Rack unit

One rack unit ( Unit English, short or U Rack Unit, short- RU), HE for short, is an electronics housing (English rack) used units to describe the height of the unit. Devices with a height unit as "1U " (or " 1U " ) refers to devices with two height units as "2U ", etc. 1 U corresponds to 1 ¾ inch, or 44.45 millimeters.

Product enclosure that may be measured according to HE are intended for installation in the so-called 19 "racks. The width of the 19 " front panels corresponds to 482.6 mm. The typical height of a rack is 42U.

Many a time is jokingly referred to as a pizza box, a server with a height unit because of the housing form.

Applications

Of particular importance is the HE to data centers. There the computer are often operated in 19 "racks with limited height and you pay at the accommodation ( Server Housing ) of a device, among other things for the required height units.

Furthermore, HE also be used in the field of sound and staging as a measure of the height of technical devices. Almost the entire signal chain here can be housed in 19 "rack, from the mixer to the final stage.

Other applications are in telecommunication systems, the broadcasting technique in measuring devices and in medical technology.