ni.com/calibration

ni.com/calibration

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

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Acceptance of your instrument’s measurement capabilities between countries

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Ability to determine the maximum uncertainty of your measurements

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Correlation between your measurements and those of other traceable entities

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.

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.

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.

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.

DKD

National Instruments

TRT

SIMT

ST Electronics

Davis Calibration

ESZ

Japan (NIMJ AIST)

China (NIM)

Singapore (NMC)

USA (NIST)

Germany (PTB)

Bureau International des Poids et Mesures (BIPM)

ACLASS

SAC

SINGLAS

East China

National

Centre of

Metrology

JNLA

Manufacturing

Facilities

Metrology

Laboratories

Accreditation

Services

National

Metrology

Authorities

International

System of Units

(SI)

NI Traceability

Tracing your instruments’ accuracy to known standards is a critical part of calibration.

NI provides a full range of calibration services.