Basic Rules for Outdoor Lighting Installations
When installing outdoor lighting, the major rule is Safety First. Here are some rules that will help insure your safety during the installation process and the safety of everyone once the lighting is in place.
1. Check Local Codes - Your municipality will have codes and requirements about what sort of cabling may be laid down, how much of a load you can put on your system, and other basics. Find out what these codes are and follow them carefully.
2. Turn Off the Juice! - Before you attempt any wiring or transformer installation, turn off electrical current at the main switch
3. Use a Ground Fault Interrupter (GFI) - Many local codes require outdoor circuits to be protected with a GFI. Even if your codes don't, it's still a good idea. The GFI will detect an abnormal diversion of current (such as when a person or pet has come into contact with the "hot" wire and is being shocked) and will turn the current off.
4. Ground Everything - Cable that's installed underground needs to contain a grounding conductor. Make sure that all fixtures are properly grounded as well.
5. Use Approved Materials - If you're wiring underground, use UF cable connected to a fuse or breaker. Use fixtures that have an Underwriter's Laboratory (UL) seal of approval.
6. Use Weatherproof Equipment - Not all cabling, transformers, and fixtures are rated for outdoor use. Make sure the ones you choose are.
7. Bury Your Cable - If you're using line voltage (124v), you need to bury the cable at least 18 inches deep. 24 inches is even better. You're less likely to hit the cable with a shovel or spading fork. And you're less likely to find it dug up by wild animals or your own dog.
8. Protect Your Cable - Burying your cable may be enough protection for most of its length. But where it's exposed above ground, run it through conduit to protect it from the elements and you from it. Even below ground, where it makes bends, use conduit to keep the cable in place without breaking. Some local codes may even require you to run the entire cable through conduit. If you followed tip number 1 above, you'll know whether your local codes are among them.