Support Methods: Common support methods include trapeze hangers, which are used for ceiling suspensions, and cantilever wall brackets, which are mounted directly to walls for runs along vertical surfaces. The choice depends on the building structure and the planned tray route. Cable Tray Support Span: The distance between supports is a critical calculation. It instructs us on how to construct them, where to locate them, and how to stuff them with wires without using too much. These regulations ensure that the metal or plastic frames that contain the wires are robust enough to ensure. association representing the major electrical equipment manufac-turers in the U. Establishing partnerships.