Pub Date : 2007-09-24DOI: 10.1109/HOLM.2007.4318219
E. Carvou, N. Ben Jemaa
It is well known that vibrations of contact interfaces are the main cause of contact degradation by the so called fretting corrosion phenomena. In fact the process of generated particles by mechanical wear produce either the increase of contact voltage accompanied with rapid fluctuations. The main objective of this work is to examine the electrical behaviour of contact interface under vibration and characterize theses fluctuations during the fretting. A single point contact is submitted to high number of vibrations (103 to 107) at 100 Hz with an amplitude of 50 mum. The contact is in a resistive circuit supplied by 14 V and 10 A. The contact voltage is acquired with fast sampling oscilloscope and fluctuations are analysed by real time FFT module. We have found that, depending on the degradation stage, the apparition of these fluctuations is attributed to electro-mechanical phenomena. Some slow fluctuations are well correlated to vibration period while the rapid ones are linked to electrical conduction perturbation in granular interface by movement. Furthermore, the self-heating by such high contact voltage at high current levels is examined.
{"title":"Time and Level Analysis of Contact Voltage Intermittences Induced by Fretting in Power Connector","authors":"E. Carvou, N. Ben Jemaa","doi":"10.1109/HOLM.2007.4318219","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318219","url":null,"abstract":"It is well known that vibrations of contact interfaces are the main cause of contact degradation by the so called fretting corrosion phenomena. In fact the process of generated particles by mechanical wear produce either the increase of contact voltage accompanied with rapid fluctuations. The main objective of this work is to examine the electrical behaviour of contact interface under vibration and characterize theses fluctuations during the fretting. A single point contact is submitted to high number of vibrations (103 to 107) at 100 Hz with an amplitude of 50 mum. The contact is in a resistive circuit supplied by 14 V and 10 A. The contact voltage is acquired with fast sampling oscilloscope and fluctuations are analysed by real time FFT module. We have found that, depending on the degradation stage, the apparition of these fluctuations is attributed to electro-mechanical phenomena. Some slow fluctuations are well correlated to vibration period while the rapid ones are linked to electrical conduction perturbation in granular interface by movement. Furthermore, the self-heating by such high contact voltage at high current levels is examined.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90439861","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 : 2007-09-24DOI: 10.1109/HOLM.2007.4318188
R. Malucci, A. Panella
The resistance and capacitance of a typical multi-point contact interface has been used to assess the impact on high frequency signal integrity. In the past it was shown how fully degraded interfaces can still provide acceptable performance for high data rate signal transfers. In the case of fully degraded contacts, signals were shown to transfer by capacitive coupling and wave propagation. This paper focuses on the critical parameters of a capacitive coupled interface. Moreover, the physics of the contact interface is related to contacts that rely on capacitive (as opposed to metallic) coupling and electronic tunneling. These results help define the physics and design requirements for capacitive coupling. In addition, critical performance parameters such as real contact area, film thickness and the nature of dielectric films are defined for high frequency signal propagation. This paper provides a contrast between the requirements for high frequency signal transfer using capacitive coupling and electron tunneling versus traditional metallic contact.
{"title":"Contact Physics of Capacitive Interconnects","authors":"R. Malucci, A. Panella","doi":"10.1109/HOLM.2007.4318188","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318188","url":null,"abstract":"The resistance and capacitance of a typical multi-point contact interface has been used to assess the impact on high frequency signal integrity. In the past it was shown how fully degraded interfaces can still provide acceptable performance for high data rate signal transfers. In the case of fully degraded contacts, signals were shown to transfer by capacitive coupling and wave propagation. This paper focuses on the critical parameters of a capacitive coupled interface. Moreover, the physics of the contact interface is related to contacts that rely on capacitive (as opposed to metallic) coupling and electronic tunneling. These results help define the physics and design requirements for capacitive coupling. In addition, critical performance parameters such as real contact area, film thickness and the nature of dielectric films are defined for high frequency signal propagation. This paper provides a contrast between the requirements for high frequency signal transfer using capacitive coupling and electron tunneling versus traditional metallic contact.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80423848","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 : 2007-09-24DOI: 10.1109/HOLM.2007.4318193
Degui Chen, Zhipeng Li, Xingwen Li, Liang Ji, Zhengxiang Song
Pressure rise of the gas due to high current arc in the arc chamber of molded case circuit breaker (MCCB) may accelerate the arc movement and improve the corresponding interruption performance. However, this pressure rise may result in a heavy stress on the enclosure of the arc chamber. The paper is devoted to calculate the pressure rise and analyze its characteristics. Based on thermodynamics and ideal gas law, the pressure rise variation with time could be calculated taking into account the influence of arc current, venting size, splitter plates and gassing material. Relevant experiments also were carried out to verify the proposed calculation method. It demonstrates that the pressure rise in the arc chamber will be increased with the higher arc current, less venting and the existence of gassing material.
