// FREE CALCULATORS
Cable Tray Fill Calculator
Screen cable tray fill by cross-sectional area against common design-practice limits: ladder/ventilated trough (50%) or solid-bottom tray (40%). Also shows the sum of cable diameters for the NEC 392.22(A) check on cables 4/0 AWG and larger. A screening tool, not the code method.
// INPUTS
// Results update automatically as you type
// TRAY
inches (NEC)
inches (NEC)
// CABLES
inches (NEC)
Tray Internal Area
-in²
Total Cable Area
-in²
Fill Percentage
-%
Permitted Fill Limit
-%
Status
-
Disclaimer: This tool applies a general area-fill screen (50% / 40% of the tray cross-section), which are design-practice limits and not percentages from the NEC. NEC 392.22(A) sets fill differently: for multiconductor cables 4/0 AWG and larger, the sum of the cable diameters must not exceed the tray width in a single layer; for smaller cables, the sum of the cable cross-sectional areas is compared with the allowable fill area in Table 392.22(A) for the tray width (with separate rules for mixed sizes, solid-bottom trays and single conductors in 392.22(B)). Verify against NEC 392.22 directly for code-compliance sign-off. Ampacity derating is a separate check: see the Cable Ampacity Calculator. Found an error or an outdated reference? Let us know at [email protected].
Please check inputs, all values must be positive.