All about Compact Fluorescent Lamp circuit (CFL):
The CFL is also known as compact fluorescent light, energy saving light, and compact fluorescent tube. Fig 1 shows the CFL lamp.
CFL is compact and energy efficient lamp. It requires less amount of power i.e. 13 to 14 watts than Incandescent light so it is widely used to save energy. Lifespan of CFL lamps is 7 to 9 years.
Working of CFL:
Fig 2 shows the diagram of CFL lamp circuit and the parts of CFL.
The main three parts of CFL lamp is Base, circuit, and tube. We apply actual AC supply to the base.
A CFL uses vacuum pipe which is same as tube light. Tube has two electrodes on both ends and they are treated with Barium.
Cathode is having temperature of 9000C. When we apply AC supply to the cathode it generates a beam of electrode. The beam is further accelerated by potential difference between electrodes.
From fig 3 we can see that, accelerated electrons strike mercury and organ atoms, and as a result it produces low temperature plasma. This process initiates the radiation of mercury in ultraviolet form.
Inside the tube “Luminophore” is present which is used to convert ultra violet light into visible light.
The CFL also consist of switch mode converter and it works on very high frequency. It is replacement of ballast (choke) and starter assembly.
Circuit explanation of CFL:
When AC supply applies to the circuit then it first converted it into DC by using rectifier.
Then convert DC into high frequency AC using transistors. The resulting high frequency is applied to the lamp tube.
Key component of PCB of CFL:
Bridge rectifier made up of diode 1N-4007
Faults of CFL:
Capacitor bulging due to excess heat.
Heat shrink around coil failed.
Sometimes diode doesn’t work properly then either brightness becomes less or lamp blinks continuously.
If lamp get more time to turn on that means there is problem of filter capacitor.
If there is switching problem then we need to change transistors.