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Five-wire Unbalanced Feeder

Author: Edmund A. Laport

This type of feeder (Fig. 4.8) is characterized by a high Value of k with consequent reduction in earth-return current and over-all attenuation. The four grounded wires provide a high degree of shielding for the inner wire. The characteristic impedance is too high for some applications because of the single high-potential wire. Construction configurations for this type are discussed in conjunction with type XI.
Fig. 4.8

This quincunx-section feeder has wide application possibilities for low-frequency and medium-frequency power transmission where low attenuation and moderate value of characteristic impedance are desired. When h >> a,


When ρ1 = ρ2,


An example of a set of values is:

p (inches) h (inches) a (inches) k Z0 (ohms)
0.064 120 10 -0.775 345

Last Update: 2011-03-19