A method for reducing IP level signaling and radio resource load during the attachment or update L3 of a mobile unit to a cellular wireless communication network is disclosed wherein access network elements and routing network elements are provided, an identification element is transmitted from the mobile unit to one of the access network elements. The DCAC inverter is operated in zero voltage switching mode, wherein the DC input voltage is used as the control variable for the lamp current IL, wherein fluctuations in the lamp current IL caused by the residual ripple of the DC input voltage are compensated by a variation in the switch-on times andor switch-off times of the switching elements QH, QL of the DCAC inverter. A special method to prepare the composition is provided. A power generation unit GU generates electric power using mechanical energy input by a pressing force of an output part 14 of the slide member 10.