ASTM B878-97(2009)
(Test Method)Standard Test Method for Nanosecond Event Detection for Electrical Contacts and Connectors
Standard Test Method for Nanosecond Event Detection for Electrical Contacts and Connectors
SIGNIFICANCE AND USE
The tests in this test method are designed to assess the resistance stability of electrical contacts or connections.
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.
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.
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.
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.
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.
TABLE 1 Test Condition Designations for Specific Minimum Event Durations Test ConditionEvent Duration, min A 1 nanosecond B10 nanoseconds C50 nanoseconds
SCOPE
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 B 854.
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 and health practices, and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Buy Standard
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: B878 − 97(Reapproved 2009)
Standard Test Method for
Nanosecond Event Detection for Electrical Contacts and
Connectors
This standard is issued under the fixed designation B878; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2.2 Other Standards:
IEC801-2ed 2:91
1.1 This test method describes equipment and techniques
EN50 082-1:94
for detecting contact resistance transients yielding resistances
greaterthanaspecifiedvalueandlastingforatleastaspecified
3. Terminology
minimum duration.
3.1 Definitions—Many terms used in this standard are de-
1.2 The minimum durations specified in this standard are 1,
fined in Terminology B542.
10, and 50 nanoseconds (ns).
3.2 Definitions of Terms Specific to This Standard:
1.3 The minimum sample resistance required for an event
3.2.1 event, n—a condition in which the sample resistance
detection in this standard is 10Ω.
increases by more than 10 Ω for more than a specified time
duration.
1.4 An ASTM guide for measuring electrical contact tran-
sients of various durations is available as Guide B854.
4. Significance and Use
1.5 The values stated in SI units are to be regarded as
4.1 The tests in this test method are designed to assess the
standard. No other units of measurement are included in this
resistance stability of electrical contacts or connections.
standard.
4.2 Thedescribedproceduresareforthedetectionofevents
1.6 This standard does not purport to address all of the
that result from short duration, high-resistance fluctuations, or
safety concerns, if any, associated with its use. It is the
of voltage variations that may result in improper triggering of
responsibility of the user of this standard to become familiar
high speed digital circuits.
with all hazards including those identified in the appropriate
4.3 In those procedures, the test currents are 100 mA(620
Material Safety Data Sheet (MSDS) for this product/material
mA)whenthetestsamplehasaresistancebetween0and10Ω.
as provided by the manufacturer, to establish appropriate
Since the minimum resistance change required to produce an
safety and health practices, and determine the applicability of
event (defined in 3.2.1) is specified as 10 Ω (see 1.3), the
regulatory limitations prior to use.
voltageincreaserequiredtoproducethiseventmustbeatleast
1.0 V.
2. Referenced Documents
4.4 The detection of nanosecond-duration events is consid-
2.1 ASTM Standards:
ered necessary when an application is susceptible to noise.
B542Terminology Relating to Electrical Contacts andTheir
However, these procedures are not capable of determining the
Use
actual duration of the event detected.
B854GuideforMeasuringElectricalContactIntermittences
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.Thedetectorwillindicatewhentheresistancemonitored
This test method is under the jurisdiction of ASTM Committee B02 on
exceeds the minimum event resistance for more than the
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee
specified duration.
B02.11 on Electrical Contact Test Methods.
Current edition approved April 15, 2009. Published April 2009. Originally
4.6 The test condition designation corresponding to a spe-
approved in 1997. Last previous edition approved in 2003 as B878–97(2003).
cific minimum event duration of 1, 10, or 50 ns is listed in
DOI: 10.1520/B0878-97R09.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B878 − 97(Reapproved 2009)
Table 1. These shall be specified in the referencing document.
B878 − 97 (2009)
TABLE 1 Test Condition Designations for Specific Minimum
5.1.4.1 The same requirements shall be met for the 10 and
Event Durations
50nsdetectorsettings,butthepulseriseandfalltimescannow
Test Condition Event Duration, min
be less than 2 ns.
5.1.5 Accuracy—Itshallbepossibletoadjustthedetectorto
A 1 nanosecond
trip at 10 6 1Ω for all channels in use.
B 10 nanoseconds
C 50 nanoseconds
5.2 Test Setup—Recommended equipment is as shown in
Fig. 2. A short flexible ground strap directs ground loop
currents away from the sample (see Fig. 2, Note E). The
RG-223 coaxial cable is well shielded whereas the short 50Ω
5. Apparatus
miniaturecoaxialcableisflexible.EachEMIloopisconnected
5.1 Detector—The detector used shall be an AnaTech 64
to a detector channel and is used as a control.
