What Is MTBF (Mean Time Between Failures)?

Updated Dec 17, 2018

Issue Details

What is an MTBF, where can I find the MTBF's of NI products, and what is the process for requesting an MTBF spec for a particular product?


MTBF stands for Mean Time Between Failures. It is one of many metrics used to try to determine the reliability of a product. MTBF is a predictive metric used to attempt to forecast potential product failures based on a mathematical model of a number of factors, primarily the components and uses of components on a product. MTBF is usually measured in hours, and is listed for some of National Instrument's devices in the device specifications.

As MTBFs attempt to predict future failures based on models, it may be more or less successful in actually reflecting the reliability of a product. For National Instrument's products, MTBF is not a reliable indicator of hardware failure frequency. MTBF should not be used as a measure to predict precisely when a device will fail for NI devices.

In order to request an MTBF specification that is not already available, please contact technical support and have the following information available:
  • Model number of the NI device for which the MTBF calculation is desired (For example, the PXI-5122, the PXIe-6363, or the CompactRIO 9082).
  • MTBF model to use (For example, MIL-HDBK-217, Bellcore, etc.)
  • Environmental Conditions for the model. (For example, Ground-Fixed, Controlled or Airborne, Commercial, etc.)
  • Ambient operating temperature under test (For example, 20 degrees C, 50 degrees C, etc.)
  • Operating duty cycle (For example, is device always on, or turning on and off at regular intervals? In one year, will it operate for 100 hours or 5,000 hours?)

Additional Information

Requesting an MTBF analysis does not guarantee National Instruments will be able to provide the requested specification.


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