7.13.10Distribution cable impedances#

The necessary distribution cable characteristics for the particular cable installed can be determined from the following Standards or manufacturer’s data:

AS 1222.1 Steel conductors and stays – Bare overhead – Galvanized (SC / GZ)
AS 1222.2 Steel conductors and stays – Bare overhead – Aluminium clad (SC / AC)
AS 1531 Conductors – Bare overhead – Aluminium and aluminium alloy
AS 1746 Conductors – Bare overhead – Hard drawn copper
AS 3607 Conductors – Bare overhead, aluminium and aluminium alloy – Steel reinforced
AS/NZS 3008.1.1 Electrical installations – Selection of cables Part 1.1: Cables for alternating voltages up to and including 0.6 / 1 kV – Typical Australian installation conditions
AS/NZS 3560.1 Electric cables – Cross linked polyethylene insulated – Aerial bundled – For working voltages up to and including 0.6 / 1 (1,2) kV Part 1 Aluminium conductors
AS/NZS 3560.2 Electric cables – Cross linked polyethylene insulated – Aerial bundled – For working voltages up to and including 0.6 / 1 (1,2) kV Part 2: Copper conductors
AS/NZS 4026 Electric cables – For underground residential distribution systems
AS/NZS 4961 Electric cables – Polymeric insulated – For distribution and service applications (Supplements AS/NZS 4026).

Typically, the following will provide most of the common data:

Standard	Table	Cable type
AS/NZS 3008.1.1	Tables 33,39	single core aerial cables
AS/NZS 3560.1	Table E2	aerial bundled cable (ABC)
AS/NZS 4026	Table A5	distribution cables
AS/NZS 4026	Table A6	service cables

As an example of manufacturers’ data, the following has been extracted from Olex Aerial catalogue for bare AAC conductors:

Figure 7.13.10 – Typical distribution network cable characteristicsp. 153

The third column is the resistance value (R) and the fourth column is the reactance value (X) both in Ω / km. The R and X values for the distribution cables can be calculated by multiplying the Ω / km values by the cable length in km.