As a manufacturer of high-accuracy measurement products, National Instruments
understands the need to maintain properly calibrated equipment. Calibration is the
comparison of an instrument’s actual measurement performance to a standard of known
accuracy. With calibration, you can achieve the following:
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Ensure accurate measurements
Trace measurements back to known and accepted standards
Increase production yields
Meet quality program requirements such as ISO 9001
Provide a basis for comparing measurements between different users
Critical for maintaining performance and accuracy, calibration can be performed on a wide range of instruments.
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Calibration Intervals
The accuracy of the electronic components of all instruments drifts over time, with factors such as time in service
and environmental conditions contributing. Devices are designed and tested so this error is noted in accuracy
specifications, but after a defined length of time called the calibration interval, most manufacturers no longer specify
the measurement accuracy. To maintain specified measurement performance, instruments must be calibrated at regular
intervals as defined by the manufacturer.
Self-Calibration
Self-calibration, or internal calibration, uses onboard signal references to adjust measurement accuracy. During
self-calibration, the instrument measures the onboard references and adjusts its measured performance to account
for changes due to environmental effects such as temperature.
The adjustment of measured values during self-calibration does not account for the drift of the onboard signal reference
and does not replace the need for external calibration. Performing regular external calibration helps ensure the onboard
reference signals are accurate and maximizes overall measurement performance.
External Calibration
0.01%
24 Hours
90 Days
1 Year
?
Error
Time
There are a number of reasons to send an instrument to the manufacturer or a suitable metrology laboratory for external
calibration, including when you need to verify performance, when the calibration interval has expired or your predefined
service time has elapsed, when the instrument has been operated in an extreme environment, or when measurements
appear questionable. External calibration includes verification of the instrument’s capabilities and provides for adjustments
to measurement circuitry and onboard signal references if needed. Typically, a calibration certificate is issued verifying the
instrument’s measurement performance at the time of calibration.
System Calibration
System calibration, the most comprehensive method of calibration, quantifies and compensates for the total
measurement error in a system. By applying known inputs and reviewing the resulting measurement, you can develop a
model that represents the error of the system and compensate for this error by applying correction coefficients to your
measured data.
-0.01%
Accuracy Specifications
For most computer-based data acquisition and instrumentation hardware, NI supplies graduated accuracy tables.
ni.com/calibration
Computer-based data acquisition and instrumentation hardware is ideal for this type of compensation because you can
quickly and easily apply your correction in software. System calibration does not completely replace the need to perform
external calibration on individual system components in order to meet the requirements of quality programs.
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
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 Calibration Certification
To help meet your calibration needs, National Instruments provides calibration support and services. These options
include product recalibration services, manual calibration procedures, and automated calibration software specifically
designed for metrology laboratory use. Used as part of your complete calibration solution, these offerings can help you
ensure the accuracy of your instruments.
NI Calibration Service
National Instruments offers two service options for maintaining your instrument’s measurement performance: Basic
and Detailed Calibration. You can obtain these services for your instrument at the time of purchase, or anytime after,
to maintain the instrument’s performance.
After the calibration interval expires, you can return your products to NI for recalibration. To order recalibration, contact
National Instruments to obtain a calibration Return Merchandise Authorization (RMA) number and specify the type of
calibration service when you order.
Through independent calibration service providers, you can obtain additional NI product calibration services such as
express calibration service, on-site calibration services, and calibration for all of your measurement hardware including
instrumentation products that are not from NI.
NI offers calibration solutions for all of your instrumentation, even hardware for other companies.
Basic Calibration
NI offers a Basic Calibration certificate with all new measurement products at no charge to you. This certificate states
that the product is calibrated and provides traceability to internationally accepted standards, which can help you meet the
requirements of quality standards programs such as ISO 9001.
Detailed Calibration
If your quality requirements state that you need more than a Basic Calibration certificate, NI offers Detailed Calibration
service. Detailed Calibration certificates from NI contain detailed measurement data to help you meet the requirements
of even more stringent internationally accepted quality standards. NI offers Detailed Calibration certificates for purchase
at the time you acquire your measurement hardware.
Manual Calibration Procedures
To support more advanced metrology laboratories, NI provides access to manual calibration procedures, which offer detailed
step-by-step instructions for verifying and adjusting the performance of NI products during calibration. These documents
also define the required calibration standards, software functions, and test specifications used during the calibration.
NI Calibration Executive
Using manual calibration procedures can be slow and can require software development to adjust measurement
hardware. For users and laboratories that do not have the time or expertise to develop their own calibration software,
NI provides a turnkey calibration application – NI Calibration Executive.
NI Calibration Executive, which was developed primarily for metrology laboratories, automates the verification and
adjustment of your NI products. By using NI Calibration Executive, you can easily automate your calibration operations and
benefit from NI technology such as NI-VISA universal I/O interface software, IVI drivers, and NI TestStand and LabVIEW
software. NI Calibration Executive:
Externally calibrates most NI measurement devices
Operates in automatic or manual mode through an intuitive user interface
Automatically configures and controls calibration instruments
Stores calibration reports in an ODBC-compliant database
Provides convenient connections through hardware calibration fixtures
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NI Calibration Services
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NI Global Services and Support
National Instruments offers extensive services and support solutions to help you achieve long-term success. Take
advantage of product and professional services, training, and certification programs to meet your needs during each
phase of the application life cycle – from planning and development through deployment and ongoing maintenance.
Visit
ni.com/services
for more information.
Professional Services
The NI professional services team, comprising NI engineers and worldwide National Instruments Alliance Partners,
can help you with prototyping, feasibility analysis, consulting, and systems integration. Visit
ni.com/services
for more
information.
Software Maintenance and Support
Visit
ni.com/ssp
to learn how, as a National Instruments Standard Service Program (SSP) member, you can receive free
software upgrades and maintenance releases, direct mail and phone support from NI applications engineers, and access
to exclusive software training modules.
Hardware Services
Make the most of your hardware investment by using NI hardware services including flexible and renewable extended
warranties, time-critical repair services, and hardware recalibration options. Visit
ni.com/services
for more information.
Training and Certification
The NI training and certification program is the most effective way to increase application development proficiency and
productivity using NI software and hardware. Visit
ni.com/training
for more information.
Volume Licensing
Designed for organizations with five or more licenses of the same software program, the Volume License Program
features services such as centralized license management, flexible budget purchasing, customized on-site training,
and more. Visit
ni.com/vlp
for more information.
Ordering Information
NI Calibration Executive .......................................................................................................................... 777608-02
NI Calibration Executive hardware adapter for NI E Series, M Series, and S Series devices ................. 778056-03
NI Calibration Executive hardware adapter for NI 435x devices ............................................................. 778031-03
NI FP-TB-CAL calibration base for FieldPoint .......................................................................................... 777519-90
NI cFP-CAL calibration backplane for Compact FieldPoint ..................................................................... 779646-01
Visit
ni.com/calibration
for a current list of applicable products, calibration services part numbers, and pricing.
U.S. Corporate Headquarters
866 463 5417
Worldwide Offices
(Please note that these phone numbers do not include their respective country codes):
A National Instruments Alliance Partner is a business entity independent from National Instruments and has no agency, partnership, or joint-venture relationship with National Instruments.
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