Principles of Buried Utility Detection

进行任何发掘将不可避免地使现场工作人员靠近地下公用事业（电力，天然气，电信，水）。应始终考虑在发掘过程之前和期间了解所有埋藏公用事业的确切位置。为了保护公用事业罢工，使用电缆定位器来检测埋藏公用事业的存在和接近。

When an alternating current (AC) travels along a cable, an electromagnetic field is generated. The alternating current not only creates a magnetic field but also the oscillation of the current between positive and negative creates a frequency known as Hertz (Hz). The electromagnetic field generated by an AC current, can be detected by a cable locator.