Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.44
The Standards and Calibration Laboratory (SCL) in Hong Kong has developed a measurement system for the testing of electrosurgical unit (ESU) analyzers. ESUs are medical device widely used by surgeons and medical practitioners in surgical operations and in outpatient procedures. ESUs generate high frequency signals usually in the range of 200 kHz to 500 kHz with power up to 300 W to heat up tissues by induced intracellular oscillation of ionized molecules. By precisely controlling the power and duty cycle of the output waveform, various electrosurgical procedures including cut, coagulate, desiccate, fulgurate or spray of tissues can be performed. Routine performance check of ESUs is commonly conducted by ESU analyzers, which is a high frequency electronic load designed to measure the output parameters of various ESU modes. In this paper a method developed for the testing of ESU analyzers at the SCL is presented. By utilizing high speed digital sampling system, high frequency arbitrary power waveforms measurement function of ESU analyzers can be tested by simultaneous measurement of voltage and current components.
{"title":"Arbitrary Power Waveforms Measurement for Electrosurgical Unit Analyzers","authors":"","doi":"10.51843/wsproceedings.2018.44","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.44","url":null,"abstract":"The Standards and Calibration Laboratory (SCL) in Hong Kong has developed a measurement system for the testing of electrosurgical unit (ESU) analyzers. ESUs are medical device widely used by surgeons and medical practitioners in surgical operations and in outpatient procedures. ESUs generate high frequency signals usually in the range of 200 kHz to 500 kHz with power up to 300 W to heat up tissues by induced intracellular oscillation of ionized molecules. By precisely controlling the power and duty cycle of the output waveform, various electrosurgical procedures including cut, coagulate, desiccate, fulgurate or spray of tissues can be performed. Routine performance check of ESUs is commonly conducted by ESU analyzers, which is a high frequency electronic load designed to measure the output parameters of various ESU modes. In this paper a method developed for the testing of ESU analyzers at the SCL is presented. By utilizing high speed digital sampling system, high frequency arbitrary power waveforms measurement function of ESU analyzers can be tested by simultaneous measurement of voltage and current components.","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116370000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.07
J. Fuehne
The Purdue Polytechnic Institute is one of ten colleges on the campus of Purdue University in West Lafayette, Indiana. Also included in the Institute is an outreach effort that includes ten locations spread throughout the state of Indiana to engage local communities and industries and to provide an alternative to the main campus for traditional and non-traditional students in those geographic areas. One of those areas is Columbus, Indiana, about an hour south of Indianapolis, and this paper relates experiences from that location. The Purdue Polytechnic Institute in Columbus, working together with corporate partner Cummins Inc., has developed a metrology training program that includes competency-based credentialing based on hands-on activities rather than a written test. This work includes specific details of the training program with activities required for competency-based credentialing. Many training programs include only a lecture/discussion format that usually include some written examination to demonstrate competency. In this plan, the Purdue Polytechnic Institute in Columbus utilizes metrology tools with targeted measurement artifacts, which may be 3-D printed, to facilitate learning and provide opportunities to demonstrate competency, leading to badges awarded by Purdue Polytechnic Institute for satisfactory performance. Criteria for earning the badges is also presented as well as tiered, layered approach to earning multiple badges. These metrology topics include dimensional metrology, surface finish metrology, and pressure metrology. Dimensional metrology is further layered for specific competencies involving different tools. Ultimately, this plan and effort will culminate in industry-accepted certifications based on earned badges and demonstrated competencies that are recognized throughout the manufacturing and measurement industries.
