METHOD FOR SECURE CONNECTION OF AN EXTERNAL POWER SUPPLY TO AN OPERATING POWER SUPPLY AND CIRCUIT LAYOUT FOR CARRYING OUT SAID METHOD

摘要

The invention relates to a method for secure connection of an external power supply to an operating power supply, in particular on a vehicle. A switch unit (SE) is arranged between the operating power supply (BN) and a terminal clamp (VK). The switch unit (SE) is connected to a controller (SG) and the terminal clamp (VK) arranged for connection to the external power supply (FN). Said method comprises creating a pulsed voltage at the terminal clamp (VK), at least when the switch is open; making measurements of the voltage from the external power supply at the terminal clamp of the (VK) during the pulse pauses; comparing measured values with the voltage(s) of the operating power supply (BN) and controlling the switching unit (SE) on the basis of the results of the comparison. The invention also relates to a circuit for carrying out said method.