Low voltage garden lighting

The majority of modern garden lighting works at 12 or 24volts. To be able to operate these lights at 12 or 24 volts you will require a driver or transformer. These devices alter the voltage usually from 230 volts to 12 or 24volts. There is a very good reason for this reduction and that is safety. If the cable running to the light is damaged it will not harm anyone because the voltage is so low. However, if the cable were 230 volts and it became damaged it could quite easily kill someone (if an *RCD is not working properly or fitted).

*RCD is a Residual Current Device is a life-saving device which is designed to prevent you from getting a fatal electric shock if you touch something live, such as a bare wire.

Low voltage garden lighting still requires 230 volts (up until the transformer/driver) and this is fed by using steel wired armoured cable. This should be buried below the ground (regulation of 500mm/18 inches) and covered with a yellow warning tape. However due to the low voltage cable being 'safe', the cable can be covered with mulch or left just below the soil surface.

Depending on how many lights you are trying to illuminate will determine the size of the transformer. However, low voltage cable may reduce in voltage if the amount of lights fitted extends over a long distance (see voltage drop chart below) It is preferable to keep the number of lights used to a minimum, otherwise this will result in a voltage drop and the lights will become dim.

It is important to note that although these lights are low voltage, the halogen fittings can still become hot. This will depend on the wattage of the lamp used i.e. 50 watt will be hotter than a 20watt lamp. The material used for the fitting will also make a difference to the overall heat eg a stainless steel fitting will retain its heat for longer than a aluminium fitting. With any lighting it is advisable to be sensible when changing lamps or moving the fittings. Always wear gloves to change the lamp or when re-positioning the unit if it has been on for some time.

However, LED's create very little heat and are often warm to touch. Please note that if in doubt please do not touch any bulb/fitting if they have been switched on.

An approved quality light fitting should always carry an IP rating (as below). This indicates how well it will stand up to external conditions.

The installation of external lighting should be carried-out by a professional who knows the correct procedures and uses equipment that will keep it safe.

Voltage drop chart