The horizontal distance between the centers of the left and right mounting holes is strictly defined as 18.312 inches (465.1 mm). 2. The Rack Unit (U or RU) Height
Many people, and even some manufacturers, use the terms "EIA-310-D" and "EIA-310" interchangeably. But what exactly is the difference? Understanding the standard's evolution helps clarify this.
To summarize the critical takeaways:
Vertical space in a server rack is measured in Rack Units, abbreviated as "U" or "RU."
The confusion stems from the fact that the "D" revision is so iconic and widely used that it remains the name of choice for many in the industry. For practical purposes, a rack that complies with EIA-310-E also complies with the functional mounting requirements of EIA-310-D. The main difference is often found in the naming conventions due to the change in governing bodies. eia310d standard pdf
: This is the fundamental unit of vertical measurement. One “U” is exactly 1.75 inches (44.45 mm) tall. This unit allows for the modular design of equipment; for example, a 2U server requires 3.5 inches of vertical rack space.
: The primary source for purchasing EIA/ECA-310-E (the current revision). The horizontal distance between the centers of the
Minimum 17.75 inches (450.8 mm) 3. Rail Hole Types Covered Under the Standard
Here is a sample PDF of EIA-310D standard: https://www.ecia.org/eia-310d-standard But what exactly is the difference