{"title":"A Detailed Metrology Training Plan Including Competency-Based Credentialing ","authors":"J. Fuehne","doi":"10.51843/wsproceedings.2018.07","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.07","url":null,"abstract":"The Purdue Polytechnic Institute is one of ten colleges on the campus of Purdue University in West Lafayette, Indiana. Also included in the Institute is an outreach effort that includes ten locations spread throughout the state of Indiana to engage local communities and industries and to provide an alternative to the main campus for traditional and non-traditional students in those geographic areas. One of those areas is Columbus, Indiana, about an hour south of Indianapolis, and this paper relates experiences from that location. The Purdue Polytechnic Institute in Columbus, working together with corporate partner Cummins Inc., has developed a metrology training program that includes competency-based credentialing based on hands-on activities rather than a written test. This work includes specific details of the training program with activities required for competency-based credentialing. Many training programs include only a lecture/discussion format that usually include some written examination to demonstrate competency. In this plan, the Purdue Polytechnic Institute in Columbus utilizes metrology tools with targeted measurement artifacts, which may be 3-D printed, to facilitate learning and provide opportunities to demonstrate competency, leading to badges awarded by Purdue Polytechnic Institute for satisfactory performance. Criteria for earning the badges is also presented as well as tiered, layered approach to earning multiple badges. These metrology topics include dimensional metrology, surface finish metrology, and pressure metrology. Dimensional metrology is further layered for specific competencies involving different tools. Ultimately, this plan and effort will culminate in industry-accepted certifications based on earned badges and demonstrated competencies that are recognized throughout the manufacturing and measurement industries.","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130765910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.09
P. Abbott
The unit of mass has been realized by the International Prototype Kilogram (IPK) for over 130 years. This will change very soon. The revision of the International System of Units (SI) that will take effect on May 20, 2019 will fundamentally change the way the United States mass scale is realized by NIST at the one kilogram level and below. For example, below 50 mg, very precise measurements of capacitance gradient by the NIST Electrostatic Force Balance (EFB) will extend the lower end of the NIST mass scale to 100 micrograms or less and improve uncertainties by a factor of ten over what they are now, all while eliminating laborious work-downs from one kilogram standards. Between 100 g and one kilogram, the NIST-4 Kibble balance will realize mass from quantum-based electrical and mechanical power measurements. Mass transfer between the vacuum environment of the Kibble balance and the mass metrology performed in laboratory air pressure will be accomplished by a unique-to-NIST magnetic suspension-based mass comparator that will allow a test mass to be directly calibrated against an artifact whose mass has been determined by the Kibble balance. When considered in its entirety, the NIST mass scale under the revised SI will be easier to realize, easier to maintain, and have equal or smaller uncertainties that the mass scale that is traceable to the IPK. This presentation will illustrate how the NIST mass scale at one kilogram and below is constructed using the new instruments described above. An uncertainty budget covering the range from 1 kilogram to 100 micrograms will be given and the techniques that are used for mass dissemination in this range will be described.
{"title":"Mass Calibration at NIST in the Revised SI","authors":"P. Abbott","doi":"10.51843/wsproceedings.2018.09","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.09","url":null,"abstract":"The unit of mass has been realized by the International Prototype Kilogram (IPK) for over 130 years. This will change very soon. The revision of the International System of Units (SI) that will take effect on May 20, 2019 will fundamentally change the way the United States mass scale is realized by NIST at the one kilogram level and below. For example, below 50 mg, very precise measurements of capacitance gradient by the NIST Electrostatic Force Balance (EFB) will extend the lower end of the NIST mass scale to 100 micrograms or less and improve uncertainties by a factor of ten over what they are now, all while eliminating laborious work-downs from one kilogram standards. Between 100 g and one kilogram, the NIST-4 Kibble balance will realize mass from quantum-based electrical and mechanical power measurements. Mass transfer between the vacuum environment of the Kibble balance and the mass metrology performed in laboratory air pressure will be accomplished by a unique-to-NIST magnetic suspension-based mass comparator that will allow a test mass to be directly calibrated against an artifact whose mass has been determined by the Kibble balance. When considered in its entirety, the NIST mass scale under the revised SI will be easier to realize, easier to maintain, and have equal or smaller uncertainties that the mass scale that is traceable to the IPK. This presentation will illustrate how the NIST mass scale at one kilogram and below is constructed using the new instruments described above. An uncertainty budget covering the range from 1 kilogram to 100 micrograms will be given and the techniques that are used for mass dissemination in this range will be described.","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131281040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.08
J. Salsbury
A new American standard for digital, dial, and vernier calipers, ASME B89.1.14, was approved by the ASME B89 dimensional metrology standards committee in 2017, and final publication of the standard is expected in 2018. The purpose of this paper is to introduce the new standard and discuss some of the key developments. In particular, the standard includes default specifications and calibration test methods that will have a major impact to calibration services. This paper will review the history of the development of the standard and discuss all the major sections of the standard, including specifications, rated operating conditions, test methods, conformance decision rules, and measurement uncertainty. The relationship between ASME B89.1.14 and the international standard for calipers, ISO 13385-11, will also be discussed.
