CEILING LIGHTS AND SWITCHES

Most ceiling lights are positioned centrally in a room to give general lighting.

But by adding another light, or changing the position of an existing fitting, you can highlight particular areas and enhance the decoration.

P utting in a new pendant ceiling light and switch, or changing the position of an existing one, usually presents few problems – even if you have little or no experience of electrical work.

A pendant is the most common ceiling light and consists of a lampholder wired to a length of flexible cord which hangs from a ceiling rose. Another type can be plugged into the ceiling rose – in this case the flexible cord has to have a special fitting which slots into a batten holder.

Know your system

Installing a new ceiling light requires making a simple connection into a nearby lighting circuit either by inserting a junction box or at an existing loop-in rose and then running a cable to a switch. In order to connect into the circuit you’ll first need to know how the lights in your house are wired and which lights belong to which circuit. Then you’ll be able to work out whether you can actually add another light to the circuit that is nearest to the new light’s position.

There are two principal methods of wiring a lighting circuit. In the loop-in method the cable runs from ceiling rose to ceiling rose, stopping at the last one on the circuit, and the switches are wired into the roses. With the junction box system the cable runs to a number of junction boxes each serving a switch and a light. You may well find that both methods have been used in the same circuit to simplify and reduce the cable runs.

It’s possible to connect into a nearby rose provided it’s a loop-in type. You can check this simply by turning off the power and unscrewing the rose cover. A loop-in rose will have more than one red insulated wire going into the central terminal bank of the three in-line terminal banks. However, it can be quite fiddly to fit another cable, given that the terminal banks are very small, so you might find it easier to insert a junction box in the main circuit. And if there isn’t a loop-in rose you’ll have to use this method anyway.

Earthing for lighting circuits

Modern lighting circuits are protected by an earth. But if you’ve got a fairly old system (it’s likely to be based on junction boxes), you might find that it doesn’t have one. So when you’re extending such a circuit, you’re now required to protect the new wiring, light fitting and switch by installing an earth. Consequently, you have to use two-core and earth cable for the extension, which will most probably connect into the existing circuit at a junction box. You then have to run a 1.5mm2 earth cable from this point to the main earthing point.

Circuit additions

Usually there’s a lighting circuit for each floor of a house and in a single storey dwelling there are likely to be two or more. But it’s easy to identify the individual circuits simply by switching on all the lights, turning off the power and taking out a 5A fuse from the consumer unit or switching off an MCB. When you restore the power you’ll know that the lights that remain off all belong to the same circuit.

Generally speaking, a lighting circuit serves six to eight fixed lighting points. In fact it can serve up to 12 lampholders provided the total wattage of the bulbs on the circuit doesn’t exceed 1,200 watts. This means that unless other lights have previously been added – wall lights for example – there shouldn’t be a problem of connecting in another light.

Remember, when adding up the bulb wattages, a bulb of less than 100 watts counts as 100 watts and not its face value.

The place for lights

Apart from bathrooms, where special regulations apply, you can position lights and switches in any place you like inside the house. But bear in mind they are there to fulfil a function, so switches, for example, should be conveniently located – by a door is often the most satisfactory position. Usually they are set on the wall 1.4 metres (4ft 6in) above floor level. But they can be higher or lower to suit your needs.

You mustn’t install pendant lights, especially plain pendants with exposed flexible cords, in a bathroom. This is for your safety. Flexes can become frayed, and if, say, you tried to change a bulb while standing in the bath and touched an exposed conductor you could electrocute yourself. Consequently, all light fittings here must be of the close-mounted type and preferably totally enclosed to keep off condensation. If instead you use an open batten lampholder it must be fitted with a protective shield or skirt which makes it impossible for anyone changing the bulb to touch the metal clamp.

A wall-mounted switch must also be out of reach of a person using the bath or shower. In modern small bathrooms, however, this is often impossible. The alternative is to place the switch just outside the room by the door, or to fit a special ceiling switch operated by an insulating cord which doesn’t have to be out of reach of the bath or the shower.

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Putting in switches

There is a great variety of switches available, but all perform the same function of breaking or completing an electrical circuit so you can turn the light off or on. Modern switches are of the rocker type; a one-gang switch has a single switch on the faceplate; a two-gang switch has two switches on the same face-plate, and so on. Dimmer switches are slightly different in that you can vary the power flowing to the bulb (so reducing or increasing its brightness) by rotating a control knob.

With a new light, you can either connect it into an existing switch position (fitting a two-gang switch in place of a one-gang one, for example) or a new switch. Depending on how you connect into the existing circuit, you’ll have to run the switch cable above the ceiling from a rose or a junction box down the wall to where you are going to locate it. If you want to conceal the cable on the down drop you’ll have to cut a shallow channel -which will damage the existing decoration. Or, you can surface-mount it in trunking.

Making the connection

Once you’ve decided where you want to put the light fitting and switch, you then have to decide where it’s best to make the connection into the existing circuit.

Wiring runs may require some detective work to find out what each cable is doing -you don’t want to connect into a switch cable by mistake. This may mean climbing into the roof space or raising a few floorboards. You’ll need to do this anyway to run in the new cables to the required positions. As cable is expensive, it’s best to plan your runs to use as little as possible. But when you measure along the proposed route, don’t forget to allow about 200mm extra at the switch, rose and junction box for stripping back the conductors and joining in.

Changing the position of a ceiling light is even easier than adding a new one. If after you’ve turned off the power you undo the existing rose you’ll see immediately the type of lighting circuit you are dealing with.

If there is only a black, a red and an earth wire going into it on the fixed wiring side then you have a junction box system. All you have to do is to disconnect the wires from the rose and reconnect them to the respective ter-minals of a new three-terminal junction box that you’ll have to put in directly above the old fitting. You can then lead off another cable from this junction box to the repositioned ceiling rose. The switch remains unaffected.

If the rose is a loop-in type, you have to carry out a similar modification, but this time the switch wires have to be incorporated in the new junction box, which must be a four-terminal type.

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