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Electrical Contacts, 2005. Proceedings of the Fifty-First IEEE Holm Conference on

Date 26-28 Sept. 2005

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Displaying Results 1 - 25 of 69
  • The influence of contact interface characteristics on vibration-induced fretting degradation

    Publication Year: 2005 , Page(s): 82 - 88
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (625 KB) |  | HTML iconHTML  

    Vibration induced fretting degradation is a widely recognized failure phenomenon; however, the basic mechanisms that control the onset and progression of such fretting behavior are not well understood and are a topic of considerable interest in the electrical connector community. One specific issue is the need for a more detailed understanding of the mechanisms controlling the fretting degradation. The present study addresses these questions and develops answers using the results from a series of experimental tests of sample connectors which are subjected to single-frequency vibration profiles at room temperature. These test specimens are a series of dual-row 16-circuit automotive connectors in which the plating finish and contact normal force are varied. The results are presented and discussed in light of earlier investigations. View full abstract»

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  • Contact contamination and arc interactions

    Publication Year: 2005 , Page(s): 1 - 9
    Cited by:  Papers (2)
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    Contact contamination is a major problem for all types of contacts but is more complex for arcing contacts as a result of arc interactions with the contact surface and contaminants. The paper describes arc interactions with mineral particulate and resultant resistances. The complexities of silicone film contamination, migration, and silicon oxide build up are described. The paper also describes the effect of difference automotive loads on silicone reactions. Special arc reactions that occur as a result of silver refractory metal oxidation potential are discussed. For silver contacts, the reasons for high and unstable resistances for DC inductive load applications are discussed. The paper is mainly a review with some added new material. View full abstract»

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  • Rating power connectors using voltage drop

    Publication Year: 2005 , Page(s): 176 - 179
    Cited by:  Papers (2)
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    Typically, measuring temperature rise at rated current has been used to rate power contacts in connector applications. In some cases this is done after accelerated aging tests. In this paper, it is proposed that voltage drop and change in voltage drop be used to evaluate the performance of power contacts. This method is intended to replace the standard use of thermocouples to monitor performance throughout an accelerated test series. Criterion is developed empirically from high current testing of tin plated power contacts. Moreover, data from accelerated aging tests followed by high current cycling tests are used to establish an empirical basis for change in voltage drop criteria. These results are analyzed using basic contact theory to relate loss of metallic contact to change in voltage (resistance) criteria. The ultimate goal is to develop a method using voltage drop as a performance indicator to quantify the current level at which power contacts reliably work. To this end, a series of tests are conducted at various current levels to establish a relation between current level and failure rate. Subsequently, the relationship of voltage drop stability and reliability are established to provide a methodology in current rating power contacts. View full abstract»

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  • Vibration-induced deterioration of tin-coated connectors studied by using a force controlled fretting bench-test

    Publication Year: 2005 , Page(s): 97 - 106
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2031 KB) |  | HTML iconHTML  

    The deterioration of tin-coated connectors caused by vibration was studied by using a new approach. In order to simulate the true contact situation during vibration, a controlled oscillating tangential force was applied on a model tin-contact, while the displacement was free to vary. This study shows that the friction and the amplitude of the tangential force acting on the contact are critical parameters for a contact subjected to vibration, since they have a significant impact on the relative slip at the contact interface. Almost any slip (>1 μm) resulted in an increased contact resistance in the performed experiments. Initial slip caused an increase of the contact resistance, and also an increase of the contact area with a subsequent increase in friction force. The slip came to stop, as the friction force became equal to the applied tangential force. Provided the slip was stopped before the contact failed as described, a stable contact resistance was achieved despite an applied oscillating tangential force. In all other, cases the slip continued and the contact inevitably failed. With a force controlled fretting bench test the critical tangential force for a specific contact can easily be determined, and the results can be used to predict the risk for fretting corrosion. View full abstract»

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  • Synthesis and characterization of Ti-Si-C compounds for electrical contact applications

