Hi Good morning to group member.Can any member help me. I brough a hobby kit to build a 20 watts flourescent light by car battery, it turn on the light immediately when power is connected. But compared to those energy saving light bulbs(actually is also with flourescent tube inside the bulb)it only turn on slowly when power is connected.I don't understand what is the different as both also driven by electronic circuits,won't you thing the hobby kit is simple & efficiency to turn the flourescent on ? thanks in advance. Best Regards Hoong
You've built an inverter circuit. This sort of circuit makes 200 volts or higher / some kHz AC from 12V DC. Those voltage and freq can light fluorescent light directly. Energy saving light bulb has inverter circuit in it. That makes those volt./freq. from 100-220V / 50-60Hz AC. Then using energy saving bulb with your circuit is abnormal. It causes damage both of bulb and your circuit. Good Luck
Using higher freq. than 50/60Hz is needed not for lighting, but for preventing flicker. Flicker is not good for your eyes. This is the purpose of the inverter fluorescent light. And higher freq. reduces the size of transformer in the inverter circuit. Fluorescent tube can be lit even by DC if supplying voltage is high enough. (Actually lighting by DC may cause some problem, but I'm not sure in it.)
Fluorescent tube is a sort of discharge tube. It's not a conductive device then it doesn't go with Ohm's law. When the supplying voltage is lower than a voltage, (discharge voltage) the load current is ZERO. Increase voltage over discharge voltage, increase load current drastically. (and bomb!) Inverter circuit for fluorescent tube develops some hundreds volts when it's not connected to the tube. (voltage without load) When it's connected to the tube and load current flows, the inverter circuit drops the output voltage. Then, if your inverter circuit has enough power, your fluorescent tube lights brightest within the safety condition, I think...
Any way, once the discharge current flows, the discharge voltage is decreased, so the actual relation of load current and voltage is much complex than my description. I don't know the exact value of discharge voltage of fluorescent tube.
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.