filter capacitor question.

[Koolaide]

Trying to broaden my understanding of filter capacitors. How is it that a capacitor filters DC if capacitors do not pass DC?

Now my assumption is that the rectifier does not produce DC, but smoother AC if you will. Which will pass through a capacitor, with the remaining ripple is then smoothed by the filter capacitors.

All replies appreciated. Thanks Jim.

[wpaulvogel]

I’m going to do this simple. Think of the rectifier as a piston air compressor, every rotation it exhausts a pulse of air. The air tank the compressor is connected to is like the capacitor. With the air tank present tthere’s only a small pulsation felt from the compressor because of the reservoir the tank creates. The capacitor passes no dc in the power supply, it stores electric current. The larger the value capacitor the smoother the ripple. The larger capacitor is more stressful to the rectifier and power transformer though because it’s more difficult to fill the capacitor. Make sense?

[Koolaide]

got it thanks.