In low voltage systems, the mains voltage is reduced through a transformer to 12 volts, which is a very safe voltage incapable of providing fatal shock and therefore allows the use of flexible cables around the garden, rather than the fixed cabling required for mains voltage systems.
For many years, creative garden lighting has been dominated by the MR16 low voltage halogen lamp. This 50mm (2 inch) diameter lamp features a miniature halogen capsule lamp mounted in a multi-mirror reflector to provide a precisely controlled beam of light with little peripheral light spill. These lamps run on 12 volts, so although this requires the installation of transformers to step the voltage down, it also permits very flexible low voltage wiring configurations and the ability to adjust the lighting easily because 12 volts is so safe. It is twice as energy efficient as old-fashioned Par 38 tungsten lamps and the “dichroic” multi-mirror reflector reflects all the light forward while allowing much of the heat to dissipate through the rear of the lamp; in other words, you are projecting much less heat towards your planting or down onto the dining table. MR16 lamps are available in a wide choice of wattages from 10 to 50 watts and beam angles from 12 to 60 degrees, which gives the designer much more choice in accurately and precisely lighting subjects without glare. For designers of garden lights, the appeal of such a wide range of lamp choice is reinforced by its small size: it is less than half the diameter of a PAR38 lamp and about one-tenth of its overall size. The result is garden spotlights which can be much smaller and yet produce more light, with greater versatility, than old-fashioned tungsten fittings. The majority of directional spotlights supplied by Lighting for Gardens are 12v halogen spotlights, uplights and downlights, ranging from the rustic E4171N rustic brown powder-coat spike spotlights to the modern Elipta Compact wall spotlight range.
Some smaller MR11 12 volt lamps are also available for lower wattage applications where a miniature fitting is required, such as Elipta Microspots. 12 volt spreadlights and some steplights typically use a halogen capsule lamp without a reflector to diffuse light in all directions.
Most garden retail outlets offer garden lighting kits usually including light fittings made from plastic to reduce cost and featuring easy assembly, requiring few tools and little electrical knowledge. They usually feature a ribbed cable to which lights are attached by clamp-on connectors, in which sharp contacts pierce the insulation to make contact with the conducting wires inside, a form of connection which is prone to degradation and electrical arcing over time. The low voltage cable connects to a transformer which is often designed only for interior use. The limiting factor is the material the lights are made from, usually moulded plastic. Most such plastics will deform in close proximity to heat, so the lamps used in these fittings tend to be relatively low power, often 10 watts or less. Lighting for Gardens doesn’t supply such cheap plastic kits as they typically combine poor performance and short lifetime. We supply only metal light fittings which can accommodate the heat produced by lamps capable of providing professional lighting effects, and all our transformers are weatherproof for exterior use.