Bob Stern Agilent Senior Metrologist
NCSLI member delegate Co-chair, 174 Standards Writing Committee Member, 171 Z540.3 Handbook Committee Member, Agilent Cal Cert Working Group Member, ILAC-P14 compliance project
How to Comply with
ANSI Z540.3
1
2
Why Calibrate What is it?
Calibration Adjustments Who can do it?
Measurement Uncertainty How accurate?
3
4 Traceability Why important?
5 Standards
Compliance Which ones?
Accreditation Why it matters? 6
7 Z540.3
Compliance How?
Calibration Modules
Nov 13
Dec 13
Dec 13
Jan 15
Feb13
Why Calibrate? 1
YouTube calibration videos
www.YouTube.com/AgilentCalRepair
1 Why Calibrate http://youtu.be/HwSxBRaxn_4
2 Adjustments http://youtu.be/IqsLmYgtoOg
3 Accuracy/Uncertainty http://youtu.be/ENvl8BYzMG0
4 Traceability http://youtu.be/-eMQ0KakIyQ
5 Standards compliance http://youtu.be/8s2Xx3C0_ds
6 Accreditation http://youtu.be/SH2wewUBlr8
7 ANSI Z540.3 http://youtu.be/4P8alkNAQ24
9 min
Why Calibrate? 1
What is calibration?
1. Characterize your
device/instrument
Measure the actual performance!
2. How Accurate? Measurement Uncertainty
3. Pass or Fail? Statement of Conformance
4. Advise client if found
out-of-tolerance.
Adjust, if instructed, and repeat
calibration.
Formal definition at: http://www.bipm.org/utils/common/documents/jcgm/JCGM_200_2012.pdf
Measurement Uncertainty 3
Test point Pass/Fail labeling challenge
Nominal
Upper specification
Lower specification
2U
Span of the tolerance
TUR = Test Uncertainty Ratio, paragraph 3.11 ANSI Z540.3
Span of the tolerance
2U TUR=
Z540.3 Compliance 7
Power Measurement Uncertainty
Application Notes 1449 series http://cp.literature.agilent.com/litweb/pdf/5988-9215EN.pdf
Setup for Maximum Leveled Output Power Measurement
u(Mu) Mismatch uncertainty, sensor & sig-gen
u(Muc) Mismatch uncertainty, sensor & cal output
u(Kb) Sensor calibration factor uncertainty u(Pl) Sensor linearity uncertainty
u(N) Sensor and meter noise uncertainty
U(Pcal) Calibrator output level uncertainty
U(Zs) Power meter zero set uncertainty
U(Zs) Power meter instrumentation uncertainty
U(D) Power meter drift uncertainty
Where does the Z540-1 term, “4:1”come from?
Test Uncertainty ratio (TUR) should be > 4:1
Source: Z540-1 paragraph 10.2b
Z540.2 is the American English version of the ISO GUM
Z540.3 Compliance 7
ANSI / NCSL Z540.3
Addressing Global Requirements
ANSI / NCSL Z540-1
ISO/IEC 17025
EURAMET/cg-15/v.01 (previously EA 04/13)
ILAC-G8
“When statements of compliance are made, the uncertainty
of measurements shall be taken into account”
paragraph 5.10.4.2
Z540.3 Compliance 7
ANSI / NCSL Z540.3
Addressing Global Requirements
ANSI / NCSL Z540-1
ISO/IEC 17025
EURAMET/cg-15/v.01 (previously EA 04/13)
ILAC-G8 Upper Tolerance
Case 1 Case 2 Case 3 Case 4
ILAC-G8 Guidelines on the Reporting of
Compliance with Specification
Z540.3 Compliance 7
ANSI / NCSL Z540.3
Addressing Global Requirements
ANSI / NCSL Z540-1
ISO/IEC 17025
EURAMET/cg-15/v.01 (previously EA 04/13)
ILAC-G8
“Where calibrations provide for verification that measurement quantities
are within specified tolerances, the probability that incorrect acceptance
decisions (false accept) will result from calibration test shall not exceed 2%...”
paragraph 5.3b
Z540.3 Compliance 7
Probability of false acceptance
Nominal
Upper specification
Lower specification
Paragraph 5.3b: “Where calibrations provide
for verification that measurement quantities
are within specified tolerances, the
probability that incorrect acceptance
decisions (false accept) will result from
calibration tests shall not exceed 2% and
shall be documented…”
Z540.3 Compliance 7
Integrate the joint probability density function
Device Population Error Calibration Process Uncertainty
. . . or get the Z540.3 Handbook
Z540.3 Compliance 7
Get the Z540.3 Handbook
• Excellent tutorial on Probability of False
Acceptance (PFA)
• Details on 6 compliance methods
• Available from the NCSLI on-line store
www.ncsli.org
Hint: If you’re new to Z540.3 start reading
In Appendix A.
