Calculate cable tray fill for ladder, ventilated trough, and solid bottom trays per NEC Article 392.22. Supports multiconductor and single conductor cables.
Based on NEC 392.22 - Number of Cables in Cable Trays
Area = cable cross-sectional area in sq inches. Adjust for exact manufacturer data.
Tray Fill
2.1%
PASSCable Area
0.5 sq in
Tray Area
23.5 sq in
Remaining
23 sq in
Calculation Breakdown
1.Tray type: Ladder
2.Tray size: 12" x 4" (usable area: 23.5 sq in)
3.Voltage level: 600V or less
4.Cable 1: 5 x #12 AWG (multiconductor) = 5 x 0.1 = 0.5 sq in
5.Total cable area: 0.5 sq in
6.NEC 392.22(A)(1): Multiconductor cables - fill must not exceed tray area (23.5 sq in)
7.Maximum allowed fill: 23.5 sq in
8.Fill percentage: 2.1%
9.Result: COMPLIANT
Per NEC 392.22: Cable fill depends on tray type, cable type, and cable size. Cables larger than 4/0 must be in a single layer. Check manufacturer specs for exact cable areas.
IMPORTANT LEGAL DISCLAIMER
For Reference Only: This calculator is provided for educational and informational purposes only. It is not intended to be a substitute for professional engineering design, advice, or certification.
Code Compliance: Calculations are based on the 2023 National Electrical Code (NEC®). However, local codes, amendments, and Authority Having Jurisdiction (AHJ) requirements vary by location and may supersede standard NEC requirements.
Verify with Your AHJ: Local Authority Having Jurisdiction (AHJ) requirements take precedence over all general code references. Contact your local building department or electrical inspector to confirm applicable codes, amendments, and permit requirements before beginning any electrical work.
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NEC Reference: NEC 392.22 - Number of Cables in Cable Trays
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