Telecommunications system with 4-door intercom interface - has compact electronic module with mains supply plug inserted between door intercom and telecommunications interface

摘要

The telecommunications system (10) includes an 8-wire interface (110). Two-wires are used for connection (28,29) to the door intercom (16,17) which is adaptively coupled to the interface via an electronic module (18) that is powered via a mains supply plug (19). The interface is also connected to four doorbells (12-15). Pref. the housing of the electronic module contains a current source supplied from the mains and a switching stage for a number of doorbells. The module also contains an impedance converter and a signal evaluation device. The doorbells and the door opener (17) are supplied with a 12 V current supply, and the door intercom is supplied with a 48 V current supply.