| 摘要 |
A lighting control includes a primary and a secondary input power connection for connection to a primary (mains) and a secondary (battery) power supply respectively, control circuitry for controlling delivery of power from the input power connections to one or more light sources, sensing circuitry configured to sense an external impedance coupled, in use, to the primary input power connection and a controller for determining a present operating state of the one or more light sources. The controller includes a latching module adapted to maintain a state information indicating the present operating state of the one or more light sources. The control circuitry is operable to control delivery of power to the one or more light sources in dependence upon the sensed impedance measure and the determined operating state. The lighting devices may be installed in a conventional lighting circuit that uses momentary toggle switches. |