{"title":"Simulation of Pressure Rise in Arc Chamber of MCCB During its Interruption Process","authors":"Degui Chen, Zhipeng Li, Xingwen Li, Liang Ji, Zhengxiang Song","doi":"10.1109/HOLM.2007.4318193","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318193","url":null,"abstract":"Pressure rise of the gas due to high current arc in the arc chamber of molded case circuit breaker (MCCB) may accelerate the arc movement and improve the corresponding interruption performance. However, this pressure rise may result in a heavy stress on the enclosure of the arc chamber. The paper is devoted to calculate the pressure rise and analyze its characteristics. Based on thermodynamics and ideal gas law, the pressure rise variation with time could be calculated taking into account the influence of arc current, venting size, splitter plates and gassing material. Relevant experiments also were carried out to verify the proposed calculation method. It demonstrates that the pressure rise in the arc chamber will be increased with the higher arc current, less venting and the existence of gassing material.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81691997","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 : 2007-09-24DOI: 10.1109/HOLM.2007.4318212
E. M. Yunus, J. McBride, S. Spearing
Carbon-nanotube (CNT) coated surfaces are investigated to determine the electrical contact performance under low force conditions. The surfaces under investigation are multi-walled CNTs formed on a silicon substrate and coated with an Au film. These planar surfaces are mated with a hemispherical Au plated probe mounted in a nano-indentation apparatus. The maximum contact force used is 1 mN. The contact resistance of these surfaces is investigated as a function of the applied force and is also studied under repeated loading cycles. The surfaces are compared with a reference Au-Au contact under the same experimental conditions and the results compared to established contact theory. The results show that the multi-walled CNT surface provides a stable contact resistance, but that the performance could be improved further with the application of single-walled CNT coatings. This initial study shows the potential for the application of CNT surfaces as an interface in low force electrical contact applications.
{"title":"The Relationship between Contact Resistance and Contact Force on Au coated Carbon Nanotube surfaces","authors":"E. M. Yunus, J. McBride, S. Spearing","doi":"10.1109/HOLM.2007.4318212","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318212","url":null,"abstract":"Carbon-nanotube (CNT) coated surfaces are investigated to determine the electrical contact performance under low force conditions. The surfaces under investigation are multi-walled CNTs formed on a silicon substrate and coated with an Au film. These planar surfaces are mated with a hemispherical Au plated probe mounted in a nano-indentation apparatus. The maximum contact force used is 1 mN. The contact resistance of these surfaces is investigated as a function of the applied force and is also studied under repeated loading cycles. The surfaces are compared with a reference Au-Au contact under the same experimental conditions and the results compared to established contact theory. The results show that the multi-walled CNT surface provides a stable contact resistance, but that the performance could be improved further with the application of single-walled CNT coatings. This initial study shows the potential for the application of CNT surfaces as an interface in low force electrical contact applications.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82675266","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 : 2007-09-24DOI: 10.1109/HOLM.2007.4318209
K. Kataoka, K. Inoue, T. Itoh, T. Suga
We report on the contact process utilizing fritting phenomena between Al electrode and probes made of tin or tin gold alloy. The contact method with low contact force on Al electrodes is required for test probing of LSI for the next generation. The test probes made of tungsten or nickel are suitable for making contact with mechanical breaking of aluminum oxide. However, when these hard probes are used for fritting contact process, aluminum debris adheres to the probes and the contact failure occurs after several hundred contacts. In order to solve this problem, the low-force contact properties of soft probes are investigated in this paper. It was found that the mixture or alloy of tin and aluminum is generated in the contact area and remains on both the probe and the aluminum electrode after breaking the contact. Moreover, the probe made of tin-gold alloy is found to accumulate less aluminum debris and the contact resistance remains lower than 10 Omega after 1,000 contacts.
