It can be applied in the electronic ballast of kinds of luorescent lamps and electronic energy-saving lamps. No necessity to modify the circuitry.I proper thermistor is parallelconnected on the two ends of resonant capacitor ot lamps,cold startup of electronic ballast and elec-tronic energy-saving lamps will urn into the Preheatstartup which can make the Preheatingtime reach 0.4-2S and extend the life of service to three times of the primary.