Several grades of silver 10-wt.% tin oxide with tellurium oxide additions have been prepared by a powder metallurgy process involving powder mixing, compression, sintering, and second compression to maximum density. The contact parts have been submitted to different electrical tests. After 20000 openings of a 100-A circuit, the erosion loss of 1% tellurium oxide doped silver tin oxide is 13.2 mg compared with 50 mg for internally oxidized silver cadmium oxide. Another test with AC 3 conditions at 100 A of current at opening and 600 A at closing shows that 1% to 1.5% tellurium oxide doped silver/tin oxide has a low temperature rise and very low welding forces compared with nondoped silver tin oxide. 2.0 and 3.0% tellurium oxide shows the same behavior in a 1050-A making current test. The erosion rate is not increased with tellurium oxide additions. The low welding forces result in an improved making capacity in contactor applications.<>
{"title":"A new doped silver tin oxide with improved electrical behaviour","authors":"C. Lambert, D. Weber, S. Coupez, J.P. Guerlet","doi":"10.1109/HOLM.1989.77919","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77919","url":null,"abstract":"Several grades of silver 10-wt.% tin oxide with tellurium oxide additions have been prepared by a powder metallurgy process involving powder mixing, compression, sintering, and second compression to maximum density. The contact parts have been submitted to different electrical tests. After 20000 openings of a 100-A circuit, the erosion loss of 1% tellurium oxide doped silver tin oxide is 13.2 mg compared with 50 mg for internally oxidized silver cadmium oxide. Another test with AC 3 conditions at 100 A of current at opening and 600 A at closing shows that 1% to 1.5% tellurium oxide doped silver/tin oxide has a low temperature rise and very low welding forces compared with nondoped silver tin oxide. 2.0 and 3.0% tellurium oxide shows the same behavior in a 1050-A making current test. The erosion rate is not increased with tellurium oxide additions. The low welding forces result in an improved making capacity in contactor applications.<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125585373","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}
Surface films produced by natural aging mechanisms are primarily responsible for the failure of electrical contacts in the field. Some of the mechanisms of organic and inorganic film formation are reviewed. It is demonstrated that the sudden failure mode is entirely consistent with contemporary theories of film effects and asperity models of the contact interface. Reliability of the electrical contact is shown to be a function of materials, the operating environment, and interface motion. On the basis of the present understanding of film formation kinetics and typical asperity sizes, it is concluded that interfaces do not degrade by a simple asperity erosion process. However, film formation occurs in areas surrounding asperity peaks due to environmental ingress. It is proposed that this source of film, together with microscopic movement of the interface, can account for a major portion of the intermittent and hard contact failures related to surface films. These results strongly indicate that the disturbance/motion effects must be incorporated into laboratory qualification procedures. If they are not, typical results may grossly underestimate probable contact performance.<>
{"title":"Materials, environment, motion, and electrical contact failure mechanisms","authors":"W. Abbott","doi":"10.1109/HOLM.1989.77913","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77913","url":null,"abstract":"Surface films produced by natural aging mechanisms are primarily responsible for the failure of electrical contacts in the field. Some of the mechanisms of organic and inorganic film formation are reviewed. It is demonstrated that the sudden failure mode is entirely consistent with contemporary theories of film effects and asperity models of the contact interface. Reliability of the electrical contact is shown to be a function of materials, the operating environment, and interface motion. On the basis of the present understanding of film formation kinetics and typical asperity sizes, it is concluded that interfaces do not degrade by a simple asperity erosion process. However, film formation occurs in areas surrounding asperity peaks due to environmental ingress. It is proposed that this source of film, together with microscopic movement of the interface, can account for a major portion of the intermittent and hard contact failures related to surface films. These results strongly indicate that the disturbance/motion effects must be incorporated into laboratory qualification procedures. If they are not, typical results may grossly underestimate probable contact performance.<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128172864","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}
A technology assessment of new materials that may be useful in the future for interconnection devices, such as connectors, is presented. The work comprises two parts: characterization of Au- or Ag-plated Ni spheres in a silicon polymer matrix, and characterization of gold-capped Ni wires embedded in a silicone polymer matrix. In a silicone polymer matrix, embedded gold-plated metal wires or aligned gold-plated nickel spheres have the unique property of being electrically conductive in the Z-direction (thickness) while maintaining high insulation resistance in the X and Y directions. These materials can be used as an interface for anisotropic electric conduction between metallic elements. Contact resistance distributions as a function of probe area and geometry, load-displacement-resistance, stiffness, and mixed gas test are reported. The data relate to the evaluation of new materials and designs for interconnects in the 80 to 100 per inch range.<>
