Measurement of Resistance and Reactance of Expanded ACSR [includes discussion]

A convenient method for the measurement of reactance and resistance of aluminum cables steel reinforced (ACSR) has been used and found to be accurate. The equipment and testing method are used to obtain accurate information concerning the a-c characteristics of all sizes of ACSR up to high values of current density, but the first use was to measure the impedance characteristics of expanded ACSR. Expanded ACSR, 1.60 inches diameter, 1,275,000 circular mils (CM), has been found to have a d-c resistance of 0.0717 ohm per mile at 25 degrees centigrade (C), a ratio of a-c to d-c resistance of about 1.015, and a reactance at 60 cycles per second (cps) at 1.0-foot spacing of 0.347 ohm per mile per conductor. This reactance value corresponds to a geometric mean radius of 0.690 inch, or 86.2 per cent of the nominal conductor radius. Expanded ACSR, 1.75 inches diameter, 1,414,000 CM, has been found to have a d-c resistance of 0.0660 ohm per mile at 25 C, a ratio of a-c to d-c resistance of about 1.015, and a reactance at 60 cps at 1.0-foot spacing of 0.337 ohm per mile per conductor. For this conductor, the reactance value corresponds to a geometric mean radius of 0.747 inch, or 85.4 per cent of the nominal conductor radius.