POWER PACK

摘要

A mains power supply for supplying an electricity consumer connected directly or via a converter to an unstabilised direct current branch of the mains power supply, having a buffer capacitor which can be charged from the direct current branch and which also supplies the direct current branch for a predetermined minimum period of time in the event of a mains power failure or interruption in power, and wherein the buffer capacitor (C) is connected via a high impedance charge resistance (R) at the voltage (U1) of the direct current branch, a voltage limiting means (Dz) is connected in parallel with the buffer capacitor (C) and limits the voltage at the capacitor substantially to the minimum voltage (UM) of the direct current branch which is to be expected in the normal operation, wherein one diode (D) is connected in parallel with the charge resistance and serves to supply the electricity consumer from the buffer capacitor in the event that the input direct current voltage falls below the minimum voltage (UM).