A contact element for a power switch which, in order to open or close the switch, cooperates with an opposite element, with a transitory rotating electric arc forming between the contact element and the opposite element when the switch is operated. The contact element has an electrode part which includes a portion made of an electrically conductive material. This portion defines a contact surface, with the electrode part having a defined width and being curved in the direction of the width to have the form of an open loop having a connecting end and a free end. A current may be introduced approximately tangentially to the open loop at its connecting end, and the free end is spaced from the connecting end in the direction toward the interior of the loop by a distance which is less than the defined width.