{"title":"Fritting Contact Using SnAu probe","authors":"K. Kataoka, K. Inoue, T. Itoh, T. Suga","doi":"10.1109/HOLM.2007.4318209","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318209","url":null,"abstract":"We report on the contact process utilizing fritting phenomena between Al electrode and probes made of tin or tin gold alloy. The contact method with low contact force on Al electrodes is required for test probing of LSI for the next generation. The test probes made of tungsten or nickel are suitable for making contact with mechanical breaking of aluminum oxide. However, when these hard probes are used for fritting contact process, aluminum debris adheres to the probes and the contact failure occurs after several hundred contacts. In order to solve this problem, the low-force contact properties of soft probes are investigated in this paper. It was found that the mixture or alloy of tin and aluminum is generated in the contact area and remains on both the probe and the aluminum electrode after breaking the contact. Moreover, the probe made of tin-gold alloy is found to accumulate less aluminum debris and the contact resistance remains lower than 10 Omega after 1,000 contacts.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85848956","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 : 2007-09-24DOI: 10.1109/HOLM.2007.4318218
N. Morita, T. Ueno, T. Otaka, M. Arata
In large turbine generators for thermal or nuclear power plants, such as 1000 MVA power plants, brush & collector ring sliding contact operation characteristics, where more than 5000 A field exciting current flows, are one of the most important problem for its reliability. In case of turbine generator collector ring, ring material is usually made of steel, as a view point of mechanical strength for high speed operation, such as 60 m/s, where brush contact characteristics for the steel ring have not been well known or have not been enough disclosed. Besides collector ring profile distortion which may cause brush seating operation difficulties, has to be allowed to some extent, due to mechanical structure of the turbine generator rotor & machining process feature. These mean that the suitable carbon brush grades for this purpose are limited, even though hundreds of carbon brush grades are supplied all over the world by brush manufacturers. In this paper, results of the carbon brush grades comparison test for evaluating dynamic operation characteristics by applying very high sliding speed condition & very high brush current density condition, are presented. As results of the test, it is clarified that in case of lower apparent density brushes and lower flexural strength brushes among the natural graphite grades, better dynamic operation characteristics are given.
{"title":"Comparison of Brush Dynamic Operation Characterisitics for Turbine Generator Steel Collector Ring","authors":"N. Morita, T. Ueno, T. Otaka, M. Arata","doi":"10.1109/HOLM.2007.4318218","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318218","url":null,"abstract":"In large turbine generators for thermal or nuclear power plants, such as 1000 MVA power plants, brush & collector ring sliding contact operation characteristics, where more than 5000 A field exciting current flows, are one of the most important problem for its reliability. In case of turbine generator collector ring, ring material is usually made of steel, as a view point of mechanical strength for high speed operation, such as 60 m/s, where brush contact characteristics for the steel ring have not been well known or have not been enough disclosed. Besides collector ring profile distortion which may cause brush seating operation difficulties, has to be allowed to some extent, due to mechanical structure of the turbine generator rotor & machining process feature. These mean that the suitable carbon brush grades for this purpose are limited, even though hundreds of carbon brush grades are supplied all over the world by brush manufacturers. In this paper, results of the carbon brush grades comparison test for evaluating dynamic operation characteristics by applying very high sliding speed condition & very high brush current density condition, are presented. As results of the test, it is clarified that in case of lower apparent density brushes and lower flexural strength brushes among the natural graphite grades, better dynamic operation characteristics are given.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78237292","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 : 2007-09-24DOI: 10.1109/HOLM.2007.4318216
T. Kobayashi, K. Sawa, K. Endo, G. Ou, H. Hagino
An electric sliding system is used to transfer electrical power or signal between a moving object and a stationary object. Long life time and improvement of contact reliability are required for electric sliding systems. Contact resistance and wear of sliding material are important factors. We have been investigating the sliding quality and the deterioration process of the system of Au plated slip-ring and Ag-Pd brush, which is used mainly in the chip-mounter, to get stable long life time. Through the three times previous tests, the lifetime is dependent on load current and others. However, the deterioration process is almost same, independent of long or short lifetime. When the Au and Ni plated layers are worn out, the base material of the ring, bronze is exposed and the surface starts to be oxidized. In this stage the contact resistance rapidly increases and then the lifetime is over. The lifetime is decided mainly by the surface wear rate. Further, in the third test, additional experimental results are presented, which are performed to clarify factors affecting the sliding lifetime. We got interesting results of about 6000 hours life corresponding to 144,000,000 rotations, which is the longest lifetime in our tests. In this test, we have the forth test which is intended to research the effect of lubricant and temperature of the surface on lifetime.
