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This guide defines the criteria for composition, properties, and other requirements for miniature brushes of composite materials containing a matrix of one or more conducting metallic elements or alloys and one or more lubricating lamellar solids intended for sliding electric contacts. Each constituent of the material should be listed individually by weight percent including tolerances using any analytical technique while the apparent density for the material should be defined using the measurement and weight method. The resistivity; Rockwell superficial hardness, transverse strength, and shear strength; and microstructural properties such as cracks and defects should also be defined and should conform to the required electrical, mechanical, and structural properties of the brush materials.1.1 This guide defines the criteria for composition, properties, and other requirements for brushes containing a matrix of one or more conducting metallic elements or alloys and one or more lubricating lamellar solids.1.2 The resulting specification is intended for use where the size (for example, 5 mm by 3 mm by 2 mm), shape, or other factors preclude the determination of properties on specimens of the bulk material from which individual brushes are made.1.3 The requirements recommended herein have been found to be desirable for most brush material composites. Care must be taken in preparing a specification for a pre-existing material that imposition of one or more provisions herein does not alter the material or its performance.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 Resistance or voltage values alone do not provide sufficient detail for an engineering evaluation of contact noise. This practice lists the test conditions that should be reported with noise measurements and indicates some conditions (open circuit voltages, currents, etc.) that have been used for quality control and research studies. The use of these practices should provide sufficient detail for an engineering interpretation of the noise data and allow the tests to be repeated by another laboratory.1.1 This practice describes the practices and factors considered to be most important in the measurement of electrical contact noise of sliding contacts.1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Preservation of a conducting surface on electrical contact is vital to the continued functioning of such contacts. Contamination of the surface with insulating layers formed by corrosion processes is one potential hazard. Laboratory testing of contacts in MFG tests is used to assess the effectiveness of design features and materials.4.2 MFG tests are used in development studies of processes and materials for contacts. For example, coupon specimens may be exposed to MFG tests to evaluate new contact materials, layers of new coating materials on a supporting substrate, reduced coating thicknesses, or protective surface treatments.4.3 MFG tests are also employed to test the durability of a finished product with respect to atmospheric corrosion. For example, finished connectors may be exposed to a MFG test and their performances compared against each other or against a set of fixed requirements. Relays or switch contacts may be exposed in the operated and non-operated conditions to compare performance.4.4 MFG tests are useful for determining the effectiveness of connector housings and shrouds as barriers to ingress of atmospheric corrodants to the contact surfaces. These tests can also be used to assess the screening of the metal-to-metal contact areas of mated connectors.4.5 MFG tests are employed as qualification tests to determine connector failure rates in application environments for which correlation between test and application has previously been established.4.6 This guide provides test conditions which are to be applied in conjunction with Practice B827 which defines the required test operation and certification procedures, tolerances, and reporting requirements. Where the test specifier requires certifications or tolerances different than those provided in Practice B827, the required certifications or tolerances shall be part of the test specification. Differences from the specifications in Practice B827 shall be reported in the test report provided by the test operator to the test specifier. Specification of one of the test conditions defined in this document in the form of a statement such as, “Parts shall be tested in accordance with ASTM B845 Method Z,” implicitly requires test condition, Z, applied according to Practice B827.1.1 The techniques described in this guide pertain to mixed flowing gas (MFG) tests containing species that are applied to evaluate devices containing electrical contacts such as slip rings, separable connectors, electromechanical relays or switch contacts. These techniques may be relevant to other devices, but it is the responsibility of the user to determine suitability prior to testing.1.2 The MFG tests described in this guide are designed to accelerate corrosive degradation processes. These accelerations are designed such that the degradation occurs in a much shorter time period than that expected for such processes in the intended application environment of the device being tested. Application environments can vary continuously from benign to aggressively corrosive. Connectors and contacts within