Cable Size Calculator updated with 2025 version of AS/NZS 3008


Hi Reader

I am just letting you know.

I have added the 2025 version of AS/NZS 3008 to the Cable Size Calculator.

This version applies to Australian conditions only.

You can still use the 2017 version.

Note that Standards New Zealand has not yet published the 2025 version of the New Zealand standard.

Summary of 2025 changes applicable to the Cable Size Calculator

  • New table numbers.
  • Dedicated current ratings for DC circuits.
  • Combined current ratings for flexible and non-flexible copper conductors.
  • Added current ratings for 110°C aluminium cables.
  • Updated current ratings for directly buried cables up to and including 10 mm².
  • Expanded current ratings for two single-core cables, up to 630 mm², installed in wiring enclosures in air.
  • Expanded current ratings for 110°C multicore cables installed in thermal insulation.
  • Updated air-temperature derating factors.
  • Updated soil-temperature derating factors.
  • Updated cable-depth derating factors.
  • Added dedicated DC resistance tables.
  • Expanded resistance values to include conductor temperatures of 25°C and 30°C.
  • Updated short-circuit fault constants.

Click here to try.

Please let me know if you have any questions or suggestions.

I appreciate your feedback.

Adam van Staden
​LinkedIn Profile​
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This information does not constitute legal, professional or commercial advice. JCalc Pty Ltd gives no guarantees, undertakings or warranties in this regard, and does not accept any legal liability or responsibility for the content or the accuracy of the information so provided, or, for any loss or damage caused arising directly or indirectly in connection with reliance on the use of such information.

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