| 摘要 |
<p>An electronic ballast for a fluorescent lamp includes a lamp tube (1), a high frequency oscillator (2), a transformer (3), capacitors (C1, C2) and a starter (4), a pressure sensitive resistor (V) and a heat sensitive resistor(PTC). The ends of the starter (4) are connected respectively to the two filament cathodes of the lamp tube (1) and said pressure resistor (V) and heat sensitive resistor (PTC) are connected in series and are connected in parallel to the starter to the two filament cathodes of the lamp tube (1). When the voltage of a power supply drops by 8 % or more, the ignition of the lamp tube can be still started and furthermore, the on-off turning number of the lamp can reach up to 20,000 times so that the ballast according to the invention can effectively prevent the emergency fluorescent lamp from failure. <IMAGE></p> |
