If you’re looking for an outdoor project this summer that can add safety and security while making your landscaping really pop, look no further than low-voltage outdoor lighting. Installing outdoor lights is fun, easy and affordable. It can make pathways safer to negotiate, and turn any backyard into a welcoming evening oasis.
What you’ll need
There are three basic components to any exterior low-voltage lighting system: the lights, the transformer and the cable. It’s important that all three be selected to work together.
At the heart of the system is the transformer, also sometimes called a power pack. The transformer is housed in a weatherproof metal box, and converts incoming 120-volt AC electrical current down to 12 volts AC. The transformer also typically contains a timer or a photo cell, which is used to control the on/off cycles of the lights.
Transformers are rated in watts of output, which is the total number of watts of lighting that they’re capable of handling. This is a very important number to know, because it’s going to tell you how many lights of what type you can install on your system.
There are thousands of different low-voltage lights to choose from, which utilize halogen bulbs with wattage ratings from 4 up to 50 watts. There are spot lights, hanging lights, mushroom lights, deck lights that can be built into steps and decks, and even waterproof lights for use around ponds and fountains. You also have a wide choice of styles and materials.
Connecting it all together is the cable. Low-voltage lighting cable is made from stranded copper wire, protected on the outside with a heavy insulation that’s weather-resistant and approved for direct burial. Once again, you want to select the wire based on the wattage of lighting you’ll be installing, and the length of wiring run. Low-voltage wire is available in 16, 14 and 12 gauges.
You can purchase everything you need as a kit, with a set of lights, a transformer and a coil of wire. The good thing about doing it this way is that you’re ensured that everything is matched, and you don’t have to do any calculations. But you’re typically going to be limited to just those lights on that transformer, and you won’t be able to add any more later on.
A better way to go is to first design a lighting layout for your yard, based on what you currently need. Look at some examples of lights, see what you think you’d like to put where, and make a note of the different wattages. Add everything up, then factor in a certain percentage to allow for future expansion of your system. That will tell you how big of a transformer you need to meet your current and projected future needs.
For example, perhaps you do a layout for your backyard that includes 10 15-watt lights, as well as two 40-watt spotlights for a couple of larger trees. That’s a total of 230 watts. You have some ideas for expanding your landscaping later, so you want to factor in an additional 25 percent, or about 58 watts. The total is 288 watts, so you’d want to select whatever transformer is the next size up from that, such as 300 watts.
The same thing would hold true for the cable. Based on your layout, you know where the lights will be installed, so you can measure how much cable you need. By knowing the length of the cable and the number of watts, you can select the appropriate cable to fit the system.
Installing the system
Now comes the fun part! You can have your system up and running in just a couple of hours, with no special skills and only some basic tools.
First, select a spot for the transformer. Transformers don’t have very long electrical cords, so it will have to be close to a GFCI-protected (ground-fault circuit interrupter) outlet. If you’re installing it outside, be sure to use a protective cover over the plug and outlet to protect them.
The cable is attached to the bottom of the transformer. There are two screws, and it’s simply a matter of stripping the insulation off the cable to expose the wire, and attaching it to the screws; complete instructions will be included with the transformer. From the transformer, you can begin laying out the wire in the general direction of where your lights will go, but don’t hook anything up yet.
Next, assemble your lights. Depending on the type and style of light, you may have to install the bulb, attach a stake or do some other type of assembly. Carefully follow whatever instructions came with the light fixture. Also, when handling halogen bulbs use a cloth. The bulbs are sensitive to oils from your fingers, and that can greatly shorten the bulb’s life.
Now place the lights where you want them, before you finish running the cable. Check your layout, and rearrange things as needed. When you’re happy with everything, finish laying out the cable on the ground so that it follows the shortest route from light to light.
Connecting the lights to the cable is simply a matter of pinching the light’s connector onto the cable. Place one-half of the connector on each side of the cable, and align the connector’s arms into the appropriate slots. The connector has two metal prongs that will penetrate the insulation and make contact with the wire inside. Simply squeeze the halves together until you have as tight a connection between them as possible.
Using a pointed shovel, dig a 6-inch-deep trench next to the cable. Place the cable in the trench, but don’t bury it yet. Plug the transformer in, activate the timer or cover the photocell if necessary, and check each light to be sure it’s working. If everything’s OK, bury the cable and you’re all done!