A normal mains 110/240V, 50/60Hz AC supply is increased by a special transformer to typically 7kV AC. This high voltage is carried by a shielded HV cable to the static eliminator, where it is connected to an array of emitter pins. This creates a high energy ion cloud, in which a very large number of positive and negative ions are generated. As the AC cycle changes, either positive or negative ions are produced in approximately equal quantities. A statically charged surface of either polarity passing close to this ion cloud will be quickly neutralised.