AS/NZS 3008.1.1:2025 sets out how to select a low voltage cable for Australian conditions. It is the Australian part of AS/NZS 3008.1, and its fourth edition. This page explains what the part covers and how it is laid out. The guide on what changed from 2017 covers the changes.
What the part covers
Cl 1.1 sets the scope.
- a.c. cables up to and including 0.6/1 kV.
- d.c. cables up to and including 1500 V d.c. The d.c. scope is new in 2025.
- Australian conditions: 40 °C air and 25 °C soil. Each rating in the part applies at these conditions.
The New Zealand part is AS/NZS 3008.1.2. AmpSize reads its 2017 edition, which rates cables at 30 °C air and 15 °C soil.
The Tasmania note. Note 2 to the scope is new in 2025. Some Australian sites have conditions like those in New Zealand. At such a site, a designer may apply AS/NZS 3008.1.2. The note gives Tasmania as the example.
How the part is laid out
The part has five sections and three appendices.
| Part | What it covers |
|---|---|
| Section 1 | Scope and general matters. Cl 1.3 holds the definitions. |
| Section 2 | Cable selection: the checks a cable must pass |
| Section 3 | Current-carrying capacity: Tables 3.1 to 3.48 |
| Section 4 | Voltage drop and voltage rise: Cl 4.1 to 4.7 and Tables 4.1 to 4.31 |
| Section 5 | Short-circuit performance: Tables 5.1 to 5.5 |
| Appendix A | Worked examples of cable selection |
| Appendix B | Worked examples of the correction factors for harmonic currents |
| Appendix C | Parallel cables in a.c. circuits |
Section 3 holds each correction factor (derating factor in 2017) as well as the ratings. Tables 3.33 to 3.43 cover grouping. Tables 3.44 to 3.48 cover ambient temperature, depth and soil. Table numbers now start with the section number. The table number map gives the 2017 number of each table that AmpSize reads.
Where the d.c. material is
The d.c. material sits beside the a.c. material in each section.
- Ratings. Tables 3.21 to 3.23 cover two single-core cables. Tables 3.24 to 3.26 cover one 2-core cable. Each set has a table for 75 °C, 90 °C and 110 °C conductors.
- Resistance. Tables 4.6, 4.8 and 4.11 give d.c. resistance.
- Voltage drop. Cl 4.1.3 covers voltage drop in d.c. circuits. Cl 4.7 gives voltage drop from the mV/A.m. The d.c. mV/A.m counts both conductors of the circuit.
- Limits. Cl 4.1.1 gives the voltage drop limits. The limit depends on the type of supply.
- Worked example. Clause A.8 in Appendix A works a d.c. circuit.
A worked d.c. circuit. A 48 V battery feeds an inverter at 105 A over 4 m. Two single-core copper cables with PVC insulation run unenclosed and touching, at 40 °C. The calculator selects 35 mm² with a drop of 1.11 %. Open it in the DC cable size calculator. The d.c. cable size guide works this circuit step by step.
A worked a.c. circuit. A 230 V single-phase circuit carries 32 A over 25 m. The cable is multicore copper with PVC insulation, unenclosed and touching, at 40 °C. On the 2025 edition the calculator selects 6 mm² at 37 A. Open it on the 2025 edition.
How AS/NZS 3000 cites the part
AS/NZS 3000:2018 lists AS/NZS 3008.1.1 and AS/NZS 3008.1.2 in its normative references. It gives no year for either part. Its clauses refer to the AS/NZS 3008.1 series.
Cl 3.3.2.1 of AS/NZS 3000:2018 sets the reference air temperature: 40 °C for Australia and 30 °C for New Zealand. So the Wiring Rules name the series and the conditions, but not an edition.
The transition
- The 2025 edition supersedes AS/NZS 3008.1.1:2017.
- The publication date is 19 December 2025.
- The Preface says that regulators indicated a six-month transition from the date of publication.
Ask your regulator which edition applies to your work, and when the transition ends.
In AmpSize
Set the Standard select to AU, then pick the edition. A saved calculation or a link with no edition reads 2017. The DC cable size calculator reads the 2025 d.c. tables only. For New Zealand it corrects the AU d.c. ratings to 30 °C and marks the result Derived.
This page is a design aid. Verify every value against the current edition of the standard.