Emergency operation arrangement of ISDN communications assembly group

摘要

The arrangement is part of an ISDN communications assembly group comprising a switching regulator, and supplied by an So conductor, as well as an additional 24 Volt supply of a local network connection instrument. An emergency operation detection arrangement with a detection- and control circuit is provided for a genuine emergency operation at loss of the local network connection. The emergency operation detection arrangement comprises preferably an So voltage detector and an So conductor sensor, as well as a line logic comprises for normal-/emergency operation.