Underground Power Cable Faults

Underground power distribution is now common in most upscale communities. There are many advantages, including elimination of unsightly power poles and aerial wires, elimination of damage from falling trees and tree limbs, elimination of automobile/pole conflicts, elimination of snow and ice damage, elimination of wind damage, and of special importance to radio amateurs, elimination of power line antenna pattern distortions and greatly reduced RF interference radiation. However, underground power distribution is not without problems. One of the biggest problems is finding underground cable faults. A relatively new solution to that problem is to bundle a fiber optic cable with buried power lines. Hot spots along a power cable deform the fiber optic cable, causing a light-wavelength impedance bump. Short light pulses transmitted down the fiber reflect back from any impedance bumps. Echo times can be measured with sufficient accuracy to pinpoint hot-spot locations to within about three feet (one meter) of cable length. ©2005 Tigertek, Inc. All rights reserved.

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