Z540.3 Compliance 7
www.ncsli.org
Z540.3 Compliance 7
Z540.3 compliance information requirements
NCSLI Z540.3
Handbook
Compliance
Method
Information Requirements M&TE
Test
Tolerances
M&TE
Test Point
Measurement
Reliability
M&TE
Overall
Measurement
Reliability
Calibration
Process
Measurement
Uncertainty
Test Point Population
M&TE Population
Acceptance Subpopulation
Bayesian
Expanded Uncertainty
Managed Guardband ISO GUM / Z540.2
Z540.3 Compliance 7
“89% Rule compliance method” / NASA
>89% end-of-period reliability (EOPR) results in < 2% PFA
• In use at NASA
• MSC & NCSLI papers by Paul Reese, Jonathon Harben, Scott Mimbs, Perry King
• March 2012 Measure Magazine article, “Risk Mitigation Strategies for
Compliance Testing”, contact [email protected]
Z540.3 Compliance 7
Did you know?
Source: www.ilac.org “Guidelines on Assessment and Reporting of Compliance with Specification – ILAC-G8:1996”
“Pass” per ILAC-G8 is identical
to a “Pass” using Z540.3 Handbook
compliance method 5
Z540.3 Compliance 7
Z540.3 cal available now for > 700 instruments
www.agilent.com/find/americas_cal
Z540.3 Compliance 7
Sample calibration certificate
Z540.3 Compliance 7
Agilent N7800 calibration & adjustment software
covers over 190 instruments
www.agilent.com/find/calibrationsoftware
Factory calibration
Factory instrument production process flow (simplified)
Yes
No
Final test
(EI) Pass?
Done
adjustments Diagnose Load bare
boards/solder
“bed of nails”
board test
Final
assembly
Courtesy of Ed Dempsey, Santa Rosa. “EI” is electronic inspection
Every warranted & typical spec
measured vs. Test Line Limit
Do new instruments comply with Z540.3 ?
Z540.3 Compliance 7
Setting Specifications at Agilent Technologies
Source: Setting and Using Specifications, Michael Dobbert, Sept 2010 issue, Measure Magazine
Production Margin
Expanded Measurement
Uncertainty
Test Line Limit
Specification
Delta Environmental and Drift
New instruments from the factory comply with ISO/IEC 17025, ILAC-G8,
and ANSI/NCSL Z540.3-2006
Z540.3 Compliance 7
Where to get more info on Z540.3
www.agilent.com/find/Z540.3
Z540.3 Compliance 7
Summary: How to comply with Z540.3
• You need Measurement Uncertainty (Z540.2 / ISO GUM) for your cal procedures
• This answers “How accurate is this measurement?”
• Get/read the NCSLI Z540.3 Handbook
• Tutorial on PFA
• Descriptions & examples for 6 published methods
• Pick the method that works best for you.
• Prioritize the instruments/families that matter most to your organization.
• If you send out your instruments for Z540.3 cal, ask to see example reports
of what you’ll receive.
Z540.3 Compliance 7
Agilent compliance to Z540.3
If you buy new instruments from Agilent Technologies and. . .
either send your instruments to Agilent for “Agilent cal +
Uncertainties + Guardbanding” cal service or
use Agilent N7800A Calibration & Adjustment Software. . .
then you comply with Z540.3
Agilent performs Z540.3 calibration for over 700
models today.
Why Calibrate? 1
On Demand Calibration Webcasts:
www.agilent.com/find/calibrationwebcasts
w
4) 13 Feb 2013 “How to Comply with ANSI Z540.3”
Now On-Demand:
1) 8 Nov 2012 “Calibration: Why it Matters to You and What it Should Include”
2) 13 Dec 2012 “Calibration Traceability & Standards Compliance”
3) 15 Jan 2013 “De-Mystifying Calibration Accreditation”
Questions and Answers
