Zones selective locking (zsi -) power distribution systems and method for operating a zsi - power distribution system forms

摘要

There are power distribution systems (100) and method. In one exemplary embodiment, a method is described, so that by means of a first circuit protection device in a zones selective locking (zsi -) the system (100) to determine whether a blocking signal to a second circuit protection device in the zsi - a system (100) is to be output. The method comprises the detection of a rate of change of the first circuit current flowing protection device by means of a current change rates sensor (112). A switching unit (110) receives the current change rates signal from the current change rates sensor (112). The current change rates signal is proportional to the detected rate of change of the protection device by the first circuit current flowing. The switching unit (110) determines whether a blocking signal to the second circuit protection device are to be output, based, at least in part, on the current change rates signal.