closed electronic cabinets may be affected by an environment of different severity than the environment on the outside of such cabinets. In general, indoor environments are different than outdoor environments. The MFG tests described herein, being discrete embodiments of specific corrosive conditions, cannot be representative of all possible application environments. It is the responsibility of the test specifier to assure the pertinence of a given test condition to the specifier's application condition.1.3 The MFG tests described herein are not designed to duplicate the actual intended application environment of the device under test. An extended bibliography that provides information which is useful to test specifiers to assist them in selecting appropriate test methods is included in this guide. The bibliography covers the scope from application condition characterization, single and multiple gas effects, and material and product effects to key application and test variables as well as discussions of atmospheric corrosion processes.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The tests in this test method are designed to assess the resistance stability of electrical contacts or connections.4.2 The described procedures are for the detection of events that result from short duration, high-resistance fluctuations, or of voltage variations that may result in improper triggering of high speed digital circuits.4.3 In those procedures, the test currents are 100 mA (±20 mA) when the test sample has a resistance between 0 and 10 Ω. Since the minimum resistance change required to produce an event (defined in 3.2.1) is specified as 10 Ω (see 1.3), the voltage increase required to produce this event must be at least 1.0 V.4.4 The detection of nanosecond-duration events is considered necessary when an application is susceptible to noise. However, these procedures are not capable of determining the actual duration of the event detected.4.5 The integrity of nanosecond-duration signals can only be maintained with transmission lines; therefore, contacts in series are connected to a detector channel through coaxial cable. The detector will indicate when the resistance monitored exceeds the minimum event resistance for more than the specified duration.4.6 The test condition designation corresponding to a specific minimum event duration of 1, 10, or 50 ns is listed in Table 1. These shall be specified in the referencing document.1.1 This test method describes equipment and techniques for detecting contact resistance transients yielding resistances greater than a specified value and lasting for at least a specified minimum duration.1.2 The minimum durations specified in this standard are 1, 10, and 50 nanoseconds (ns).1.3 The minimum sample resistance required for an event detection in this standard is 10 Ω.1.4 An ASTM guide for measuring electrical contact transients of various durations is available as Guide B854.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Material Safety Data Sheet (MSDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This test method provides a way to detect contamination on printed wiring board fingers that affects the electrical performance of such fingers. Such contamination may arise during PWB manufacture, circuit assembly, or service life and may include solder mask, solder flux, hardened lubricants, dust, or other materials. This test method provides a nondestructive method of inspecting such fingers at any point in the life of the product including after original manufacture, after assembly of circuit components to the PWB, and after time in service such as when returned for repair. Because this test method uses two probes to finger contacts in series, it provides a sensitive test for contaminants that may increase electrical resistance when the fingers are plugged into an edgecard connector that typically makes contact to the finger through only one contact to finger interface.5.2 Practice B667 describes a more general procedure for measuring contact resistance of any solid material in practically any geometrical form. The method in Practice B667 should be used for general studies and fundamental studies of electrical contact materials.1.1 This test method defines a resistance probing test for detecting the presence of foreign matter on Printed Wiring Board (PWB) contacts or fingers that adversely affects electrical performance. This test method is defined specifically for such fingers coated with gold. Application of this test method to other types of electrical contacts or to fingers coated with other materials may be possible and desirable but may require some changes in fixturing, procedures, or failure criteria.1.2 Practice B667 describes another contact resistance probe method that has more general application to electrical contacts of various materials and shapes. Practice B667 should be used for more fundamental studies. This test method provides a fast inspection method for printed wiring board fingers.