# Re: how to calculate the Vo(dc) of a fullwave bridge rectifier with n smoothing capacitor? and also how to find the smoothing capacitor value?

Home Electrical Engineering Forum General Discussion how to calculate the Vo(dc) of a fullwave bridge rectifier with n smoothing capacitor? and also how to find the smoothing capacitor value? Re: how to calculate the Vo(dc) of a fullwave bridge rectifier with n smoothing capacitor? and also how to find the smoothing capacitor value?

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 Tip: It is possible to build your power supply without adding a regulator, when you want to power up an electrical motor, a small ripple in voltage will not affect the performance, unlike the electronic circuits and devices!

Designing of +12v 5A Power Supply:

To calculate the voltage required and the transformer secondary winding we first determine the input voltage for the regulator, which is 15v, plus a 10% of this value for ripple. For a regular transformer we have to consider a bridge rectifier, as a result; we will add 1.4v. So the secondary winding should be 15+1.5+1.4=18.9 lets say 18v @ 5 Amps. Now we will calculate the capacity of the filtering capacitor. By using equation number 1 and assuming that f=60Hz, we will get C=5 x 5 / ((18-1.4) x f) =25,100µF