    Publication Year: 2005 , Page(s): 277 - 283
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    We present a growth study of Ti-Si-C thin films on Cu and Al substrates for contact resistance studies. The films were grown by magnetron sputtering from Ti3SiC2 compound targets at temperatures from 100 °C to 300 °C. The films consist of TiCx nanocrystallites embedded in an amorphous SiC matrix. Mechanically, the Ti-Si-C films exhibit a nanoindentation hardness of 20 GPa and an elastic modulus of 290 GPa, reflecting a carbidic nature but with a remarkable ductile behavior. In electrical contact studies, the contact resistance of the Ti-Si-C films, deposited on Ni-plated Al washers at 300 °C, against Ag was comparable to that of Ag against Ag at high contact forces (6 μΩ, and 3.2 μΩ, respectively, at 800 N). At lower forces the difference is significant due to the formation of surface oxides. In a crossed cylinder setup, the contact resistance of Ti-Si-C films deposited on Ni-plated Cu cylinders is typically a factor 5 higher than that of Ag against Ag. Encouragingly, Ti-Si-C films deposited at 100 °C exhibited contact resistances less than double of that of films deposited at 300 °C. We conclude that, while significant work remains on process optimization and analysis, Ti-Si-C has high potential in general electrical contact applications. View full abstract»

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  • Time-coordinated nonarcing breaking operation of reed switches for higher current

    Publication Year: 2005 , Page(s): 139 - 143
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (488 KB) |  | HTML iconHTML  

    At the 50th IEEE Holm conference, we proposed a method for suppressing arc ignition in mechanical contact devices using a transient current switch and a capacitor. We applied the method to conventional reed switches. For the electric circuit analysis, we clarified the momentary voltage-current characteristics at the reed switch breaking operation by FEM analysis. We were able to estimate the nonarc ignition breaking condition using SPICE simulation. It was experimentally confirmed with the capacitor of 9.4μF for 24V/15A breaking operation. View full abstract»

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  • Displacement measurements at the connector contact interface employing a novel thick film sensor

    Publication Year: 2005 , Page(s): 89 - 96
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (580 KB) |  | HTML iconHTML  

    One of the key failure mechanisms for wiring and connector systems used in the automotive industry is fretting and fretting corrosion at the contact interface of connectors. For many years, procedures have been carried out under laboratory controlled conditions to investigate both thermal and vibration fretting effects using environmental chambers and fretting tests. Both optical and visual inspections have also been adopted to observe the movement at the contact interface. However, these methods can be considerably inconvenient and costly. Furthermore, their suitability for field applications is limited. In order to study the fretting degradation at the actual interface for in-situ measurement effectively, a novel position sensor is designed to monitor the relative displacement. Thick film techniques are employed to fabricate miniaturised and cost effective resistive devices. The sensor is assembled into a connector sample by taking the place of the male component. When the interface experiences movement, the relative displacement of the contact point would cause a corresponding linear change of resistance measured across the male and female connection. The sensors are validated by a series of experiments and subsequently used in a field test to establish the relationships between the fretting effects with temperature, humidity and differential pressure. It is found that variation in differential pressure dominates the behaviour of movement at the contact interface of the well-sealed connector sample while temperature and humidity have negligible influences on the measured relative displacement. View full abstract»

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  • Substitution of silver/cadmium oxide in high voltage disconnectors

    Publication Year: 2005 , Page(s): 42 - 47
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1702 KB) |  | HTML iconHTML  

    In high voltage substations with multiple busbar configuration, a load transfer without load interruption from one busbar to another is a common operation. For this task, disconnectors with an interruption capability up to 0.5 MVA are used which have to manage switching arcs at the break as well as at the make operation. Pantograph disconnectors are well known as reliable and space-saving solutions. There are two possibilities for the contact systems. The combination of current-carrying contacts and switching contacts has a considerable advantage in comparison to the use of additional low erosion pretravel contacts. Up to now, silver cadmium oxide (Ag/CdO) is used as an arc resistant contact material for pantograph disconnectors without pretravel contacts. Due to an increasing environmental awareness the Ag/CdO should be replaced by a more environmentally friendly material. It is shown that an optimized silver tin oxide (Ag/SnO2) material with additives fulfills the requirements. In regard to the switching behavior, Ag/SnO2 is superior to Ag/CdO and even in comparison to pure silver contacts it shows an equal current carrying behavior. On the basis of the results Ag/CdO can be replaced in pantograph disconnectors. View full abstract»