{"title":"The New American Standard for Digital, Dial, and Vernier Calipers","authors":"J. Salsbury","doi":"10.51843/wsproceedings.2018.08","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.08","url":null,"abstract":"A new American standard for digital, dial, and vernier calipers, ASME B89.1.14, was approved by the ASME B89 dimensional metrology standards committee in 2017, and final publication of the standard is expected in 2018. The purpose of this paper is to introduce the new standard and discuss some of the key developments. In particular, the standard includes default specifications and calibration test methods that will have a major impact to calibration services. This paper will review the history of the development of the standard and discuss all the major sections of the standard, including specifications, rated operating conditions, test methods, conformance decision rules, and measurement uncertainty. The relationship between ASME B89.1.14 and the international standard for calipers, ISO 13385-11, will also be discussed.","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134089654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.25
Mike Imholte
During the process of verifying K type thermocouples at high temperatures, the sheath turns gray or breaks down and flakes off. This creates a risk of contaminants and damage to product in a vacuum braze furnace. The cost of recertifying the thermocouples and cleaning of the furnace block when a thermocouple sheath breaks down is high. After working through this process for many years, I came up with a new furnace setup that reduces the potential for contamination of product. This paper will explain the process, verification station set up, tools and materials used to reduce oxidization of the sheath material. We have updated from an inconel isotheral block furnace to an alumina isotheral block furnace. This eliminates the contamination to the reference PRT being it also has an alumina sheath. The why is when an alumina sheath is contaminated with inconel the OEM will not calibrate the PRT because of possible contamination to the silver fixed point cell. The automation improvement has reduced cost in labor and down time.
{"title":"Oxidization, Contamination, and Automation for High Temperature Verification of Thermocouples","authors":"Mike Imholte","doi":"10.51843/wsproceedings.2018.25","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.25","url":null,"abstract":"During the process of verifying K type thermocouples at high temperatures, the sheath turns gray or breaks down and flakes off. This creates a risk of contaminants and damage to product in a vacuum braze furnace. The cost of recertifying the thermocouples and cleaning of the furnace block when a thermocouple sheath breaks down is high. After working through this process for many years, I came up with a new furnace setup that reduces the potential for contamination of product. This paper will explain the process, verification station set up, tools and materials used to reduce oxidization of the sheath material. We have updated from an inconel isotheral block furnace to an alumina isotheral block furnace. This eliminates the contamination to the reference PRT being it also has an alumina sheath. The why is when an alumina sheath is contaminated with inconel the OEM will not calibrate the PRT because of possible contamination to the silver fixed point cell. The automation improvement has reduced cost in labor and down time.","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131950574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.20
H. Zumbrun
There are several labs operating throughout the world, which does not follow a designated guideline for calculating measurement uncertainty for force calibrations done in accordance with the ASTM E74 standard. Realizing the need for a guidance document, Morehouse decided to draft this document explaining how to calculate measurement uncertainty and how uncertainty propagation for force calibration systems works. The document examines uncertainty contributors for different tiers in the calibration hierarchy. We start with tier one laboratories using primary standards which are dead weight machines and work through the uncertainty propagation through tier two or secondary laboratories and then tier three laboratories. Calibrations, repeatability studies, and other tests were performed at each tier using different types of force calibration equipment. The paper follows the uncertainty progression and answers a question of what type of calibration standard and Calibration and Measurement Capability (CMC) is needed to achieve a specific Calibration and Measurement Capability at the next tier. Through examining the various uncertainty contributors we arrive at a conclusion that several force scopes may not be realistic in their CMC claims which means they may not be able to make statements of conformance. The testing proved the importance of the reference standard in relation to overall expanded uncertainty. Deadweight primary standards are predictably the best possible reference standard. A laboratory using secondary standards—those standards calibrated by deadweight—can achieve CMC’s as low as 0.02 % of applied force if they are using several standards. Nonetheless, the downside of using several standards is that this method involves standards to be changed at least once during the calibration which often further impacts test results. Failing to account for all the uncertainty contributors at any tier and not calculating Calibration and Measurement Capability properly will influence the Unit Under Test (UUT) in several ways resulting in lower combined uncertainties and raising measurement risk levels on all instruments in the entire measurement chain.