EHD, 32 EHD, or equivalent. The detector shall meet the
5.3 Sample and EMI Loop Preparation—Thesamplecircuit
following requirements:
shall have a resistance of less than 4Ω.
5.1.1 Electromagnetic Interference (EMI)—The detector
5.3.1 Sample Wiring:
shall pass the European Community (EC) electrostatic dis-
5.3.1.1 A contact or series-wired contacts (see Fig. 3, Note
charge (ESD) requirement for computers (EN50 082-1:94
A) shall be wired from the center conductor to the braid of
based on IEC801-2, ed. 2:91). The performance criteria is “1)
miniature 50-Ω coaxial cable (see Fig. 2, Note C).
normalperformancewithinthespecificationlimits;”thatis,no
5.3.1.2 The sample, as wired to the miniature coaxial cable
channel is allowed to trip.Air discharge voltages shall include
for testing, shall be capable of passing short duration pulses.A
2, 4, 8, and 15 kV. Contact discharge voltages shall include 2,
time domain reflectometer (TDR) shall be used to measure the
4, 6, and 8 kV. Detector inputs shall be protected with coaxial
transition time of a fast risetime step (<60 ps) reflected from
shorts.
the sample under test. On the waveform, find the point
5.1.2 dc Current—Each channel shall supply 100 6 20 mA
representing the far end of the miniature 50-Ω coaxial cable
whenthesamplebeingtestedhasaresistancebetween0and10
(see Fig. 4, Point 1).Also find the last point on the waveform
Ω.
where the voltage amplitude is 20% of Point 1 (see Fig. 4,
5.1.3 Input Impedance:
Point 2). The time between these points shall be less than the
5.1.3.1 Direct Current (dc)—The detector source resistance
(impedance) shall be 50 Ω when the sample resistance is
between 0 and 10Ω.
5.1.3.2 RF Input Impedance—ATime Domain Reflectome-
ter (TDR) or Network Analyzer Time Domain Reflectometer
(NATDR) shall be used to measure the reflection in percent of
a (simulated) 0.5 ns risetime step when the sample direct
current resistance is 10Ω and the detector current is 100 mA.
(The 10 Ω sample resistance is put on the bias port for
NATDR.) An acceptable detector shall reflect less than 30%
amplitude.
5.1.4 Amplitude Sensitivity—Amplitude required to trip the
detector with a 1 nanosecond duration pulse shall be no more
than 120% of the direct current trip amplitude. One nanosec-
ond pulse duration shall be measured at 90% of the pulse
amplitude, and the rise and fall times shall be less than 0.5 ns.
Pulse low level shall be 0 V. These shall be measured with a 1
GHzbandwidthoscilloscopeandapulsegenerator(seeFig.1).
NOTE 1—
A One square meter EMI loop monitored at top center (see 6.1).
B Connection to series wired sample circuit with the greatest capacitance
shell or other metal fixturing (see 6.1).
C Miniature coaxial cable (50Ω) (see 5.3.1.1).
D Patch panel, coaxial through-bulkhead RF connectors in metal panel.
E Short flexible ground strap, 70 mm long and >25 mm wide (see 7.3).
F Strain relief coaxial cable at these locations.
G Physical support for patch panel.
H RG-223 double braid coaxial cable.
FIG. 1 Equipment Setup for Amplitude Sensitivity Measurement FIG. 2 Ten and Fifty Nanosecond Fixturing
B878 − 97 (2009)
5.3.2.2 Large EMI currents in adjacent contacts can couple
through crosstalk or capacitance to monitored channels. To
reduce this, no conductor of any type may be c
...
This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:B878–97(Reapproved2003) Designation: B 878 – 97 (Reapproved 2009)
Standard Test Method for
Nanosecond Event Detection for Electrical Contacts and
Connectors
This standard is issued under the fixed designation B 878; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
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 V.
1.4 An ASTM guide for measuring electrical contact transients of various durations is available as Guide B 854.
1.5This 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 and health practices and determine the applicability of regulatory
limitations prior to use.
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 and health practices, and
determine the applicability of regulatory limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
B 542 Terminology Relating to Electrical Contacts and Their UseUse
B 854 Guide for Measuring Electrical Contact Intermittences Intermittences
2.2 Other Standards:
IEC 801-2, IEC 801-2 ed 2:91
EN 50 082-1:94
3. Terminology
3.1 Definitions: Many terms used in this standard are defined in Terminology B 542.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 eventevent, n—a condition in which the sample resistance increases by more than 10 V for more than a specified time
duration.
4. Significance and Use
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 (620 mA) when the test sample has a resistance between 0 and 10 V.