{"title":"A study of sliding characteristics of small-size slip-ring system for electric power supply","authors":"T. Kobayashi, K. Sawa, K. Endo, G. Ou, H. Hagino","doi":"10.1109/HOLM.2007.4318216","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318216","url":null,"abstract":"An electric sliding system is used to transfer electrical power or signal between a moving object and a stationary object. Long life time and improvement of contact reliability are required for electric sliding systems. Contact resistance and wear of sliding material are important factors. We have been investigating the sliding quality and the deterioration process of the system of Au plated slip-ring and Ag-Pd brush, which is used mainly in the chip-mounter, to get stable long life time. Through the three times previous tests, the lifetime is dependent on load current and others. However, the deterioration process is almost same, independent of long or short lifetime. When the Au and Ni plated layers are worn out, the base material of the ring, bronze is exposed and the surface starts to be oxidized. In this stage the contact resistance rapidly increases and then the lifetime is over. The lifetime is decided mainly by the surface wear rate. Further, in the third test, additional experimental results are presented, which are performed to clarify factors affecting the sliding lifetime. We got interesting results of about 6000 hours life corresponding to 144,000,000 rotations, which is the longest lifetime in our tests. In this test, we have the forth test which is intended to research the effect of lubricant and temperature of the surface on lifetime.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80728336","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 : 2007-09-24DOI: 10.1109/HOLM.2007.4318229
J. Sekikawa, T. Kubono
Break arcs occurring between electrical contacts are observed in DC42V resistive circuit using a high-speed camera. Materials of contact pairs are Ag or Ag/ZnO. The break current is 10A. Spectroscopic images are obtained using the high-speed camera with optical band pass filters. The filters are attached on the lens to observe only the Agl 521 nm or ZnI 481 nm spectrum images, respectively. The time evolutions of these images are discussed. The following results are obtained. For Ag/ZnO contacts, the intensity of the images of Ag spectrum line is almost same for the cases of the long and short arc-durations. On the other hand, the intensity of Zn spectrum line for the case of short arc-duration is higher than that of long arc-duration. These results show the existence of Ag rich layer on the contact surface for the case of long arc-duration and the higher evaporation rate of ZnO for the case of short arc-duration.
{"title":"Spectroscopic Imaging Observation of Break Arcs using a High-speed Camera","authors":"J. Sekikawa, T. Kubono","doi":"10.1109/HOLM.2007.4318229","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318229","url":null,"abstract":"Break arcs occurring between electrical contacts are observed in DC42V resistive circuit using a high-speed camera. Materials of contact pairs are Ag or Ag/ZnO. The break current is 10A. Spectroscopic images are obtained using the high-speed camera with optical band pass filters. The filters are attached on the lens to observe only the Agl 521 nm or ZnI 481 nm spectrum images, respectively. The time evolutions of these images are discussed. The following results are obtained. For Ag/ZnO contacts, the intensity of the images of Ag spectrum line is almost same for the cases of the long and short arc-durations. On the other hand, the intensity of Zn spectrum line for the case of short arc-duration is higher than that of long arc-duration. These results show the existence of Ag rich layer on the contact surface for the case of long arc-duration and the higher evaporation rate of ZnO for the case of short arc-duration.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81610860","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 : 2007-09-24DOI: 10.1109/HOLM.2007.4318199
B. Chudnovsky, V. Pavageau, M. Rapeaux, A. Zolfaghari, P. Bardollet
This paper presents a thermal study of aluminum with tin plating deposited on Al using three different types of tin plating using various cyanide and non-cyanide processes. We determined the quality of plating before and after it was exposed to the temperature of 150degC in air for up to eight weeks using multiple testing techniques, such as adhesion test, thermal shock test, SEM techniques, EDS X-ray analysis, and thickness measurements. We determined that after aging test tin plating shows aging related cracks, voids and separation appearing at the plating interfaces although in different concentration and progression rates depending on plating technique. All types of plating demonstrated deteriorated plating adhesion. Accelerated thermal aging tests at 150degC discriminate plating types. Aged samples exhibit medium to poor adhesion characteristics, and these results are likely related to the plating process itself. At the origin of this behavior, we might suggest thermal- induced mechanisms including formation of intermetallics and diffusion, presence of impurities at the plating-bar interface, defect propagation and stress relaxation at the interface.
