Method of and device for determining a measure of the surface potential of a medium charged by means of a corona charging device

摘要

A medium to be charged is conveyed past a corona charging device, so that charge emitted by the corona charging device (2) is deposited on the medium surface (1).A measuring wire (4) is disposed between the medium (1) and the corona charging device (2), near the medium (1), which measuring wire (4) collects a part of the emitted charge.A first measuring circuit (11) determines a measure id of the charge current collected by the measuring wire (4). A second measuring cir­cuit (14) determines a measure if of that part of the emitted charge current that flows to the medium.In accordance with a predetermined relation a measure E of the sur­face potential is derived from these measures if and id.