Would you like a short checklist for choosing racks/equipment (U sizing, depth, mounting holes, accessories)?
is a standard established by the Electronic Industries Alliance (EIA) for cabinets, racks, panels, and associated equipment. It defines the mechanical dimensions—primarily height, width, and mounting hole patterns—for 19-inch racks and cabinets. Standard Designation: EIA-310-D
I can’t directly provide or link to a PDF of the standard (officially EIA Standard 310-D: Cabinets, Racks, Panels, and Associated Equipment ), as it is a copyrighted document owned by the Electronic Industries Alliance (EIA) — now managed by Global Engineering Documents and other standards distributors.
They accept cage nuts, which house replaceable threads. If a thread strips, you simply replace the cage nut rather than discarding the entire rail. Square holes also support toolless slide rails, speeding up server deployment. Round Unthreaded Holes Design: Circular clearances without internal threads. eia310d standard pdf
To summarize the critical takeaways:
While the standard has been updated over time—succeeded by EIA-310-E and the current CEA-310-F standard managed by the Consumer Technology Association (CTA)—engineers, IT buyers, and facility managers still frequently search for the original EIA-310-D PDF to verify legacy systems and compliance baselines. Core Dimensional Specifications of EIA-310-D
from the second hole to the third hole.
Commonly used in telecommunications, two-post relay racks, and AV environments. The holes are pre-threaded, usually for 10-32 or 12-24 screws.
Employs cage nuts , which snap securely into the square holes.
EIA-310-D does not specify the external dimensions of the rack cabinet (width, depth, height) – only the internal mounting interface. This is why a 19-inch rack from two manufacturers can have vastly different external footprints. Would you like a short checklist for choosing
Because the underlying dimensions did not change between revisions D and E, equipment built to EIA-310-D specifications remains fully compatible with modern server cabinets sold today. 6. How to Access the Standard
: The spacing between vertical rows of mounting holes is specified as 18.312 inches (465.1 mm) .
For 95% of standard IT gear (servers, switches, UPS), compliance with EIA-310-D implies compliance with E. However, if you are building a seismic-rated rack for California or Japan, you need EIA-310-E. Square holes also support toolless slide rails, speeding