Patent ID: 6989759

Claim:
A lighting system comprising: at least one controllable first light connected to a first current supply; at least one controllable emergency current light, separate from said first light, and connected to an emergency current supply which is separate from said first current supply; control devices associated, respectively, with each said first light and with each said emergency current light, each of said control devices being connected to a common bus for the reception of control signals; a control signal module connected to said first current supply for monitoring current from said first current supply and for generating a monitoring signal corresponding to the monitored condition of said first current supply, said control signal module also being connected to said common bus for supplying said monitoring signal to said common bus for evaluation by at least one of said control devices, said at least one control device being constructed to activate said emergency current supply upon evaluation of a current supply disruption from said first current supply, wherein said control signal module is constructed and connected to supply additional control signals to said bus line for control and regulation of said first and said emergency current lights; and wherein said control device is constructed to recognize the transmission of said additional control signals in accordance with a predetermined characteristic thereof; and the control device of at least one of said emergency current lights also being constructed to effect an emergency current operation in response to interruption or failure of the monitoring signal, if the transmission of an additional control signal is not being effected.