Abstract: A device for locating faults on the lines of electrical power distribution systems, including generally a variable impedance means adapted for connection in series with an electrical power line, and means for switching such variable impedance means between a first low impedance value when an initial current I.sub.1 of predetermined level flows on the power line for a predetermined period of time to enable detection of a fault condition, and a second high impedance value which limits the flow of current to a low level I.sub.2. A meter or other indicating device provides a reading of the current I.sub.1 to determine if a fault condition exists. In this fashion, the fault locator device limits both the magnitude and the time duration of the current when testing for a fault, so as not to adversely effect any system components.