Mains powered circuit using an X2 Cap

[tvtech]

Hi all

I have built a LED lighting combined with 9V battery back up charging circuit using a 2.2 MF 305 V rated AC Cap. Driven directly from 220VAC.

All is going well. Circuit functions reliably and Nothing gets hot/warm.

Question is this: I don't quite understand Power Factor correction.......
Apparently, the 2.2MF cap will use only what it needs for supplying power to the LED's and charger and put the rest back into the Mains.....

I have clamped the output from the circuit to 16V. With a 16V shunt Zener rated @3W.

Testing current draw AC (Mains side) tells me it is using around 30W to power this simple circuit.

Anybody know where the losses are as the DC side uses around 2W Maximum.

Thank you
tvtech

 

[Diver300]

Measuring the current draw on an AC circuit does not tell you the power, it tells you the VA. If you use a power meter it will be much closer to the 2 W figure.

Capacitors store energy when they are charged. In your circuit the capacitor is charged one way each mains cycle, and discharged and charged the other way in the other half of the mains cycle.

The current you measured is mainly the current needed to charge and discharge the capacitor, as the energy is flowing in and out of the capacitor from the mains.

 

[tvtech]

Thanks Diver

I have spent around Two Months on this project.

Your input is much appreciated. And a Rep is due for you. Given. Thanks mate.

Regards,

tvtech