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Cable Ampacity Derating

Apply temperature correction and grouping factors to cable base ampacity per NEC Table 310.16 and IEC 60364-5-52. Instant adequacy check against design load current.

Apply temperature correction and grouping/bundling factors to cable base ampacity. Base values from NEC Table 310.16 (60/75/90°C ratings, copper and aluminium). Temperature correction per NEC Table 310.15(B)(1) (30°C base) or IEC 60364-5-52 (40°C base). Grouping factors per NEC Table 310.15(C)(1) or IEC B.52.17. Supports conduit, cable tray, and direct burial installation methods.
// INPUTS
// Results update automatically as you type
Reference: 30°C (NEC) / 40°C (IEC, varies)
Neutral counts if carrying unbalanced load (NEC)
Enter manufacturer nameplate ampacity if known
Actual current the cable needs to carry
Base Ampacity (table) A
Temperature Correction Factor
Grouping / Bundling Factor
Derated Ampacity A
Design Load Current A
Status
Disclaimer: For reference and preliminary estimation only. Verify results against the applicable code, project specification, and equipment data before use in design documents.
Please check inputs.
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