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Typically, the design engineer requiring the use of Litz knows the operating frequency and RMS current required for his application. Since the primary benefit of a Litz conductor is the reduction of AC losses, the first consideration in any Litz design is the operating frequency. The operating frequency not only influences the actual Litz construction, it also determines the individual wire gauge.
Ratios of alternating current resistance to direct current resistance for an insulated solid round wire (S) in terms of a value (X) are shown below:
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