| 摘要 |
<p>A ballast (100) for driving one or more lamps (121) includes a controller (111) and a current reduction circuit (140) for accelerating a controller reset. Upon detecting a fault, the controller (111) disables the ballast for a preset period of time, and resets. The controller (111) additionally resets when the ratio of a supplied second value to a supplied first value falls below a threshold value. The current reduction circuit (140) reduces the supplied second value in less than the preset period of time, such that the ratio falls below the threshold value and the controller resets. An emergency lighting system (201) includes the ballast (100) as a primary ballast (100), a backup ballast (200), and a primary power source (102). The controller (111) detects a fault if the primary power source de-energizes and the backup ballast (200) disconnects the one or more lamps (121) from the primary ballast (100). The current reduction circuit (140) accelerates the reset of the controller (111) when the primary power source (102) de-energizes.</p> |
