A device for avoiding switching-on current surges when switching on an inductive electrical power supply apparatus (2) has an AC switch (9), which is connected in series therewith, and a phase-gating circuit (19) by means of which the connection of the electrical power supply apparatus to the mains power supply AC voltage (3, 4) can be set from the switching-on moment (7) using unipolar phase sections of equal magnitude. Furthermore, a switching means (12) is provided for driving the phase-gating circuit (19). This switching means (12) allows a predetermined number of unipolar sections of equal magnitude to be produced. The oppositely polarised half cycle which then follows immediately in time is switched with a triggering (turn-on) signal of 170 to 180 DEG . In the phase-gating circuit (19), in each case one triggering signal is produced at the predetermined phase-gating angle in each of the half cycles following this half cycle. In consequence, irrespective of the remanence (which is produced by a preceding switching off operation) of the electrical power supply apparatus, dimming, for example, of low-voltage lighting systems (illumination systems) or the connection of a welding transformer is reliably ensured in a simple manner and using few electronic modules, without any switching-on surge currents occurring. IMAGE
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