind flexes tightly around appliances, in particular those that are still hot, such as an electric iron or electric fire.

The conductor wires in the Rexes of appliances bought after June 1970 are-coloured as follows, according to an internationally-agreed code: brown for Live blue for Neutral green/yellow twist for Earth

Learn this colour code: it is vital when you come to put on a plug, see below.

Old appliances may still have flexes coloured according to the old wiring colours: red for Live black for Neutral green for Earth

Putting on a plug

Don’t try to do this seemingly simple task unless you know that you can do it correctly. You must feel completely confident. A survey by a leading manufacturer of electrical fittings has revealed that around a quarter of the plugs in British homes are likely to be incorrectly wired. A plug that is not properly connected is potentially dangerous to you and your family, and will affect the working of the appliance to which it is fitted. Always buy plugs marked with the letters/numbers BS 1363. This refers to the relevant British Standard for quality and safety. Cheap foreign imports may save money initially but could overheat, causing a fire or even costing a life.

To put on a plug you will need a pair of pliers, an electrical screwdriver and a sharp knife. This is what you do:

– Unscrew the back of the plug, put the back of the plug on one side; place the screws in it so they do not get mislaid.

– If necessary, carefully cut away 5 cm of the covering from the end of the flex, to reveal the inner coloured wires. If the flex is of the braided type, wind insulation tape around the cut braiding to prevent it fraying.

Cut away 1 cm of insulation from each of the wires in turn, working very carefully so as not to damage the thin strands underneath, then twist each set of exposed wire strands into a neat spiral -ensuring that no wire strands escape.

– At the bottom of the back of the plug you will find two large screws that control the cord grip. Loosen these sufficiently to allow you to push the flex through, under the grip. The flex must penetrate the plug sufficiently for the cord grip to clamp down onto the outer covering of the flex, not onto the inner wires. In some plugs, there is simply a nylon safety grip, into which you push the flex firmly.

– Run the brown wire to the Live pin on the right with the cartridge fuse, marked L. Run the blue wire to the Neutral pin on the left marked N.

Run the two-coloured green/yellow wire to the Earth pin at the top of the plug, and marked E or with the Earth sign:=t. NOTE. Some appliances are double-insulated and do not have or require an earth connection. Typically, these include vacuum cleaners and hairdryers. They will be marked on the rating plate with the double-insulated sign, which is a box within a box.

– Different makes of plugs have different ways for you to attach the wires to the pin ends. If the pin ends have holes with little screws, bend the ends of the wires back on themselves; loosen the screws, push each wire through its terminal in turn, tighten ing each screw as you go. If the pin ends

Different makes of plug require different methods of attaching the wires to the pin ends, as shown and explained in the text Above: correctly wired three-pin plug have washers held down by screws, twist the bared strands tightly together and wrap each one in turn clockwise once around the screw of its terminal underneath the washer, then tighten the screw. Always make sure that there are no loose bits of wire, and that the fuse is of the correct rating, see above. 6. Finally, replace the back of the plug, and secure with the scrcw previously removed.

You can lengthen the flex of an appliance by using an extension lead ; this will have a plug fitted on one end and a socket on the other. Always use an extension lead rather than trying to join on lengths of new flex; better still, have extra power points installed so that you do not need to use a lead. Never leave an appliance permanently connected to a socket by means of an extension lead.

If you must use adaptors to make electrical connections between plugs and sockets of different types, be sure that these have proper earthing connections, and fuses. Better still, change the outlets to 13 amp 3 pin pattern.

Do remember that if you still have sockets in your house with round holes, it is likely that your wiring is now unsafe and you should have it checked, with the view to having your house rewired.

An adaptor will also allow you to connect two appliances to one socket. But – and this is a very important safety point -the total electricity in watts used by the two appliances together must not exceed the rating of the socket into which the adaptor has been plugged. The wattage of each appliance is marked on its rating plate. A 13 amp socket outlet can supply up to 3,000 watts. If you exceed this figure you could start a fire through overheating of the socket and the adaptor. As with extension leads, you should aim to install extra socket outlets rather than rely upon the use of adaptors.

Changing a light bulb

Before changing a bulb always turn the light off at the switch. Be particularly careful with bathroom pullcords. When the bulb has failed you know that the switch is ‘on’ and you should give the cord a single tug to turn it ‘off. However, if you start tugging indiscriminately, you will have no means of knowing whether the switch is offor on; in which case it is safest to turn the electricity off at the mains.

If the bulb has recently failed, remember it will still be very hot: protect your hand with a thick cloth or wear gloves. Domestic light bulbs are usually of the bayonet type: two small projections on the bulb fit into the slots in the bulb holders. To free the failed bulb, carefully push slightly upwards and turn anti-clockwise. Press in the new bulb, and turn clockwise until you can feel that the bulb is fitting securely. If the old bulb has broken off inside the holder you must first turn off the electricity at the mams. Protect your hands with thick gloves, and use a blunt piece of wood to prove the bulb base and ease it free. Or push a cork up on to the bulb base and use-that to twist the broken bulb free.

There are now so many different types of bulbs on the market that you may find it easiest to take your old bulb with you when shopping for a replacement. Buy two or three bulbs at a time if you find you have a type difficult to get locally. Never replace a bulb with one of a higher wattage than the maximum specified as to do so could create a fire hazard.

Occasionally, fittings may require ES bulbs which are screwed into place clockwise and removed anticlockwise. This type of bulb is commonly fitted into refrigerators. Turn off appliance at the wall, before unscrewing the failed bulb and taking it to the shop to buy a replacement of the same type.

Fluorescent tubes should last for three years or more. Buy the colour marked warm white de luxe for normal domestic use. Tubes starting to blacken at the ends will shortly fail: you should also replace tubes that glow red at the ends or flicker. Replacing a tube is very simple. Turn off the switch. At one end, carefully case the tube inwards to disconnect the two pins at its end from the plug in the fitting which holds them; then repeat for the other end. Fit the new tube in similar fashion.

The starter, a small round plug on the top of the tube holder, may need replacing if the tubes start to glow white at each end without lighting up, or if a newish tube flickers or keeps switching itself on and off. To remove the starter, turn off the light, then twist the starter anti-clockwise. Take it to an electrical shop and buy a replacement of the same kind. This is fitted simply by inserting it into the tube holder and twisting clockwise. 159

Basic home electrical maintenance