Low-voltage garden lights are an inexpensive way to add lighting to a landscape. Low-voltage lights are attached to an electrical cable that is connected to a transformer, which is plugged into an exterior outlet. The transformer is needed to reduce the outlet voltage (120 volts) to 12 volts to safely operate the lights. You can buy a kit with all of the necessary equipment at your local hardware or home improvement store.
Measure the area where you want to install the lights. Lights for safety will typically illuminate down or out, while accent lights display lighting upward. Also measure the distance from the closest electrical outlet to where you want to place the first light. This distance needs to be included in the amount of cable you buy.
Draw a scale diagram of the area. Make 1 inch equal to 10 feet, or whatever per-inch equivalent will easily fit on paper. For example, if your house is 45 feet long, dividing that by 10 gives you 4 1/2 inches; round up to 5 inches for your diagram.
Draw an outline of the footprint of your house. If you want to hook up low-voltage garden lights on just one side, then just draw an outline of that side. Plan for safety lights at 10-foot intervals. Place small circles where you would like to add lighting and X’s at the location of electrical outlets.
Purchase a low-voltage lighting kit that meets your diagram requirements. The length of cable included in kits varies, so read the label carefully. Additional lights, transformers and cable can be purchased separately if necessary; however, do not exceed the voltage requirements of the transformer. For instance, up to 10 10-watt lights can handled by a 100-watt transformer.
Use a spade or lawn edger to cut a narrow trough for the cable. Read the manufacturer’s directions for the correct depth, which could range from 2 to 6 inches.
Set the transformer next to the electrical outlet. If the transformer includes a light sensor, make sure the transformer is not hidden behind bushes. You could place the sensor under a sheltered area, like a porch, if the location receives some sunlight (even indirect) all day. Avoid placing the sensor where it could register the light level as dark enough to turn the lights on during the day. Some low-voltage lights use a timer instead of a sensor, making placement of the transformer less important.
Attach the cable to the transformer, then start laying the cable on the ground next to the trough you dug. Lay the lights on the ground by the cable where you want to install them.
Hook up the low-voltage lights to the cable. The stake or base of the lights will either screw apart or slide apart, revealing a prong mechanism. Force the cable onto the prongs, then screw or slide on the light. The cable will be pierced by the prongs, which will touch the wire inside the cable.
Push the stake into the ground, tuck the cable into the trough and tamp down the cable with your foot. The area can then be covered with mulch if desired. Plug the transformer into the electrical outlet and set the timer, if applicable.