3-10 Since the output waveform is essentially a sine wave with both alternations at the same polarity, the average current or voltage is 63.7 percent (or .637) of the peak current or voltage. As an equation: E_{avg}(the average load voltage) = .637 × E_{max}Where E_{max}= The peak value of the load voltage pulse And I_{avg}(the average load current) = .637 × I_{max}Where: I_{max}= The peak value of the load current pulse Example: The total voltage across the high-voltage secondary of a transformer used to supply a full-wave rectifier is 600 volts. Find the average load voltage. (Ignore the drop across the rectifier tube.) Solution: Since the total secondary voltage is 600 volts, each diode is supplied one-half of this value, or 300 volts. As the secondary voltage is an rms value, the peak load voltage is: E_{max}= 1.414 × E_{s}E_{max}= 1.414 × 300 E_{max}= 424 volts The average load voltage is: E_{avg}= .637 × E_{max}E_{avg}= .637 × 424 E_{avg}= 270 volts NOTE: If you have problems with this equation, review NEETS, module 2, pertaining to this area. As you may recall from your past studies in electricity, there are advantages and disadvantages in every circuit. The full-wave rectifier is no exception. In studying the full-wave rectifier, you have found that when the output frequency is doubled, the average voltage is also doubled, and the resulting signal is much easier to filter because of the high-ripple frequency. The only disadvantage is that the peak voltage in a full-wave rectifier is only half the peak voltage in a half-wave rectifier. This is because the secondary of the power transformer in a full-wave rectifier is center tapped; therefore only half the source voltage goes to each diode. Fortunately, there is a rectifier that produces the same peak voltage as a half-wave rectifier and the same ripple frequency as a full-wave rectifier. This circuit, called the BRIDGE RECTIFIER, will be the chapter of our next discussion. Q12. What is the ripple frequency of a full-wave rectifier with an input frequency of 60 Hz?