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  • Electrochemical migration of land grid array sockets under highly accelerated stress conditions

    Publication Year: 2005 , Page(s): 238 - 244
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1066 KB) |  | HTML iconHTML  

    Land grid array sockets are used as separable interconnects between printed circuit boards and high I/O integrated circuit components. Metal-in-elastomer land grid array sockets consist of an array of elastomer contacts, a polyimide insulator and a thermoplastic frame. Silver particles are embedded in the silicone elastomer as contact medium to provide electrical paths between a printed circuit board and a component. In order to assess the reliability of this type of socket, biased, highly accelerated stress testing (HAST) was conducted. The surface insulation resistance (resistance between two adjacent contacts) was monitored, and was found to decrease significantly. Silver electrochemical migration (ECM) was identified as the cause. Both dendrites and film were observed on the polyimide insulator surface as a result of ECM. The dendrite grows from cathode contact to anode on the polyimide insulator surface. The ECM products were analyzed using both energy dispersive spectroscopy and X-ray photoelectron spectroscopy. Silver and silver oxides were detected as ECM products on the polyimide surface after HAST exposure. The potential chemical mechanism of silver electrochemical migration was described based upon the analysis of the ECM products. View full abstract»

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  • Inspection of the contaminants at failed connector contacts

    Publication Year: 2005 , Page(s): 115 - 120
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1263 KB) |  | HTML iconHTML  

    Inspection on 95 failed connector contacts of 23 mobile phones shows that the contaminants at the contact areas are formed by various sizes of particles. They are adhered together. It seems that smaller ones accumulate the larger ones. The composition of contaminants is very complex, which include dust particles containing mainly silicates (quartz, mica, feldspar) and calcium compounds (gypsum, calcite and lime), wear debris of surface materials, corrosion products (sulfates, chlorides and oxides of copper and nickel) and high concentration of organics. Organic materials seem to act as adhesives at different temperatures. Contaminants causing failure usually located at or near the wear tracks. The most important function of micromotion is to move the separated contaminants and accumulate them together at the contact; they also produce wear debris, and destroy the surface metal layer as well. High contact resistance happened in several small regions at the contaminant that provide high enough thickness. Failure could be happened within very short time period (3-4 months) depends on the high resistance region is formed. Conventional ways of corrosion gas test, sand or artificial dust test, shock and vibration test can hardly simulate the failure of contact occurred in China. View full abstract»

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  • An arc study at high DC current levels in automotive applications

    Publication Year: 2005 , Page(s): 329 - 334
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    In order to fulfil the increasing electric power needs in automobiles and to satisfy new environmental requirements and security, the currently used 14 VDC electrical power systems, must either supply higher currents (up to 100 A) or be changed to 42 V. Considering the difficulties of operating with this new 42 V system, we have focused our interests on higher currents by extending our previous 14 VDC study. The arc parameters such as break arc duration and extinction gap for different materials and circuit loads are investigated. We have established that these main arc parameters are greatly influenced by load (inductance) and contact materials. The behavior of the material is investigated according to the composition, oxide content and doping agent in silver. As found for low currents, the material transfer direction from the anode to the cathode is maintained at high current and neither opposite transfer direction or bilateral erosion was observed. View full abstract»

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  • Effect of short circuit current duration on the welding of closed contacts in vacuum

    Publication Year: 2005 , Page(s): 69 - 74
    Cited by:  Papers (4)
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    High ac currents were passed through closed Cu-Cr (25 wt. %) contacts located in a vacuum ambient (pressure 10-4-10-3 Pa). The duration of the short circuit currents ranged from 1 second to 4 seconds. The contact welding was measured for a range of closed contact forces and current durations. The weld fracture strength was measured using a slowly rising opening force of 50 N/s. It was found that the contacts required a larger contact force to prevent welding if the current duration of 4 seconds was applied, than if a current of 1 second, 2 seconds and 3 seconds was applied. The data showed that there was a considerable scatter in the data for all conditions examined. It also showed that a weak weld could well follow a strong weld. A consideration of the transition to the steady state model of closed contact welding can explain the observed data. View full abstract»

