ASTM_B_854_-_98_2016.pdf

Designation:B85498(Reapproved 2016)Standard Guide forMeasuring Electrical Contact Intermittences1This standard is issued under the fixed designation B854;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 The techniques described in this guide apply to electri-cal circuits that include one or more electrical contacts indevices such as slip rings,separable connectors,electrome-chanical relays or closed switch contacts.The user shoulddetermine applicability for other devices.1.2 The range of techniques described apply to circuitdiscontinuities(intermittences)of durations ranging from ap-proximately 10 nanoseconds to several seconds and of suffi-cient magnitude to cause alteration of the circuit function.Extension of the guide to shorter duration events may bepossible with suitable instrumentation.Events of longer dura-tion may be monitored by techniques for dc measurementssuch as those described in Test Methods B539 or by adaptationof methods described in this guide.1.3 The techniques described in this guide apply to electri-cal circuits carrying currents typical of signal circuits.Suchcurrents are generally less than 100 ma.Extension of thesetechniques to circuits carrying larger currents may be possible,but the user should evaluate applicability first.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to become familiarwith all hazards including those identified in the appropriateSafety Data Sheet(SDS)for this product/material as providedby the manufacturer,to establish appropriate safety and healthpractices,and determine the applicability of regulatory limi-tations prior to use.2.Referenced Documents2.1 ASTM Standards:2B539 Test Methods for Measuring Resistance of ElectricalConnections(Static Contacts)B542 Terminology Relating to Electrical Contacts and TheirUseB615 Practice for Measuring Electrical Contact Noise inSliding Electrical ContactsB878 Test Method for Nanosecond Event Detection forElectrical Contacts and Connectors2.2 Other Documents:IEC Publication 512 Test 2e Contact Disturbance3EIA-364-46 Continuity Test Procedure for Electrical Con-nectors43.Terminology3.1 Terms relevant to this guide are defined in TerminologyB542 except as noted in the following section.3.2 Definitions of Terms Specific to This Standard:3.2.1intermittence,na transient increase in the voltagedrop across a pair of electrical contacts.4.Significance and Use4.1 This guide suggests techniques to evaluate intermit-tences in a contact pair while it is subjected to simulated oractual environmental stress.Such measurements are a valuabletool in predicting circuit performance under these stressconditions and in diagnosing observed problems in circuitfunction under such conditions.4.2 This document is intended to provide some generalguidance on the best available practices for detecting,quantifying,characterizing and reporting short duration inter-mittences in circuits containing electrical contacts.Certainenvironmental stresses such as mechanical shock,vibration ortemperature change may cause intermittences.These measure-ment procedures include methods applicable to contacts oper-ating under various conditions in testing or in service.4.3 Practice B615 defines methods for measuring electricalcontact noise in sliding electrical contacts.In contrast Guide1This guide is under the jurisdiction of ASTM Committee B02 on NonferrousMetals and Alloys and is the direct responsibility of Subcommittee B02.11 onElectrical Contact Test Methods.Current edition approved May 1,2016.Published May 2016.Originallyapproved in 1998.Last previous edition approved in 2010 as B854 98(2010)1.DOI:10.1520/B0854-98R16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.4Available from Electronic Industries Association,2001 Pennsylvania Ave NW,Washington D.C.20006.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 B854 provides guidance to the various methods for measuringsimilar phenomena in static contacts.5.Apparatus5.1 General CommentsThe apparatus required varies de-pending upon the technique selected and the parameters(suchas duration and magnitude)of the intermittence that the userwants to detect.In general,the cabling must be capable ofcarrying signals of the speed