| 摘要 |
An emergency lighting unit comprises a battery-powered converter circuit for maintaining a discharge in a gas discharge or fluorescent light, the converter circuit also being arranged to generate a high voltage for striking the discharge in the light. When the mains supply is good and a switch is closed for turning on the light, the converter circuit is activated to provide its high voltage for striking the discharge, after which the discharge is maintained from the mains supply. If the mains should then fail, the converter circuit provides its low voltage from its battery to maintain the discharge. If the mains fails while the light is switched off, the converter circuit strikes and then maintains the discharge in the light.
|