{"title":"Uncertainty Propogation for Force Calibration Systems","authors":"H. Zumbrun","doi":"10.51843/wsproceedings.2018.20","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.20","url":null,"abstract":"There are several labs operating throughout the world, which does not follow a designated guideline for calculating measurement uncertainty for force calibrations done in accordance with the ASTM E74 standard. Realizing the need for a guidance document, Morehouse decided to draft this document explaining how to calculate measurement uncertainty and how uncertainty propagation for force calibration systems works. The document examines uncertainty contributors for different tiers in the calibration hierarchy. We start with tier one laboratories using primary standards which are dead weight machines and work through the uncertainty propagation through tier two or secondary laboratories and then tier three laboratories. Calibrations, repeatability studies, and other tests were performed at each tier using different types of force calibration equipment. The paper follows the uncertainty progression and answers a question of what type of calibration standard and Calibration and Measurement Capability (CMC) is needed to achieve a specific Calibration and Measurement Capability at the next tier. Through examining the various uncertainty contributors we arrive at a conclusion that several force scopes may not be realistic in their CMC claims which means they may not be able to make statements of conformance. The testing proved the importance of the reference standard in relation to overall expanded uncertainty. Deadweight primary standards are predictably the best possible reference standard. A laboratory using secondary standards—those standards calibrated by deadweight—can achieve CMC’s as low as 0.02 % of applied force if they are using several standards. Nonetheless, the downside of using several standards is that this method involves standards to be changed at least once during the calibration which often further impacts test results. Failing to account for all the uncertainty contributors at any tier and not calculating Calibration and Measurement Capability properly will influence the Unit Under Test (UUT) in several ways resulting in lower combined uncertainties and raising measurement risk levels on all instruments in the entire measurement chain.","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128425401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.35
Myles Gordon
It is not every day you have to opportunity to be both Metrologist and fire fighter. In our laboratory we were testing a specific temperature measuring device that utilized a lithium battery for power. During the testing in a liquid salt bath, the lithium battery did not take to the higher temperatures and effectively exploded. When it did, it caught the liquefied salt on fire. We had to jump into action very quickly to avoid a major disaster to our temperature lab and beyond. Consequently, this event prompted us to look our methodology for testing temperature measurement devices as a matter of safety and accuracy. Having the proper immersion depth is an important factor in obtaining an accurate measurement. However, certain parts of the device being exposed to excessive will lead to catastrophic failures. How do we safely test temperature measure devices with sacrificing quality?
