Consider using conduit when burying electrical cables
Tim Carter of our driveway no longer turned on. I checked, and the circuit breaker had tripped. I went to reset the breaker and it immediately popped, indicating a dead short in the circuit. Dead shorts are bad.
Although I’m not a master electrician, I have done lots of residential wiring to code, and I knew how to quickly isolate the sections of the circuit to determine the location of the short. Within minutes, I discovered the short was in a section of wire that was buried between the corner of the garage and an oak tree where an aboveground junction box was located.
As it turned out, the short was at the end of a single piece of PVC conduit that the builder, or his electrician, had placed under our blacktop driveway. No conduit was used anywhere else, just under the driveway. The wire exited one end of the conduit and made a sharp turn. The up-and-down movement of the frost action here in New Hampshire had rubbed the plastic insulation off the cable where it contacted the sharp edge of the PVC conduit.
Sharp rocks are brought to the surface slowly by frost action. They can cut into unprotected wire and cable even though it is rated for direct burial. Garden spades, shovels and deepcutting tillers can chop into unprotected cables. Conduit prevents damage from almost all of these accidents.
Those who live in warmer climates where soil frost isn’t an issue should always bury cables in conduit as well. Code-approved PVC conduit is affordable. It’s easy to install and comes with pre-bent fittings, allowing you to go around tighter corners.
Should you decide to use conduit around your home, always take photos of where it is before you cover the conduit with soil. If your digital photos are stored online, create a public album and place the URL to it on a piece of paper that you put in a zip-lock sandwich bag next to your circuit breaker panel. Mark on it: PHOTOS of BURIED EXTERIOR CONDUIT
Believe me, a future homeowner, contractor, or electrician will thank you.
Another key point is to follow the National Electric Code with respect to all provisions dealing with conduit and the required depth of burial. Even though you bury the cables the recommended depth, they can be damaged by an inexperienced equipment operator. The key, in my opinion, is to have a clear record of exactly where all underground cables are buried on your land.
Tim Carter writes for the Tribune Content Agency. You can visit his website (www. askthebuilder.com) for videos and more information on home projects.