A box type cable tray vertical outside bend is a fitting used to change the direction of a cable tray system vertically, typically at a 90-degree angle, directing cables outward. How to calculate cable tray bends? Calculate the minimum required bend radius by multiplying the cable's outside diameter by its bending factor (e. Then, select a standard tray fitting (300mm, 450mm, etc. ) that matches or exceeds this value. Use this tool to estimate sloped section length, horizontal run requirement, cut marks, and installation feasibility. Measure this distance along the straight tray. 90° bend, Vertical Inner Bend, for all cable tray types of 50 mm side height. How to bend 90 degree of cable tray 3 line with the same distance :// • HOW TO BEND 90 DEGREE OF CABLE TRAY 3 LINE.