Doc Hudson
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A lot of DIY problems occur around light fittings and switches and a lot can be resolved if you have a pen and paper handy and/or a digital camera. Note down everything before you undo any wires. Use a marker pen or coloured tape or anything convenient to identify particular wires or cables to allow you to reconnect them back correctly.
It is not uncommon for manufacturers instructions to not match your wiring. It is impossible for any manufacturer to know how your house has been wired. Do not be surprised if the colours in the instruction leaflet do not exactly match with the wiring colours you find at your light fitting.
2-Way switching (typically, landing and/or hall lights). To allow two switches to work the same light each switch has 3-wires not 2-wires as used in a standard switch. All of these wires are LIVE wires, some are permanent live others are only live when the light is on. They could all be the same colour e.g. Red or Brown. If it is a dual gang switch and both are two way there could be six wires all the same colour. There could also be two circuits at a dual gang switch. So with all of these possible live cables, maybe from more than one fuse, always take more care when working on hall and landing lights and switches.
If wanting to fit a dimmer switch in place of a standard switch, often the old switch back-box is not deep enough for the new dimmer switch. It can be best to open up the old switch first to see how deep it is before you buy the new dimmer.
When taking down an old light fitting there may be more than one cable, e.g. there could be supply from fuse box, supply to next light, and cable from the switch or more. Some modern fittings have very small connection terminals and it is impossible to get all of these wires inside the fitting. You may need to have a separate junction box then just a single cable to the light fitting.
When replacing a socket outlet the physical position and relative orientation of the connections may be different. One may go Live-Earth-Neutral but the replacement may be Earth-Neutral-Live. Always double check the markings on the new accessory to ensure you have the correct polarity.
It is not uncommon for DIY persons to leave screw connection a bit loose. Loose connections can cause overheating and fires. Always ensure your new cables are tightly secured in all connections. Also beware of wires pulling free when removing the front cover of an accessory if the previous screws were left loose.
If hunting under the floor for a particular circuit cable always remember that central heating control wiring can be in the same cable type as used with lighting circuits. Do not mistake heating cables for other house circuits.
It is not uncommon for manufacturers instructions to not match your wiring. It is impossible for any manufacturer to know how your house has been wired. Do not be surprised if the colours in the instruction leaflet do not exactly match with the wiring colours you find at your light fitting.
2-Way switching (typically, landing and/or hall lights). To allow two switches to work the same light each switch has 3-wires not 2-wires as used in a standard switch. All of these wires are LIVE wires, some are permanent live others are only live when the light is on. They could all be the same colour e.g. Red or Brown. If it is a dual gang switch and both are two way there could be six wires all the same colour. There could also be two circuits at a dual gang switch. So with all of these possible live cables, maybe from more than one fuse, always take more care when working on hall and landing lights and switches.
If wanting to fit a dimmer switch in place of a standard switch, often the old switch back-box is not deep enough for the new dimmer switch. It can be best to open up the old switch first to see how deep it is before you buy the new dimmer.
When taking down an old light fitting there may be more than one cable, e.g. there could be supply from fuse box, supply to next light, and cable from the switch or more. Some modern fittings have very small connection terminals and it is impossible to get all of these wires inside the fitting. You may need to have a separate junction box then just a single cable to the light fitting.
When replacing a socket outlet the physical position and relative orientation of the connections may be different. One may go Live-Earth-Neutral but the replacement may be Earth-Neutral-Live. Always double check the markings on the new accessory to ensure you have the correct polarity.
It is not uncommon for DIY persons to leave screw connection a bit loose. Loose connections can cause overheating and fires. Always ensure your new cables are tightly secured in all connections. Also beware of wires pulling free when removing the front cover of an accessory if the previous screws were left loose.
If hunting under the floor for a particular circuit cable always remember that central heating control wiring can be in the same cable type as used with lighting circuits. Do not mistake heating cables for other house circuits.
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