Commonly called the Load Class, this defines the load-carrying capability of the tray for a specific support span distance. The design and cost of the cable tray is greatly affected by this designation. In-depth guide to cable trays. An Electrician must know Electrical Abbreviations and Full Forms to read a electrical drawings. For projects that are not 100 percent defined before design start, the cost of and time used in coping with continuous changes during the engineering and drafting design phases will be substantially less for cable tray wiring. , is a welded wire-mesh cable management system made of high-strength steel wire. It is used to manage cables for light B manufactures its cable tray in a range of materials with a variety of finishes. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned in this technical guide only apply to our own cable management ranges and cannot under any circumstances be transpos regulations which.