{"title":"How to Put Out a Fire in a Liquid Salt Bath: Dealing with the Temperature Problems with Lithium Batteries","authors":"Myles Gordon","doi":"10.51843/wsproceedings.2018.35","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.35","url":null,"abstract":"It is not every day you have to opportunity to be both Metrologist and fire fighter. In our laboratory we were testing a specific temperature measuring device that utilized a lithium battery for power. During the testing in a liquid salt bath, the lithium battery did not take to the higher temperatures and effectively exploded. When it did, it caught the liquefied salt on fire. We had to jump into action very quickly to avoid a major disaster to our temperature lab and beyond. Consequently, this event prompted us to look our methodology for testing temperature measurement devices as a matter of safety and accuracy. Having the proper immersion depth is an important factor in obtaining an accurate measurement. However, certain parts of the device being exposed to excessive will lead to catastrophic failures. How do we safely test temperature measure devices with sacrificing quality?","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115647518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.38
G. Mihm
ISO/IEC 17025:2017 will be published by end of 2017. New requirement of ISO/IEC 17025:2017 e.g. is the statement of conformity. It is expected that most of the customers sending in test & measurement equipment for calibration ask for the statement of conformity. If the calibration order does not contain the technical specification of the item; the calibration lab has to deal with the customer to receive the specification required, and the calibration lab will send back with the price quotation the specification of a routine calibration. As ISO/IEC 17025:20177 does not require the print out of the calibration certificate, but needs to be signed, an electronic signature within an unchangeable electronic document has to fulfill all of the requirements of ISO/IEC 17025:2017. German armed Forces with NATO partners developed the standard ALogP-33.1 and the national defense standard VG 96910, which are in line with ISO 17025:2017. Statement of conformity should be in accordance with ILAC-G8:2009-03. The presentation will show the concept of this standard, the way of setting up technical specifications (according to ISO 10012 with metrological confirmation) and also discuss problems that arose in getting the standard into service.
{"title":"ISO 17025:2017: Design of the New Calibration Certificate","authors":"G. Mihm","doi":"10.51843/wsproceedings.2018.38","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.38","url":null,"abstract":"ISO/IEC 17025:2017 will be published by end of 2017. New requirement of ISO/IEC 17025:2017 e.g. is the statement of conformity. It is expected that most of the customers sending in test & measurement equipment for calibration ask for the statement of conformity. If the calibration order does not contain the technical specification of the item; the calibration lab has to deal with the customer to receive the specification required, and the calibration lab will send back with the price quotation the specification of a routine calibration. As ISO/IEC 17025:20177 does not require the print out of the calibration certificate, but needs to be signed, an electronic signature within an unchangeable electronic document has to fulfill all of the requirements of ISO/IEC 17025:2017. German armed Forces with NATO partners developed the standard ALogP-33.1 and the national defense standard VG 96910, which are in line with ISO 17025:2017. Statement of conformity should be in accordance with ILAC-G8:2009-03. The presentation will show the concept of this standard, the way of setting up technical specifications (according to ISO 10012 with metrological confirmation) and also discuss problems that arose in getting the standard into service.","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114736068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.04
B. Djokic
Rogowski coils (RCs) are widely used for measurements of high AC currents, transient currents and impulse currents. In AC resistance welding, they are used as current sensing coils (CSCs) in conjunction with weld-current meters/monitors (WCMs) for monitoring/controlling the weld currents, and thus ensuring the quality of welds. The CSCs are calibrated stand-alone or with WCMs at high pulsed currents at conditions close to those encountered in the field. These ´gated’ sinusoidal currents with variable angle of conduction deviate from sinusoidal waveform, and their harmonic content is large. This requires high sampling rate and integration, which affects negatively measurement uncertainty. In spite of the CT core-saturation, size, weight and cost constraints for measurements at large currents, they are used as reference devices in the calibrations of RCs at steady-state AC currents. A special electronically-enhanced CT was developed for the calibration of RCs in a copper coaxial cage at high pulsed currents of up to 35 kA. The implementation of this CT as the reference in a calibration system for Rogowski coils at high pulsed currents, which requires no integration, will be discussed in the paper, including traceability to SI units. Preliminary estimates of the measurement uncertainty will be given.