{"title":"Characterization of metal-in-elastomer connector contact material","authors":"C. Haque","doi":"10.1109/HOLM.1989.77930","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77930","url":null,"abstract":"A technology assessment of new materials that may be useful in the future for interconnection devices, such as connectors, is presented. The work comprises two parts: characterization of Au- or Ag-plated Ni spheres in a silicon polymer matrix, and characterization of gold-capped Ni wires embedded in a silicone polymer matrix. In a silicone polymer matrix, embedded gold-plated metal wires or aligned gold-plated nickel spheres have the unique property of being electrically conductive in the Z-direction (thickness) while maintaining high insulation resistance in the X and Y directions. These materials can be used as an interface for anisotropic electric conduction between metallic elements. Contact resistance distributions as a function of probe area and geometry, load-displacement-resistance, stiffness, and mixed gas test are reported. The data relate to the evaluation of new materials and designs for interconnects in the 80 to 100 per inch range.<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114938368","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}
Data taken from two separate programs designed to characterize and measure particulate content in industrial environments are presented and examined. This testing was undertaken to aid in understanding what is encountered by business machines installed in these environments. The method of collecting and analyzing the data obtained from a selection of industrial sites in the Chicago, Illinois area is presented. The application of data to the design and evaluation of a magnet sensor for use in these environments is illustrated. Settleable contamination was analyzed in six different manufacturing industries: heavy machinery, stainless steel sinks, motor vehicles, electrical connectors, and steel sheet metal stamping. The intent of the second sampling program was to monitor a diverse spectrum of industries with moderate-to-severe particulate environments. The particulate environment characterization covered five types of industry: steel, textiles, paper, railroads, and metal products manufacturers. Each site is listed with the sampling locations noted and quantitative and qualitative data tabulated for the locations.<>
{"title":"Settleable and airborne particles in industrial environments","authors":"R. Bayer, R. Ginsburg, R. Lasky","doi":"10.1109/HOLM.1989.77935","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77935","url":null,"abstract":"Data taken from two separate programs designed to characterize and measure particulate content in industrial environments are presented and examined. This testing was undertaken to aid in understanding what is encountered by business machines installed in these environments. The method of collecting and analyzing the data obtained from a selection of industrial sites in the Chicago, Illinois area is presented. The application of data to the design and evaluation of a magnet sensor for use in these environments is illustrated. Settleable contamination was analyzed in six different manufacturing industries: heavy machinery, stainless steel sinks, motor vehicles, electrical connectors, and steel sheet metal stamping. The intent of the second sampling program was to monitor a diverse spectrum of industries with moderate-to-severe particulate environments. The particulate environment characterization covered five types of industry: steel, textiles, paper, railroads, and metal products manufacturers. Each site is listed with the sampling locations noted and quantitative and qualitative data tabulated for the locations.<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"28 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113979177","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}
Summary form only given. Activities prior to tooling were considered, including: (1) product design FMEA (identification of critical product characteristics, identification of major product characteristics, determination and justification of specification limits, determination of appropriate gaging techniques, and raw material requirements); (2) process FMEA, which encompasses all primary processes such as stamping, molding, plating, and assembly. Also considered were tool qualification (first article requirements, process potential study requirements, gage potential requirements, and long-term process qualification); and quality requirements (Cpk requirements, deviation from target, and quality as produced and shipped evaluation).<>
{"title":"Advanced quality planning issues","authors":"C. Craig","doi":"10.1109/HOLM.1989.77926","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77926","url":null,"abstract":"Summary form only given. Activities prior to tooling were considered, including: (1) product design FMEA (identification of critical product characteristics, identification of major product characteristics, determination and justification of specification limits, determination of appropriate gaging techniques, and raw material requirements); (2) process FMEA, which encompasses all primary processes such as stamping, molding, plating, and assembly. Also considered were tool qualification (first article requirements, process potential study requirements, gage potential requirements, and long-term process qualification); and quality requirements (Cpk requirements, deviation from target, and quality as produced and shipped evaluation).<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126962314","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}
