Data Center Cabling Solutions
Common Units of Measurement in Data Center Cabling

Common Units of Measurement in Data Center Cabling

  • Jul 31, 2012
  • units of measure, data center cabling, data center
  • tkelly

Are you familiar with common units of measurement used when referring to data center cabling? Understanding these terms will help you effectively communicate with your team or a vendor, particularly useful when ordering or installing new cable.

Common Units of Measurement for Data Center Cabling:

Meter – measures length; one meter equals 3.2808 feet

Kilometer – measures very long distances; one kilometer equals 1000 meters, 3,281 feet or 0.62 miles

Micrometer (µm) or micron – measures very short lengths; one micrometer equals 1 millionth of a meter. It is used to express the diameter of fibers. For example, the diameter of the core of an OM3 standard fiber cable is 50 µm or 50 microns, and the diameter of the cladding is 125 microns. This is the most common term in the measurement of fiber. See diagram below for example.


Nanometer ( nm) – measures extremely short lengths; one nanometer equals 1 billionth of a meter. This measurement is used when talking about the wavelength of light. The period at the end of this sentence is 1,000,000 nanometers wide.

Decibel, or dB, is the unit for measuring the relative differences in the strength of light signals. It is a common measurement used to determine loss or gain in a system.