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar will all hazards including those identified in the appropriate Material Safety Data Sheet (MSDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This specification establishes the requirements for copper alloy strips for use in the manufacture of electrical connectors or spring contacts produced from one of the following Copper Alloy UNS Nos.: C14530, C15100, C15500, C17000, C17200, C17410, C17450, C17460, C17500, C17510, C19010, C19025, C19210, C19400, C19500, C19700, C23000, C26000, C40810, C40850, C40860, C42200, C42500, C42520, C42600, C50580, C50780, C51000, C51080, C51100, C51180, C51980, C52100, C52180, C52480, C63800, C65400, C68800, C70250, C70260, C70265, C75200, and C76200. The material for manufacture shall be a cast bar, slab, cake, billet, or other form of such composition as to be suitable for processing by either hot- or cold-working to produce the products prescribed in this specification. Products shall be finished by hot working, cold working, annealing, or heat treatment as may be necessary to meet mechanical property requirements, which include tensile strength, yield strength, and elongation. Tempers shall be available in the annealed, rolled, or mill hardened conditions. Products shall also adhere to tolerances as to dimension such as thickness, width, length, straightness, and mass.1.1 This specification establishes the requirements for copper alloy strip for use in the manufacture of electrical connectors or spring contacts produced from one of the following Copper Alloy UNS Nos.:2 C14530, C15100, C15500, C17000, C17200, C17410, C17450, C17460, C17500, C17510, C19002, C19010, C19015, C19025, C19210, C19400, C19500, C19700, C23000, C26000, C40810, C40850, C40860, C42200, C42500, C42520, C42600, C50580, C50780, C51000, C51080, C51100, C51180, C51980, C52100, C52180, C52480, C63800, C64725, C65400, C68800, C70250, C70260, C70265, C70310, C70350, C75200, and C76200.1.2 The requirements for the other copper alloys such as copper-nickel-tin spinodal, UNS C72650, C72700, and C72900, shall be as prescribed in the current edition of Specification B740.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1 Scope This part of ISO/IEC 10373 defines test methods for characteristics of integrated circuit(s) cards with contacts and related interface devices according to the definition given in ISO/IEC 7816. Each test method is cross-referenced to one or more

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5.1 This test method is part of an overall suite of related test methods that provide repeatable measures of robotic system maneuvering and remote operator proficiency. The align ground contacts with parallel rails test challenges robotic system locomotion, operator control, effective camera positioning, chassis shape variability (if available), and remote situational awareness by the operator. As such, the align ground contacts with parallel rails test can be used to represent situations where hazards must be avoided by the robot (for example, debris, puddles) surrounding a path in the environment, highlighting situational awareness demands on the operator while controlling the robot.5.2 The scale of the apparatus can vary to provide different constraints representative of typical intended deployment environments. For example, the three configurations can be representative of repeatable complexity for unobstructed environments (open configuration), relatively open parking lots with spaces between cars (rectangular confinement configuration), or within bus, train, or plane aisles, or dwellings with hallways and doorways (square confinement configuration).5.3 The test apparatuses are low cost and easy to fabricate so they can be widely replicated. The procedure is also simple to conduct. This eases comparisons across various testing locations and dates to determine best-in-class systems and operators.5.4 Evaluation—This test method can be used in a controlled environment to measure baseline capabilities. The parallel rails apparatus can also be embedded into operational training scenarios to measure degradation due to uncontrolled variables in lighting, weather, radio communications, GPS accuracy, etc.5.5 Procurement—This test method can be used to identify inherent capability trade-offs in systems, make informed purchasing decisions, and verify performance during acceptance testing. This aligns requirement specifications and user expectations with existing capability limits.5.6 Training—This test method can be used to focus operator training as a repeatable practice task or as an embedded task within training scenarios. The resulting measures of remote operator proficiency enable tracking of perishable skills over time, along with comparisons of performance across squads, regions, or national averages.5.7 Innovation—This test method can be used to inspire technical innovation, demonstrate break-through capabilities, and measure the reliability of systems performing specific tasks within an overall mission sequence. Combining or sequencing multiple test methods can guide manufacturers toward implementing the combinations of capabilities necessary to perform essential mission tasks.1.1 This test method is intended for remotely operated ground robots operating in complex, unstructured, and often hazardous environments. It specifies the apparatuses, procedures, and performance metrics necessary to measure the capability of a robot to align its ground contacts while maneuvering across parallel rails. This test method is one of several related maneuvering tests that can be used to evaluate overall system capabilities.1.2 The robotic system includes a remote operator in control of most functionality, so an onboard camera and remote operator display are typically required. This