Contact erosion depends on both the duration and efficiency of interaction between arc and contacts. The arc motion in a magnetic field was recorded, and the material loss caused by arc erosion was weighed. The material loss related to 1 ms of arc interaction, called erodibility, was evaluated for the contact materials Ag/CdO and Ag/SnO/sub 2/. All tests were performed in one type of commercial contactor (rated current 110 A). The erodibility was determined for new and partly eroded contacted prestressed during life tests under AC 3 and AC 4 conditions according to IEC test specification 158-1. AC 4 erosion was mainly caused by break arcs, but the effect of make arcs was negligible, whereas AC 3 erosion was due to both break and make arcs. The latter were more effective in Ag/SnO/sub 2/ contacts. After AC 3 life tests the erodibility values determining the erosion of Ag/SnO/sub 2/ contacts at the site of arc formation were higher than those of Ag/CdO; after AC 4 life tests, however, there was hardly any difference between the erodibilities of the two materials.<>
{"title":"Erosion behaviour and 'erodibility' of Ag/CdO and Ag/SnO/sub 2/ contacts under AC 3 and AC 4 test conditions","authors":"H. Manhart, W. Rieder","doi":"10.1109/HOLM.1989.77905","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77905","url":null,"abstract":"Contact erosion depends on both the duration and efficiency of interaction between arc and contacts. The arc motion in a magnetic field was recorded, and the material loss caused by arc erosion was weighed. The material loss related to 1 ms of arc interaction, called erodibility, was evaluated for the contact materials Ag/CdO and Ag/SnO/sub 2/. All tests were performed in one type of commercial contactor (rated current 110 A). The erodibility was determined for new and partly eroded contacted prestressed during life tests under AC 3 and AC 4 conditions according to IEC test specification 158-1. AC 4 erosion was mainly caused by break arcs, but the effect of make arcs was negligible, whereas AC 3 erosion was due to both break and make arcs. The latter were more effective in Ag/SnO/sub 2/ contacts. After AC 3 life tests the erodibility values determining the erosion of Ag/SnO/sub 2/ contacts at the site of arc formation were higher than those of Ag/CdO; after AC 4 life tests, however, there was hardly any difference between the erodibilities of the two materials.<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121982395","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}
A study was undertaken to develop a mathematical model that correlates gold-plated card-edge connector reliability with contact design parameters in office-type corrosive gas and dust environments. The first phase of the study focused on connector behavior in an office dust environment. The authors describe the experiments, the statistical modeling approach, and the resultant mathematical model. This led to developing a novel expression for contact failure as a function of normal force and lubrication levels. Increasing contact normal force is found to decrease failure, whereas increasing lubrication levels (in the office dust environment) increase failure.<>
{"title":"A mathematical model relating card-edge connectors failure to normal force and lubrication in office dust environment","authors":"M. Singer, V. Florescu","doi":"10.1109/HOLM.1989.77929","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77929","url":null,"abstract":"A study was undertaken to develop a mathematical model that correlates gold-plated card-edge connector reliability with contact design parameters in office-type corrosive gas and dust environments. The first phase of the study focused on connector behavior in an office dust environment. The authors describe the experiments, the statistical modeling approach, and the resultant mathematical model. This led to developing a novel expression for contact failure as a function of normal force and lubrication levels. Increasing contact normal force is found to decrease failure, whereas increasing lubrication levels (in the office dust environment) increase failure.<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125442549","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}
Summary form only given. Xerox requirements for reliable connector contacts were addressed. The thrust of the activity is a cooperative technical effort with the vendor. From the information on the program's machine environment, class, lifecycle, PWBA assembly processes, and cable harness cost targets (robotics implication), the qualification requirements were defined. Xerox start-up protection activities were also considered. These activities are undertaken to ensure that the quality targets (in this case, the connector contacts) are met before the product passes to the manufacturing phase. Activities in three program phases (design, prototype, and early manufacturing) were discussed. In each phase, specific activities are performed to measure the performance of the interconnect system. The role of closed-loop corrective action and history file was discussed in terms of negotiated quality targets with the vendor(s).<>
