The Importance of Traceability
One of the most basic requirements of calibration is proof of traceability, an unbroken
chain of comparisons between an instrument’s measurement and a known standard.
Because these well-quantified standards are maintained by national and international
organizations, they provide a reference for all traceable measurements. Traceability
between your measurements and these standards provides the following advantages:
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The ability to trace your measurement uncertainty back to an accepted standard
Acceptance of your instrument’s measurement capabilities between countries
Ability to determine the maximum uncertainty of your measurements
Correlation between your measurements and those of other traceable entities
NI provides a full range of calibration services.
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Traceability is defined at a number of levels. The Bureau International des Poids et Mesures (BIPM) ensures worldwide
uniformity of measurements and their traceability to the International System of Units (SI). It does this with the authority
of the Convention of the Metre, a diplomatic treaty among member nations. The BIPM also participates in and organizes
international comparisons of national measurement standards, as well as conducts calibrations for member states.
NI Traceability
International
System of Units
(SI)
Further down the chain, at the national level, each country has different legal metrology authorities. These bodies follow
the guidelines defined by the BIPM and its associated committees to provide quality measurement standards for their
associated countries. The National Metrology Institute (NMI) of each member state of the Convention of the Metre also
participates in the Mutual Recognition Agreement (MRA). This document provides, among other things, a mutual
recognition of calibration and measurement certificates issued by NMI.
Finally, each country has accreditation institutes that audit and accredit local metrology laboratories to the standards set
forth by their NMI. In Europe, many of these accreditation institutes participate in the EA Multilateral Agreement (MLA)
to ensure that accreditations in one country are acceptable in others.
Bureau International des Poids et Mesures (BIPM)
National
Metrology
Authorities
Germany (PTB)
USA (NIST)
Singapore (NMC)
China (NIM)
Japan (NIMJ AIST)
Calibration and the NI Hardware Advantage
National Instruments computer-based data acquisition and instrumentation hardware is calibrated at the factory to ensure
measurement accuracy and to verify that the devices meet published specifications.
Accreditation
Services
DKD
ACLASS
SAC
SINGLAS
East China
National
Centre of
Metrology
JNLA
Metrology
Laboratories
ESZ
Davis Calibration
ST Electronics
SIMT
TRT
NI products calibrated at the time of manufacture are traceable to international standards such as the National Institute of
Standards and Technologies (NIST) in the Americas and the Physikalisch-Technische Bundesanstalt (PTB) in Europe. By
performing calibration traceable to these standards, NI can help ensure that measurements taken in one country are
accepted in all other participating countries. With this calibration, NI provides a certificate of calibration recognized in all
countries as documented proof that the hardware meets published specifications. To maintain maximum measurement
performance, NI can recalibrate your NI products to meet factory specifications.
Unlike traditional box instruments, computer-based hardware uses software applications that you create to define your
measurement functionality. In this way, you can easily add error compensation and automate system calibration in your
application software. By regularly calibrating your NI hardware and taking advantage of the flexibility that comes with
software-defined instruments, you can maintain unquestionable measurement performance.
Manufacturing
Facilities
National Instruments
Tracing your instruments’ accuracy to known standards is a critical part of calibration.
ni.com/calibration
ni.com/calibration
NI [ NATIONAL INSTRUMENTS CORPORATION ]
