| 摘要 |
A light controller for a discharge lamp (1) with an electronic ballast (2) is separate from the ballast, and is connected to control the mains voltage (4) supplied to the ballast. The controller has an output stage (5) connected in the mains voltage line and regulates the input power. A comparator (7) is connected to a control unit (6), the input of the comparator being provided with a control voltage (Uc) and a voltage depending on a phase angle controlled voltage (3). A device (9) regulates the control voltage (Uc) as well as a starting circuit (8) for switching on control voltage (Uc) in order to maintain constant the power taken up by the load despite mains voltage variations, the voltage depending on controlled voltage (3) is connected to comparator (7) through a circuit (10) simulating the electronic ballast (2). Initially, the starting circuit (8) supplies only a low voltage to the comparator (7). <IMAGE> |
