Calculator Guides

How to use each CableHero calculator: what to enter, how to read the result, and the clauses of AS/NZS 3000:2018 and AS/NZS 3008.1.1:2025 behind it.

Each guide walks through one of the free calculators card by card, with screenshots, a worked example and the mistakes to avoid. For the engineering background, read the blog.

Cable & wiring

How to use the cable size calculator (AS/NZS 3008.1.1:2025) Every card of the cable size calculator, from the load to the protection, and how to read the checks it runs.
How to calculate voltage drop with the voltage drop calculator Check a cable's voltage drop against the AS/NZS 3000:2018 limit, with the size fixed or chosen for you.
How to use the cable derating calculator Find the grouping, temperature, depth and soil factors and the overall derating factor they multiply to.
How to use the conduit size calculator Enter the cables by type or by diameter and find the smallest conduit within the space factor.
How to use the cable pulling calculator Build the route section by section and check pulling tension and sidewall pressure against the limits.

Protection

Solar

Design

How to use the maximum demand calculator Add the loads, let Appendix C apply the diversity, and read the demand on each phase.

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