The meaning of the letter U
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Nowadays, cabinets are specified in terms of U units. For example, a cabinet with dimensions of 2100×800×600 is denoted as 42U by the manufacturer. I would like to ask what U means and what the size of one U is
U should represent the total height of the equipment placed inside the cabinet. 1U equals 44.45 mm; 42U means 42 times 44.45 mm, which is its height. For a cabinet, this height refers only to the internal space height (that is, the height of the panels, excluding the upper and lower frames as well as the casters) ； If it’s a plug-in box, then it’s the external dimensions minus the gaps. For specific dimensions, refer to the international standard IEC60297. This post was last edited by Free Dust on 2009-2-11 16:40]
Thank you, LS. I’d like to ask further: what are the standards for the width and length of 1U?
Rack servers have a width of 19 inches, and their height is measured in U units (1U = 1.75 inches = 44.45 millimeters). There are typically standard server heights of 1U, 2U, 3U, 4U, 5U, and 7U.
Are all servers from manufacturers 19U wide? Also, why aren’t there servers with a 6U height? It’s strange...
I cannot find the IEC60297 standard. Are there any other standards that provide detailed specifications regarding free dust? Please let me know, thank you
U is the internationally standard unit for measuring the height of cabinets; the standard width is 19 inches. It is not used only for wiring products – the height of any mechanical or electrical equipment is expressed in terms of U. 1u=44.5mm=1.75 inches is an abbreviation for unit; the detailed dimensions are determined by the Electronic Industries Alliance (EIA), a standards-setting organization.