A locator for locating a concealed conductor carrying an alternating current having a first and second frequency

摘要

A locator for locating a concealed current carrying conductor is described. The conductor carries an alternating current having at least a first frequency and a second frequency, wherein the alternating current is produced by at least one dedicated signal generator coupled to the conductor. The locator comprises: at least one magnetic field sensor 3, 5 operable to convert electromagnetic radiation from the conductor into a field strength signal; a digital analogue converter (CODEC 11) configured to generate a digitised signal dependent upon the field strength signals from the magnetic field sensor; a digital signal processor 16 configured to isolate components of the digitised signal resulting from the first frequency and the second frequency; and process the isolated components to generate one or more signals indicative of the proximity of the conductor to the detector; and an output configured to generate an audio and/or visual indication of the proximity of the conductor, wherein in some aspects the isolated signal components resulting from the first frequency signal and the second frequency signal are contemporaneously processed. Other aspects relate to the method of using the locator and to a carrier medium carrying instructions to execute said method using a computer