Аннотация:The electrostatic potential difference between the bulk and the edge of a two dimensional electron system (2DES) shows a strong hysteresis in the integer quantum Hall regime. Fabricated at different positions on Hall bars, single electron transistors (SETs) were used as local potential probes. They allow us to distinguish between bulk- and edge-effects. Edge-SETs were placed at a distance of 1 μm to an additional sidegate which provides the possibility of shifting the edge depletion region under the SET. In this case the hysteretic signal which is associated with the Hall voltage of induced eddy cut-rents is suppressed.