DEVICE FOR SUPERVISING A LEAKAGE CURRENT OF A LIGHTING ARRESTER

摘要

The invention relates to a device for supervising a leakage current of a lighting arrester (1) and to an measuring element (7) for detecting a leakage current in a leakage current circuit (3). A filter assembly (8) filters said leakage current in order to extract a third harmonic oscillation which is evaluated by an evaluation circuit (6) with respect to the quantity thereof. Said evaluation circuit (12, 24) delivers at least one warning signal to a display device (13, 14, 15, 25). In a preferred embodiment, three display devices (13, 14, 15) operating as a signalling light are provided. A power supply for the used circuits (5, 6) is obtainable by means of a transformer (16) which extracts a necessary auxiliary zero-potential energy contained in the leakage current and with the aid of a main power supply unit (19) connected to said transformer (16).