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  • Multi-scale study of the electrical properties of organic layers grafted on gold surfaces

    Publication Year: 2005 , Page(s): 245 - 254
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1630 KB) |  | HTML iconHTML  

    Many studies have been performed on the corrosion and fretting degradation mechanisms of gold plated contacts for low level applications. Reliability requirements constantly increase and finding new solutions able to postpone degradations is still a challenge. A large study has led to the elaboration of a fluorinated organic film grafted to the surface and allowing outstanding protection of the gold surfaces. These organic films involved new thiol functionalized perfluoro polyethers, deposited as mixed layers. Back-panel connector systems coated with various fluorinated organic films were submitted to a four gases corrosion test (Bellcore uncontrolled environment test). High values of the contact resistance Rc were found for the contacts coated with some of the films. The present study is aimed at understanding the electrical properties of these films. The electrical behavior of model contacts (dimple on flat) was investigated in static and in dynamic modes. Fretting experiments showed the combined influence of friction and of the surface roughness. Finally the electrical properties were investigated at a more microscopic scale. An experiment performed with a modified AFM microscope with a conducting probe (CP-AFM) showed the particular behavior of functionalized PFPE lubricant on gold. Results are discussed in order to have an insight into the conduction mechanisms involved. View full abstract»

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  • Multi-spot model showing the effects of nano-spot sizes

    Publication Year: 2005 , Page(s): 291 - 297
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (320 KB) |  | HTML iconHTML  

    A multi-spot stochastic model is developed to calculate the resistance of degraded contacts. Variables such as number and size of contact spots, and thickness and resistivity of oxide films are varied randomly to simulate the impact on contact resistance. In addition, the effects of small contact spots are estimated using the Sharvin and Wexler equations for cases where the Knudsen ratio is small (where the size of a contact spot approaches or falls below the collision mean free path of electrons). The results are used to show the statistical variations in contact resistance due to random variations in film characteristics. Test data are provided as a comparison to the model predictions and are used to validate the model results. View full abstract»

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  • Lubrication of electrical contacts

    Publication Year: 2005 , Page(s): 107 - 114
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (233 KB) |  | HTML iconHTML  

    The paper presents a review of research data published during last 40-year period in the field of electrical contact lubrication. The paper examines the role of lubrication in corrosion protection as a barrier between contact surfaces and atmospheric pollutants. For effective long-term corrosion protection, it is important to properly choose and thoroughly qualify a lubrication product for a specific contact material and a specific combination of environmental variables. Another use of lubricants is to protect contacts from mechanical wear and/or friction, and from degradation due to fretting. Conversely, use of inappropriate lubricants may induce a significant risk by producing degradation, collecting participate matter, and developing a high electrical resistance of the contact surfaces. It is very important to carefully choose the lubricants to maintain a stable contact resistance and preserve the physical integrity of the contact surface. This paper also analyzes the effect of chemical composition and consistency (fluids, greases, solid lubricants) on the durability of lubricants in regards to various types of contact material, design and load. View full abstract»

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  • Asynchronous modular contactor for intelligent motor control applications

    Publication Year: 2005 , Page(s): 55 - 62
    Cited by:  Papers (2)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (865 KB) |  | HTML iconHTML  

    R&D activities have been carried out for decades by many researchers in order to improve electromechanical contactor performance employing electronic control. This includes electronic controlled contactor opening to minimize contact erosion, and closing to reduce contact bounce. But the improvement is limited with significant increase of cost and size due to the inherent design structure of contactors: simultaneously switching of all three poles. Meanwhile, solid-state motor starters have shown great benefit with point-on-wave (POW) switch-on to minimize transient current and torque stress of induction machines during motor starting process. However, cost and size is a premium. A novel technology that employs asynchronous modular concept and POW switching has been developed. This improves motor starting and contactor switching performances in respect to switching transients and contact erosion while utilizing small size and low cost electromechanical contactors. These contactors are assembled into a flexible modular contactor assembly that allows each pole to be switched independently with precise POW switching control. This paper focuses on motor starting applications to achieve significant reduction of motor starting transients and contactor switching capability improvement. Asynchronous modular contactor prototypes with newly developed 24VDC controlled contactors have been developed. The evaluation tests of the prototype proved significant transient current and torque stress reduction during motor starting. View full abstract»