Since the minimum resistance change required to produce an event (defined in 3.2.1) is specified as 10 V (see 1.3), the voltage
increase required to produce this event must be at least 1.0 V.
This test method is under the jurisdiction of ASTM Committee B02 on Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee B02.11 on
Electrical Contact Test Methods.
Current edition approved June 10, 2003. Published July 2003. Originally approved in 1997. Last previous edition approved in 1997 as B878-97.
Current edition approved April 15, 2009. Published April 2009. Originally approved in 1997. Last previous edition approved in 2003 as B 878 - 97 (2003).
Annual Book of ASTM Standards, Vol 02.04.
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from American National Standards Institute, 11 W. 42nd St., 13th Floor, New York, NY 10036.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
B 878 – 97 (2009)
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.
5. Apparatus
5.1 Detector—The detector used shall be an AnaTech 64 EHD, 32 EHD, or equivalent. The detector shall meet the following
requirements:
5.1.1 Electromagnetic Interference (EMI)— The detector shall pass the European Community (EC) electrostatic discharge
(ESD) requirement for computers (EN50 082-1:94 (EN 50 082-1:94 based on IEC 801-2, ed. 2:91IEC 801-2, ed. 2:91). The
performance criteria is “1) normal performance within the specification limits;” that is, no channel is allowed to trip.Air discharge
voltages shall include 2, 4, 8, and 15 kV. Contact discharge voltages shall include 2, 4, 6, and 8 kV. Detector inputs shall be
protected with coaxial shorts.
5.1.2 dc Current—Each channel shall supply 100 6 20 mA when the sample being tested has a resistance between 0 and 10
V.
5.1.3 Input Impedance:
5.1.3.1 Direct Current (dc)—The detector source resistance (impedance) shall be 50 V when the sample resistance is between
0 and 10 V.
5.1.3.2 RF Input Impedance—A Time Domain Reflectometer (TDR) or Network Analyzer Time Domain Reflectometer
(NATDR) shall be used to measure the reflection in percent of a (simulated) 0.5 ns risetime step when the sample direct current
resistance is 10 V and the detector current is 100 mA. (The 10 V sample resistance is put on the bias port for NATDR.) An
acceptable detector shall reflect less than 30 % amplitude.
5.1.4 Amplitude Sensitivity—Amplitude required to trip the detector with a 1 nanosecond duration pulse shall be no more than
120 % of the direct current trip amplitude. One nanosecond pulse duration shall be measured at 90 % of the pulse amplitude, and
the rise and fall times shall be less than 0.5 ns. Pulse low level shall be 0 V. These shall be measured with a 1 GHz bandwidth
oscilloscope and a pulse generator (see Fig. 1).
5.1.4.1 The same requirements shall be met for the 10 and 50 ns detector settings, but the pulse rise and fall times can now be
less than 2 ns.
5.1.5 Accuracy—It shall be possible to adjust the detector to trip at 10 6 1 V for all channels in use.
5.2 Test Setup—RecommendedequipmentisasshowninFig.2.Ashortflexiblegroundstrapdirectsgroundloopcurrentsaway
from the sample (see Fig. 2, Note E). The RG-223 coaxial cable is well shielded whereas the short 50 V miniature coaxial cable
is flexible. Each EMI loop is connected to a detector channel and is used as a control.
5.3 Sample and EMI Loop Preparation— The sample circuit shall have a resistance of less than 4 V.
5.3.1 Sample Wiring:
5.3.1.1 Acontact or series-wired contacts (see Fig. 3, NoteA) shall be wired from the center conductor to the braid of miniature
50-V coaxial cable (see Fig. 2, Note C).
5.3.1.2 The sample, as wired to the miniature coaxial cable for testing, shall be capable of passing short duration pulses.Atime
domain reflectometer (TDR) shall be used to measure the transition time of a fast risetime step (<60 ps) reflected from the sample
under test. On the waveform, find the point representing the far end of the miniature 50-V coaxial cable (see Fig. 4, Point 1).Also
find the last point on the waveform where the voltage amplitude is 20 % of Point 1 (see Fig. 4, Point 2). The time between these
points shall be less than the minimum duration of the event identified in Table 1. Each series-wired sample circuit shall be
measured.
5.3.2 Electromagnetic Interference (EMI) Concerns of Sample Wiring—At least three major paths for EMI can be identified in
the sample fixturing.
5.3.2.1 EMI couples to the sample through the parasitic capacitance between the sample and any metal fixturing. To greatly
reducethiscoupling,theminiaturecoaxialcableshieldshallbeconnectedtothemetalfixturingasclosetotheconnector-under-test
as possible.This connection shall be as short as possible and perpendicular to nearby sample conduct
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.