Patent ID: 8896977

Claim:
A method for operating an electrical power supply network, the power supply network including a plurality of levels with different voltages, the levels being connected via switches, a first of the switches being embodied such that a maximum interruptible short-circuit current of the first switch is relatively smaller than a maximum flowing short-circuit current, the method comprising: carrying out a test, in a case of a failure, to determine whether the short-circuit current presently flowing through the first switch is relatively smaller than the maximum interruptible short-circuit current; and maintaining the first switch in the closed position upon determining, from the test, that the short-circuit current presently flowing through the first switch is not relatively smaller than the maximum interruptible short-circuit current; and opening the first switch to an open position upon determining, from the test, that the short-circuit current presently flowing through the first switch is relatively smaller than the maximum interruptible short-circuit current.