Centrally controlled lighting installation for public buildings - has switches for individual lights allowing their operation independently of central switch

摘要

The lighting installation includes a normally-closed central switch (2) which can be opened against the action of a spring, to break the circuit to the lights (3,5,7). A first individual light switch (4) for the light (3) can be operated locally by an operating lever (12) in addition to being operable by attraction of a lever arm (11) by an electromagnet (11). If the central switch is opened briefly, the interruption of the magnetic field of the electromagnet causes the switch (4) to open due to gravitational force on the arm (11). Once the central switch is closed again, the switch contact (10) is opened so the switch (4) does not close again unless the lever (12) is used to close the contact (10). On the other hand, the switch (4) can be opened, even if the central switch is closed, by operating the operating lever (12) to pivot the arm (11) away from the electromagnet. A second individual switch (6) for lights (5) acts similarly to the first but uses an external lever arm (15) and a spring-urged normally-closed switch element (17) connected in series with the electromagnet (14).