Abstract: Methods for controlling a voltage present at an electric fan during a startup of the fan are disclosed herein. The fan serves to generate a flow of air for cooling a device. The method includes applying an output voltage of a power supply, which serves to supply voltage to the device, to the fan; and switching on and switching off the output voltage of the power supply applied to the fan by a switch pulse-width-modulated-controlled by a control unit so that the Root Mean Square value of the current flowing through the fan is less than a startup current of the fan.

Abstract: Methods for controlling a voltage present at an electric fan during a startup of the fan are disclosed herein. The fan serves to generate a flow of air for cooling a device. The method includes applying an output voltage of a power supply, which serves to supply voltage to the device, to the fan; and switching on and switching off the output voltage of the power supply applied to the fan by a switch pulse-width-modulated-controlled by a control unit so that the Root Mean Square value of the current flowing through the fan is less than a startup current of the fan.

Abstract: The disclosure relates to a current-measuring apparatus having an assembly with two or more burdens in series connection and a current transformer module with a secondary coil. Herein, the series connection includes three or more contacts so that the connection combinations of the secondary coil to in each case two of the three or more contacts enables different groups of one or more burdens to be switched with the secondary coil to form an electric circuit. A secondary current induced by a primary current to be measured in the secondary coil is able to flow through the electric circuit formed in this way.