{"title":"Requirements for reliable connector contacts","authors":"G. Bolger","doi":"10.1109/HOLM.1989.77925","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77925","url":null,"abstract":"Summary form only given. Xerox requirements for reliable connector contacts were addressed. The thrust of the activity is a cooperative technical effort with the vendor. From the information on the program's machine environment, class, lifecycle, PWBA assembly processes, and cable harness cost targets (robotics implication), the qualification requirements were defined. Xerox start-up protection activities were also considered. These activities are undertaken to ensure that the quality targets (in this case, the connector contacts) are met before the product passes to the manufacturing phase. Activities in three program phases (design, prototype, and early manufacturing) were discussed. In each phase, specific activities are performed to measure the performance of the interconnect system. The role of closed-loop corrective action and history file was discussed in terms of negotiated quality targets with the vendor(s).<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129549590","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}
The extinction or reignition of high-frequency transients plays an important role in the generation of voltage surges. Investigations with currents of several hundred amperes peak and current frequencies from 100 kHz up to 1 MHz were made to examine the reignition behavior of short vacuum gaps using different contact materials. The experiments were carried out in an UHV (ultrahigh vacuum) test chamber connected to an LC test circuit with voltages in the 10-kV range. The statistical distribution of the reignition voltage after current zero of HF vacuum arcs yields two probable reignition mechanisms, the cold gap behavior and the plasma-influenced reignition. The reignition tendency increases with rising di/dt and rising current frequency. The reignition voltages of the examined contact materials increase in the sequence: OFHC Cu, Cr, Cu/Cr 75/25.<>
{"title":"The influence of circuit parameters and contact materials on the reignition of high frequency vacuum arcs","authors":"M. Lindmayer, Ernst-Dieter Wilkening","doi":"10.1109/HOLM.1989.77945","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77945","url":null,"abstract":"The extinction or reignition of high-frequency transients plays an important role in the generation of voltage surges. Investigations with currents of several hundred amperes peak and current frequencies from 100 kHz up to 1 MHz were made to examine the reignition behavior of short vacuum gaps using different contact materials. The experiments were carried out in an UHV (ultrahigh vacuum) test chamber connected to an LC test circuit with voltages in the 10-kV range. The statistical distribution of the reignition voltage after current zero of HF vacuum arcs yields two probable reignition mechanisms, the cold gap behavior and the plasma-influenced reignition. The reignition tendency increases with rising di/dt and rising current frequency. The reignition voltages of the examined contact materials increase in the sequence: OFHC Cu, Cr, Cu/Cr 75/25.<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126346655","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}
Experiments were conducted on the corrosion of materials in a broad variety of single-component and multicomponent flowing mixed gas environments. One purpose of the experiments was to document in a consistent manner the corrosion rates and effect which can be expected for different gas mixtures. A second objective was to demonstrate the importance of standardized control materials for documenting environmental tests. The results confirm that flowing mixed gas environments based upon the use of the sulfide-chloride synergisms produce relevant corrosion with useful accelerator factors. Nonchloride environments were found to be relatively high. Two materials were demonstrated to be useful for documenting the conditions actually obtained during environmental tests. These are copper and porous gold. Neither alone can present an adequate descriptor of the test conditions actually achieved. Used together, however, they can provide a sensitive indicator of corrosion rates and mechanisms.<>
{"title":"The corrosion of copper and porous gold in flowing mixed gas environments","authors":"W. Abbott","doi":"10.1109/HOLM.1989.77933","DOIUrl":"https://doi.org/10.1109/HOLM.1989.77933","url":null,"abstract":"Experiments were conducted on the corrosion of materials in a broad variety of single-component and multicomponent flowing mixed gas environments. One purpose of the experiments was to document in a consistent manner the corrosion rates and effect which can be expected for different gas mixtures. A second objective was to demonstrate the importance of standardized control materials for documenting environmental tests. The results confirm that flowing mixed gas environments based upon the use of the sulfide-chloride synergisms produce relevant corrosion with useful accelerator factors. Nonchloride environments were found to be relatively high. Two materials were demonstrated to be useful for documenting the conditions actually obtained during environmental tests. These are copper and porous gold. Neither alone can present an adequate descriptor of the test conditions actually achieved. Used together, however, they can provide a sensitive indicator of corrosion rates and mechanisms.<<ETX>>","PeriodicalId":441734,"journal":{"name":"Proceedings of the Thirty Fifth Meeting of the IEEE Holm Conference on Electrical Contacts","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133967206","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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