Click "Calculate" to see the minimum bending radius and the recommended standard tray bend radius (300mm to 900mm) required for safe installation. Tray bend radius must be ≥ minimum cable bend radius. Use the largest cable diameter in the tray for calculation. This inside measurement is the most common definition of bend radius across industries, whether you're working with sheet metal, electrical. Our customers occasionally ask us: “How tight can I get away with bending this cable?” when installing wire and cable in trays with curves, in ducts, around building corners or around sheaves. When bent too sharply, helical metal tapes can eparate. In the attached sketch, the width of the cable tray is 12".