Having a little trouble figuring out where I screwed up in a calculation. I have an under the counter light that comes with three 12 VAC halogen puck lights. The power supply is also a dimmer. The power supply converts 110 VAC to 12 VAC and has three levels of brightness. I was wanting to change the lights to LEDs, so I and purchased a bridge rectifier, but wanted to calculate the filtering cap for it. Everywhere I checked, says to use between a 1000 - 2000 uF cap. The calculations I found here give the formula:

**Smoothing capacitor for 10% ripple, C = (5 × Io) / (Vs × f)**

C = smoothing capacitance in farads (F)

Io = output current from the supply in amps (A)

Vs = supply voltage in volts (V), this is the peak value of the unsmoothed DC

f = frequency of the AC supply in hertz (Hz), 50Hz in the UK

Using this formula, I insert my numbers. I get .03472 F. That's 34720 uF! Did I mess something up? That's much higher than the 1000 - 2000 uF everywhere else recommends.

The power supply says it puts out 12 VAC and 60 watts MAX. 60 watts at 12 volts is 5 A max. 12 volts at 60 hertz and the formula shows 25/720 = .03472 F. Can someone tell me what went wrong? Thanks in advance.

Tony