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  • Micro motion at the failed contact interfaces

    Publication Year: 2005 , Page(s): 180 - 185
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1127 KB) |  | HTML iconHTML  

    On inspection of failed connector's contacts, various wear tracks of micro motion are found. The tracks appear as straight line, curve and twisting. The effect of micro motion not only produces wear debris of contact metals and their oxidation products, but also grabbles and accumulates contaminants which cause high and fluctuated contact resistance. Analysis on the cause of micro motion that related to external vibration and shocks are carried out. Supporting experimental results are also discussed. View full abstract»

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  • A model for life time evaluation of closed electrical contacts

    Publication Year: 2005 , Page(s): 217 - 223
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (564 KB) |  | HTML iconHTML  

    A model for evaluating the lifetime of closed electrical contacts was described. The model is based on the diffusion of oxidizing agent into the contact zone. The results showed that there is good agreement between the experimental data as reported by different authors in the literature and the derived expressions for the limiting value of contact lifetime. View full abstract»

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  • The evolution of arc fault circuit interrupters

    Publication Year: 2005 , Page(s): 156 - 161
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (133 KB) |  | HTML iconHTML  

    Traditionally, circuit breakers and fuses have provided overcurrent and short circuit protection in electrical distribution applications. Despite this protection, approximately 70,000 residential fires with more than 500 deaths and Å in property damage occur each year in the U.S. that are attributed to electrical initiation. When investigated it was found that in some cases the circuit breaker had not tripped. Arc fault circuit interrupters can recognize the unique signatures of arcing faults and initiate a trip condition to isolate and de-energize the arcing fault. This paper identifies the conditions that can lead to fire hazards. These include arcs to ground, wiring failure modes, earth leakage conditions and high resistance faults such as glowing contacts, and in-line low current arcs (sometimes referred to as series arcs). View full abstract»

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  • Influence of surface roughness on contact voltage drop of sliding contacts

    Publication Year: 2005 , Page(s): 324 - 328
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (511 KB) |  | HTML iconHTML  

    Usually, sliding contact action is used to supply current to a rotating or a moving object. In the present experiment, we examined the relation between surface roughness condition and contact voltage drop for sliding contacts. We used carbon brush and copper slip ring for sliding materials. It is confirmed that the contact voltage drop tends to decrease for large roughness surface condition of sliding materials. However, in case of the brush surface roughness is same to slip ring surface roughness, the contact voltage drop is increased. The present work has demonstrated that the relation between surface roughness condition and contact voltage drop for electrical sliding contact action. View full abstract»

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  • On the spontaneous growth of soft metallic whiskers

    Publication Year: 2005 , Page(s): 121 - 126
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    The room temperature spontaneous growth of low melting point metal whiskers, such as Sn, poses a serious reliability problem in the semiconducting industry; a problem that has become acute with the introduction of Pb-free solder technology. Recently it was shown that the driving force is most probably a reaction between oxygen and the sprouting metal (Barsoum, 2004). The resulting volume expansion creates a compressive stress that pushes the whiskers up. The model proposed explains observations on In and Sn whiskers as well as many past observations. Herein further evidence is presented for, and discussion of, the proposed model. Stresses, calculated using finite element modeling, are reasonable and in line with measured values. Based on this work, a potential solution to the whisker problem is in principle simple: either slow or prevent the diffusion of oxygen into the soft metal or, more practically and effectively, work with larger grained solder, which should reduce the magnitude of the compressive stresses. View full abstract»

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  • Conditions for series arcing phenomena in PVC wiring

