Cable Sizing Calculator
AS/NZS 3008.1 current-carrying capacity with full derating — grouping (Table 22), ambient temperature, and installation method. Volt drop checked to AS/NZS 3000 cl. 3.6 (≤5%). Copper conductors.
Circuit details
V75 = standard TPS, V90 = XLPE singles or twin
Rated base temp: V75 = 75°C, V90 = 90°C
How this works: Base current ratings are from AS/NZS 3008.1 Table 7 (copper, clipped direct). Installation method derating per Table 21 / reference method factors. Grouping derating per Table 22. Temperature correction per Table 27 (V75) and Table 28 (V90). Volt drop: 2×I×R×L/1000 (single phase) or √3×I×R×L/1000 (three phase). Resistance values from AS/NZS 3008.1 Table 34 (at operating temperature).
Always verify final cable selection against AS/NZS 3008.1 tables on the job. Apply additional derating for thermal insulation, high-temperature locations, and harmonic loading as required. This tool is a guide — a licensed electrician must confirm the design.