The cable trays consist of a thin metallic plate and electro-welded steel rods. Their construction is based on the international standard IEC 61537, which specifies the requirements for cable tray systems, tests, and specifications. Galvanized tray may be made of pre-galvanized steel sheet fabricated into tray, or may be hot-dip. There are several types of cable trays, including ladder, perforated, solid bottom, basket, and channel trays.