    Publication Year: 2005 , Page(s): 167 - 175
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (929 KB) |  | HTML iconHTML  

    Under certain circumstances, unintentional series arcing, caused from damaged line cords and loose connections, can pose a serious fire and safety hazard. This work, focusing on residential 115 Vac applications, shows how continuous bursts of ignited gases can be created from overheated PVC insulation created from glowing contacts with subsequent series arcing, or surface breakdown with subsequent series arcing. Also, surprisingly, these potentially hazardous fire conditions were created with currents as low as 0.9 Arms, at 115 Vac (100 W lamp load). Little research is available about the interaction of glowing contacts, formed from loose or broken copper conductors in wiring (outlets, switches, line conductors, etc.), with electrical insulation. This work shows how glowing contacts and surface arcing can decompose PVC insulation, form ignitable gases, and that it is possible for the subsequent series arc to ignite, and burn insulation. Two conditions are identified that can create an overheated connection - a glowing contact and/or breakdown over a charred insulation surface. Mechanisms are discussed along with data for glowing contact voltage drop, photographs of glowing connections, and a gas chromatograph analysis of the evolved gases emitted from overheated PVC wiring. Selected high-speed video frames (1000 fps) taken from videos of the series arc and bursts of ignitable gasses along with synchronized current and voltage waveforms over a current range of 0.9 Arms to 5 Arms are presented. These findings are useful for advancing the state-of-the-art in fire protection by providing a better understanding of how electrical fires can initiate. View full abstract»

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  • Micro phenomena in low contact-force probing on aluminum

    Publication Year: 2005 , Page(s): 259 - 264
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (901 KB) |  | HTML iconHTML  

    Electric contact phenomena in probing of aluminum electrode under low contact force have been investigated. Metallic materials of wide variety were tested to find one suitable for low contact-force probing on aluminum using fritting. In order to investigate the low-force contact phenomena, a new measurement apparatus was developed to enable the control of contact force less than 1 mN, and direct observation of the probe tip during the repeated contact measurement. Silver, gold and platinum were found to be suitable materials for probes for fritting contact, and good electric contacts more than 1,000 counts were obtained. The tip of the probe was observed by an optical microscope and adhesion of the aluminum electrode was investigated. View full abstract»

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  • Long-term high resolution wear studies of high current density electrical brushes

    Publication Year: 2005 , Page(s): 304 - 311
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (951 KB) |  | HTML iconHTML  

    With renewed interest in sliding electrical contacts for application in doubly-fed asynchronous induction wind turbine generators, focus on optimizing the wear life of high current density electrical brushes has re-emerged. This is due to the service and maintenance costs associated with some wind turbine sites, especially offshore. An automated test apparatus has been built and tests conducted to study the long-term wear behavior of silver-graphite brushes running on tin-bronze slip rings with high time- and spatial resolution. The results of the tests have shown that the tribo-film deposited on the slip ring adapts rapidly to changing operating conditions such as current load. The tests have also indicated that the long-term brush wear behavior is surprisingly dynamic and that the wear process may be subject to tribo-film instabilities which account for short periods of rapid wear separated by longer periods of mild wear. View full abstract»

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  • Finite element analysis of magnetic structures for micro-electro-mechanical relays

    Publication Year: 2005 , Page(s): 265 - 269
    Cited by:  Papers (1)  |  Patents (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (528 KB) |  | HTML iconHTML  

    Micro-electro-mechanical system technology offers great promise in addressing the need for smaller electromechanical relays, and may bridge the performance and economic gaps between conventional electromechanical technology and solid state devices. It is necessary for electromagnetic field analysis during design process of micro-electro-mechanical relay. Planar coil and magnetic plate structures were modeled by using finite element method in this paper. Furthermore the open domain magnetic field views of micro-electro-mechanical relay with different structures were compared. And the electromagnetic attraction force of movable contacts in MEMS relay was analyzed, thus can not only simplify the fabrication procedure, but also develop the working performance of products. The results of the analysis can be useful for designers to develop optimal magnetic structure of micro-electro-mechanical relays. View full abstract»

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