test method can be used to evaluate assistive or autonomous behaviors intended to improve the effectiveness or efficiency of remotely operated systems.1.3 Different user communities can set their own thresholds of acceptable performance within this test method for various mission requirements.1.4 Performing Location—This test method may be performed anywhere the specified apparatuses and environmental conditions can be implemented.1.5 Units—The International System of Units (a.k.a. SI Units) and U.S. Customary Units (a.k.a. Imperial Units) are used throughout this document. They are not mathematical conversions. Rather, they are approximate equivalents in each system of units to enable use of readily available materials in different countries. The differences between the stated dimensions in each system of units are insignificant for the purposes of comparing test method results, so each system of units is separately considered standard within this test method.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This guide covers the factors to be controlled, precautions and documentation necessary to measure and report the voltage drop across closed current-carrying contacts. The voltage drop is an indication of the efficiency of the contact interfaces in carrying a specified current. This efficiency can be adversely effected by any insulating areas within the contact interface. Circuits which involve substantial current and low independence can be influenced by this contact property.1.1 This guide describes recommended procedures to accurately measure voltage drop across current carrying contacts and the parameters to be documented in order to effectively record the results. Such contacts normally carry current greater than 1 amp. The applicability of these procedures to contacts carrying smaller currents should be evaluated prior to application to such devices. Contacts carrying small current may also be evaluated using Test Method B539 to measure contact resistance. 1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Material Safety Data Sheet (MSDS) for this product/material as provided by the manufacturer, to establish appropriate safety and health practices, and determine the applicability of regulatory limitations prior to use. For specific precautionary statements, see Section 6.

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5.1 As stated in Terminology B542, contact resistance is comprised of a constriction resistance and a film resistance. When present, the latter of these is usually much greater in value and dominates the contact resistance. For a given contact spot, when the film resistance is zero or negligible the contact resistance for that spot is nearly the same as the constriction resistance and therefore, as a practical matter, has a minimum value which represents a clean metal-to-metal contact spot. As real contact surfaces exhibit varying degrees of roughness, real contacts are necessarily composed of many contact spots which are electrically parallel. In practical cases the clean metal-to-metal contact spots will carry most of the current and the total contact resistance is primarily dependent on the size and number of metallic contact spots present (see Note 1). In addition, acceptably low values of contact resistance are often obtained with true areas of contact being significantly less than the apparent contact area. This is the result of having a large number of small contact spots spread out over a relatively large apparent contact area.NOTE 1: The term metallic contact as used here is intended to include the so called quasi-metallic contact spots as well. The latter case was discussed in Electric Contacts by Holm. 35.2 The practical evaluation and comparison of electrical connections depend in large part on their contact resistance characteristics. On the one hand, the absolute value of contact resistance is greatly dependent on the size and distribution of the metallic conducting spots within the apparent area of load-bearing contact. On the other hand, a comparison of the initial resistance to the resistance after aging indicates how stable the system is in maintaining the initial contact area. Both of these characteristics should be considered when evaluating contact systems. The criteria employed in evaluating contact resistance and stability are not a part of these test methods as they depend on specific applications and therefore, will not be quantitatively stated. However, an estimate of contact resistance3 resulting from good metallic contact can be made for a given physical situation and used as a comparison to actual measurements to determine how effective the system is in establishing stable metallic contact. Resistances measured by these methods before, during and after simulated life tests are used as a means of determining the stability of contacts within a device.1.1 These test methods cover equipment and techniques for measuring the resistance of static electrical connections such as wire terminations or splices, friction connectors, soldered joints, and wrapped-wire connections.1.2 Measurements under two distinct levels of electrical loading are described. These levels are: (1) dry circuit, (2) and rated current. One or both of these levels of loading may be required in specific cases.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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