{"title":"Thermal Aging Study of Tin plating on Aluminum","authors":"B. Chudnovsky, V. Pavageau, M. Rapeaux, A. Zolfaghari, P. Bardollet","doi":"10.1109/HOLM.2007.4318199","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318199","url":null,"abstract":"This paper presents a thermal study of aluminum with tin plating deposited on Al using three different types of tin plating using various cyanide and non-cyanide processes. We determined the quality of plating before and after it was exposed to the temperature of 150degC in air for up to eight weeks using multiple testing techniques, such as adhesion test, thermal shock test, SEM techniques, EDS X-ray analysis, and thickness measurements. We determined that after aging test tin plating shows aging related cracks, voids and separation appearing at the plating interfaces although in different concentration and progression rates depending on plating technique. All types of plating demonstrated deteriorated plating adhesion. Accelerated thermal aging tests at 150degC discriminate plating types. Aged samples exhibit medium to poor adhesion characteristics, and these results are likely related to the plating process itself. At the origin of this behavior, we might suggest thermal- induced mechanisms including formation of intermetallics and diffusion, presence of impurities at the plating-bar interface, defect propagation and stress relaxation at the interface.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90909252","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 : 2007-09-24DOI: 10.1109/HOLM.2007.4318194
W. Hauer, P. Zeller, Xin Zhou
In this paper test results of low voltage Molded Case Circuit Breakers (MCCB) are discussed with respect to two basic design principles: single-break design and double-break design. Experiment were carried out using a discharge bank test system at three different prospective fault current levels 10 kA, 24 kA, and 37 kA. Test results show that the two basic design principles have different influences on characteristic switching parameters such as arc voltage, arc current, I2t, VIdt, and pressure. At low current levels, the single-break design has advantages over the double-break design because the double-break design re-closes during short circuit events. The contact re-closing causes higher I2t and VIdt in comparison with those of the single-break design. While strong interaction between arc and chamber material in a small arc chamber volume as well as two arcs generated by the double-break design leads to effective current limiting with fast rise of arc voltage to a high arc voltage level, but it also causes strong material evaporation and high pressure. Test results also indicate that MCCB performance can vary significantly even though using the same design principle due to other design variations. In order to fully evaluate performances of these two design principles, power tests such as high fault current interruption, overload, and temperature rise tests required by UL or IEC standards need to be carried out.
{"title":"Benchmark Tests of Single-Break and Double-Break Design Principles","authors":"W. Hauer, P. Zeller, Xin Zhou","doi":"10.1109/HOLM.2007.4318194","DOIUrl":"https://doi.org/10.1109/HOLM.2007.4318194","url":null,"abstract":"In this paper test results of low voltage Molded Case Circuit Breakers (MCCB) are discussed with respect to two basic design principles: single-break design and double-break design. Experiment were carried out using a discharge bank test system at three different prospective fault current levels 10 kA, 24 kA, and 37 kA. Test results show that the two basic design principles have different influences on characteristic switching parameters such as arc voltage, arc current, I2t, VIdt, and pressure. At low current levels, the single-break design has advantages over the double-break design because the double-break design re-closes during short circuit events. The contact re-closing causes higher I2t and VIdt in comparison with those of the single-break design. While strong interaction between arc and chamber material in a small arc chamber volume as well as two arcs generated by the double-break design leads to effective current limiting with fast rise of arc voltage to a high arc voltage level, but it also causes strong material evaporation and high pressure. Test results also indicate that MCCB performance can vary significantly even though using the same design principle due to other design variations. In order to fully evaluate performances of these two design principles, power tests such as high fault current interruption, overload, and temperature rise tests required by UL or IEC standards need to be carried out.","PeriodicalId":11624,"journal":{"name":"Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73030630","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：