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CALC 08 · POWERPREVIEW

Cable Sizing

Cable Sizing · Advanced Preview
Available free during the correctness audit. Results remain screening-only unless the result itself states a stronger assurance level.
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ELECTRICAL PARAMETERS

Metric (mm²) sizing is refused: no IEC 60364 or วสท. table cells are extracted or verified yet, and the legacy metric rows overstate small sizes, so the engine does not use them. Only AWG/kcmil sizes reach the sparse primary-verified NEC 2023 cells.

V
A
m

Enter positive-sequence X from the actual cable/manufacturer data. Required when power factor is below 1; VerElect will not assume zero reactance.

TERMINATION — NEC 110.14(C)
A

Required unless the equipment conductor marking below is known. Sets the termination ceiling: 60°C at 100 A or less, 75°C above 100 A — NEC 110.14(C)(1) does not permit an assumed termination temperature.

A separately installed connector stacks its listed temperature as an additional ceiling (110.14(C)(2)).

INSTALLATION CONDITIONS

Required — nothing is pre-selected. Insulation of the actual conductor (TW = 60°C, THW = 75°C, THHN = 90°C). Used as the base for temperature and CCC corrections; the final ampacity is capped by the termination ceiling resolved from the panel above.

°C

Count CCC, including applicable spares. Do not count equipment grounding conductors.

%

NEC 210.19(A)(1) / 215.2(A)(1): the conductor carries 125% of a continuous load plus 100% of a noncontinuous load. The whole load entered above is treated as the declared class; the rule text is pending primary extraction, so the factor is labelled screening in the derivation.

QUICK PRESETS
Conductor Insulation Rating Required

Select the Conductor Insulation Rating (60, 75 or 90°C) to continue. It is the Table 310.16 column the ampacity and the ambient correction are both read from, so it is a property of the conductor you are installing, not a value this page can pick for you.

CALCULATION SHEET

— AWAITING INPUT —

Enter parameters to calculate cable size

REFERENCE — SCREENING DESIGN POLICIES
Voltage-drop screening targets:
  • Branch-circuit screening target: 3% voltage drop
  • Feeder screening target: 3% voltage drop
  • Total screening target: 5% from service to load
  • Continuous loads (max current for 3 h or more): conductor sized at 125% of the continuous load, NEC 210.19(A)(1) / 215.2(A)(1) — applied only when you declare the load continuous; rule text pending primary extraction

Design-policy targets are not code-compliance evidence; verify the applicable code pack and project requirements.

Derating Factors:
  • Temperature: Higher ambient = lower ampacity
  • CCC: More than 3 current-carrying conductors requires Table 310.15(C)(1) adjustment
  • Installation: Free-air and tray paths require their own verified source rules; no synthetic uplift is used