Input Cable Schedule: Select standard cables from the dropdown menu or manually enter the Outer Diameter (OD) and Quantity. If the bar turns RED, you need a larger tray. Cable tray is the preferred wiring method for industrial facilities, data centers, and large commercial buildings where routing dozens or. Determine the total usable cross-sectional area of the cable tray by multiplying its width by its height (or depth). Proper tray and ladder sizing ensures safe, efficient, and maintainable electrical installations in all engineering applications. IEC 61537 and IEC 60364 require evaluating tray dimensions based on cable quantity, type, and layout configuration. Follow these simple steps: Define Tray Dimensions: Enter the width and depth of your planned cable tray (in mm or inches).