For simplicity sake we will assume we need 200 ft of wire to complete our installation. Wire generally comes in 100, 250 and 500 ft rolls, and since the wire will be cut at each light and junction you don't need to worry about continuous run length for the roll. Also, as you did when calculating the size of your power source, you should also be conservative with the amount of wire you will need and account for an additional 10-15% over your calculated needs. For our sample system we will assume we need 250 ft of wire.
3. Wiring Your Landscape Lighting System and Fixtures - Since we are solely focused on Low Voltage LED Landscape Lighting in our DIY tutorial, we will only be focused on Low Voltage systems for the wiring illustrations. There are a few unique characteristics of low voltage wiring systems that differentiate from standard 120V household wiring. Generally speaking there is no polarity in the majority of Low Voltage Landscape Lighting fixtures, so unlike installing a new light fixutre at home there is no difference between the wires (no black and white to keep track of), and there is also no ground wire on the fixtures.
Generally most Landscape Lighting fixtures are installed in daisy chain format with fixtures being installed from one light to another down the line. It's also common for light to installed in groups by creating a T intersection at some point in the system.
The illustration below shows a typical wiring configuration for a Landscape Lighting system followed by detailed illustrations of the wiring methods.
As you can see we've highlighted three areas that we will illustrate in more detail below.
A) Wiring of a Single Landscape Lighting Fixture in a series of lights.
When installing a Low Voltage Landscape Lighting fixture inline you generally will have three wire ends to connect together for each conductor (one from the fixture, one from the power source and one to the next fixture). As we mentioned previously with Low Voltage Lighting either conductor can be used (there is no black and white to worry about).
B) Creating a "T" Junction for Wiring a Landscape Lighting System.
There will often be instances in a Landscape Lighting System where it's not possible or practical to have all fixtures installed inline where a T Junction is necessary. In our sample system a good example of this would be the stair area. As with wiring a fixture inline the main power wire is cut and the three conductors are connected together with silicone filled wire nut.
C) Fixtures installed at the end of the Landscape Lighting System.
Lastly we have fixture that will be installed at the end of the line or wire. Fixtures at the end of your system will just have connections from the fixture to the end of the wire using a silicone filled connector nut.
We have now covered the basics for installing a Landscape Lighting System and will now put together a sample order for the sytem we've created.