Gardening Articles: Care :: Plant Care Techniques
Light Up Your Landscape (page 3 of 4)
by Beth Marie Renaud
Low-voltage lighting -- transformer, fixtures, and cable -- is relatively safe to install yourself. However, it can be hazardous if the connections at the fixtures are loose or if too many fixtures are connected on one cable. Most equipment comes with detailed instructions for installation, but here are some important things to keep in mind.
Before you install any lighting, check local electrical codes. For instance, some areas allow weather-rated low-voltage flexible cable when installing fixtures in trees, while others insist on metal-clad cable.
Be sure to follow instructions that come with the fixtures, and check with the seller or manufacturer if you have questions. If you are unfamiliar with wiring, you may want to have an electrician do the installation, or check your work.
The transformer converts standard 120-volt household current to 12 volts. Check its wattage capability; most can operate systems using up to several hundred watts. Because there's a limit on the number of fixtures a transformer can power and on the distance the cable can run -- about 100 feet -- without significant loss of power, divide the lighting load into several circuits of 6 to 10 lights each. The size of bulbs and transformer are also important; consult manufacturer's specifications and stay within required limits. A basic transformer capable of handling 6 12-watt lights can cost as little as $30. One that can support 10 50-watt lights will cost anywhere from $130 to $350, depending on whether it is electronic or magnetic. To keep the lengths of cable at a minimum, place the transformer where it's central to the fixtures.
Mount the transformer next to an outside outlet, but don't plug it in until you have mounted the fixtures and laid the cable. To add a time clock, plug the transformer into the clock box's receptacle and then plug the clock into the outlet.
Place the fixtures where you want them. Attach one end of the cable to the terminal on the transformer, then connect the fixtures. Some fixtures have a clamp you lay the cable into; other types require that you cut the cable and connect it to the fixture's wiring. Consult manufacturer's instructions.
At this point, turn on the system at night and, if needed, adjust the lights for placement and patterns. The cable can run on the soil surface if plants or mulch will cover it. Or bury it in a narrow trench, taking care not to place it where you might slice it with a shovel. If you have pets that might dig it up, bury the cable about 12 inches deep; otherwise, 6 inches is sufficient.
Once installed, low-voltage systems require relatively little attention, though some routine maintenance will ensure a longer life. To avoid corrosion, remove the lamps once a year and coat the sockets with a silicone-based lubricant. Clean debris out of fixtures, particularly uplighting ones, regularly. Replace dead lamps immediately; otherwise unused voltage will go to the other lamps and cause them to burn out faster. Lastly, prune vegetation around fixtures to maximize light output. The exception to this may be with tree-mounted fixtures; small branches growing in front of these lights helps to diffuse their bright light and casts intriguing shadows on the ground.