{"title":"Use of Current Transformers in Calibrations of Rogowski Coils at High Pulsed Currents","authors":"B. Djokic","doi":"10.51843/wsproceedings.2018.04","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.04","url":null,"abstract":"Rogowski coils (RCs) are widely used for measurements of high AC currents, transient currents and impulse currents. In AC resistance welding, they are used as current sensing coils (CSCs) in conjunction with weld-current meters/monitors (WCMs) for monitoring/controlling the weld currents, and thus ensuring the quality of welds. The CSCs are calibrated stand-alone or with WCMs at high pulsed currents at conditions close to those encountered in the field. These ´gated’ sinusoidal currents with variable angle of conduction deviate from sinusoidal waveform, and their harmonic content is large. This requires high sampling rate and integration, which affects negatively measurement uncertainty. In spite of the CT core-saturation, size, weight and cost constraints for measurements at large currents, they are used as reference devices in the calibrations of RCs at steady-state AC currents. A special electronically-enhanced CT was developed for the calibration of RCs in a copper coaxial cage at high pulsed currents of up to 35 kA. The implementation of this CT as the reference in a calibration system for Rogowski coils at high pulsed currents, which requires no integration, will be discussed in the paper, including traceability to SI units. Preliminary estimates of the measurement uncertainty will be given.","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131240553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.51843/wsproceedings.2018.40
C. Hung
According to ISO/IEC 17043:2010, the definition of proficiency testing is evaluation of participant performance against pre-established criteria by means of interlaboratory comparisons. Thus pre-established criteria has significant impact on the evaluation of participant performance, in which assigned value attributed to a particular property of a proficiency test item and its standard deviation for proficiency assessment played the key role in the evaluation criteria. In order to understand the gauge block calibration capacity of the domestic laboratories in Taiwan, the Center for Measurement Standards / Industrial Technology Research Institute (CMS/ITRI) held and completed a gauge block calibration proficiency testing in 2016. In this proficiency testing, CMS used the calibration results from National Measurement Laboratory (NML) to determine the assigned value and its expanded uncertainty which were used to calculate the |En| values. In addition, according to ISO/IEC 13528:2015, the assigned value and its standard uncertainty can be determined according to the type and purpose of the proficiency testing scheme, including using the results from one laboratory, consensus values from participant results, etc. In order to explore the impact of choosing different methods to determine the assigned value and its expanded uncertainty for proficiency testing results, CMS recalculated the |En| values by using different assigned value determination method after the end of this proficiency testing. Thus, the narrative of this paper contains not only results of this gauge block calibration proficiency testing but also results of using different assigned value determination method to recalculate participant performance statistics.
{"title":"Analysis of Different Assigned Value Determination Methods on Gauge Block Calibration Proficiency Testing","authors":"C. Hung","doi":"10.51843/wsproceedings.2018.40","DOIUrl":"https://doi.org/10.51843/wsproceedings.2018.40","url":null,"abstract":"According to ISO/IEC 17043:2010, the definition of proficiency testing is evaluation of participant performance against pre-established criteria by means of interlaboratory comparisons. Thus pre-established criteria has significant impact on the evaluation of participant performance, in which assigned value attributed to a particular property of a proficiency test item and its standard deviation for proficiency assessment played the key role in the evaluation criteria. In order to understand the gauge block calibration capacity of the domestic laboratories in Taiwan, the Center for Measurement Standards / Industrial Technology Research Institute (CMS/ITRI) held and completed a gauge block calibration proficiency testing in 2016. In this proficiency testing, CMS used the calibration results from National Measurement Laboratory (NML) to determine the assigned value and its expanded uncertainty which were used to calculate the |En| values. In addition, according to ISO/IEC 13528:2015, the assigned value and its standard uncertainty can be determined according to the type and purpose of the proficiency testing scheme, including using the results from one laboratory, consensus values from participant results, etc. In order to explore the impact of choosing different methods to determine the assigned value and its expanded uncertainty for proficiency testing results, CMS recalculated the |En| values by using different assigned value determination method after the end of this proficiency testing. Thus, the narrative of this paper contains not only results of this gauge block calibration proficiency testing but also results of using different assigned value determination method to recalculate participant performance statistics.","PeriodicalId":120844,"journal":{"name":"NCSL International Workshop & Symposium Conference Proceedings 2018","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129416620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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