The rack mounted system dimensions are standardized. The modules for storing equipment have a 19 inch (482.6 mm) wide front panel. For this reason, the enclosure is known as a 19 inch rack. The term “rack mounted system” actually refers to the equipment that is placed on the 19 inch rack.
All the 19 inch modules have ears that project on the sides. This permits the module to be fastened on the frames via screws. The height of the modules is in multiples of 1.75 inches (44.5 mm). This measurement is known as U or one rack unit.
The 19 inch rack setup has remained unchanged, but the equipment placed in it has changed. These dimensions are used in entertainment, audio and computing. However, the Western Electric 23-inch standard is utilized in telecommunications. It has 1.75 inch (44.5 mm) at 1-inch (25.4 mm) centers.
Rack 19 Structural Details
The rack mounted system dimensions allow for different spacing between the rear and front posts. The space most often used though is 31.5 inches (800 mm). They are also designed to contain equipment of varying depths. 39.4 inches (1,000 mm) depth measurements are not uncommon today. The greater the depth, the greater space for routing cables.
Different materials are used to make the posts. Ideally, the post should be constructed from steel. The minimum thickness required is 1.9 mm. Most manufacturers employ a 2 mm thickness for the posts. If steel isn’t used, aluminum may be considered.
They are made up of panel mounts or metal strips. These are positioned vertically. The panel mounts are 0.625 inches (15.88 mm) wide. The space between them is 17.75 inches (450.85 mm). The rack width as indicated earlier, is 19 inches (482.60 mm).
The panels have openings that are regularly spaced. All the openings are part of a horizontal pairing. The center-to-center distance is 18.312 inches (465.12 mm). The post holes are configured vertically.
The center-to-center separations are 0.5 inches (12.70 mm), 0.625 inches (15.88 mm) and 0.625 inches (15.88 mm). This means the pattern of the holes repeat themselves every 44.45 mm (1.75 inches). These racks are segregated into regions. Each has a height of 1.75 inches (44.45 mm).
The rack mounted system dimensions state that in these regions are three hole pairs. The holes are placed 0.25 inches (6.35 mm), 0.875 inches (22.23 mm), and 1.5 inches (38.10 mm) off the region’s bottom and top.