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ASTM B539-02e1

(Test Method)

Standard Test Methods for Measuring Resistance of Electrical Connections (Static Contacts)

Standard Test Methods for Measuring Resistance of Electrical Connections (Static Contacts)

SCOPE
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 establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
1.4 It is the responsibility of the user to become familiar with all hazards including those identified in the appropriate Material Safety Data Sheet for this product/material as provided by the manufacturer.

General Information

Status
Historical
Publication Date
09-May-2002
ICS
29.120.20 - Connecting devices
Technical Committee
B02 - Nonferrous Metals and Alloys
Drafting Committee
B02.11 - Electrical Contact Test Methods
Current Stage
Ref Project

Relations

Replaces
ASTM B539-02 - Standard Test Methods for Measuring Resistance of Electrical Connections (Static Contacts)
Effective Date
10-May-2002
Replaced By
ASTM B539-02(2008) - Standard Test Methods for Measuring Resistance of Electrical Connections (Static Contacts)
Effective Date
01-Mar-2008
Referred By
ASTM B1004-16(2022) - Standard Practice for Contact Performance Classification of Electrical Connection Systems
Effective Date
10-May-2002
Referred By
ASTM B896-10(2020) - Standard Test Methods for Evaluating Connectability Characteristics of Electrical Conductor Materials
Effective Date
10-May-2002
Referred By
ASTM B854-98(2022) - Standard Guide for Measuring Electrical Contact Intermittences
Effective Date
10-May-2002
Referred By
ASTM B942-21 - Standard Guide for Specification and Quality Assurance for the Electrical Contact Performance of Crimped Wire Terminations
Effective Date
10-May-2002
Referred By
ASTM B885-09(2020) - Standard Test Method for Presence of Foreign Matter on Printed Wiring Board Contacts
Effective Date
10-May-2002
Referred By
ASTM B794-97(2020) - Standard Test Method for Durability Wear Testing of Separable Electrical Connector Systems Using Electrical Resistance Measurements
Effective Date
10-May-2002

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ASTM B539-02e1 - Standard Test Methods for Measuring Resistance of Electrical Connections (Static Contacts)ASTM B539-02e1 - Standard Test Methods for Measuring Resistance of Electrical Connections (Static Contacts)
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ASTM B539-02e1 - Standard Test Methods for Measuring Resistance of Electrical Connections (Static Contacts)
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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
e1
Designation: B 539 – 02
Standard Test Methods for
Measuring Resistance of Electrical Connections (Static
1
Contacts)
This standard is issued under the fixed designation B 539; 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 (e) indicates an editorial change since the last revision or reapproval.
1
e NOTE—Editorial changes were made throughout in April 2003.
1. Scope bulk resistance as possible in the measurement, by placing
measuring probes as close to the contact interface as practical.
1.1 These test methods cover equipment and techniques for
3.1.2 connection resistance—the resistance from the termi-
measuringtheresistanceofstaticelectricalconnectionssuchas
nation point on one end of a device containing static contacts,
wire terminations or splices, friction connectors, soldered
through the contacts to the termination point on the other end
joints, and wrapped-wire connections.
of the device. The termination point is the location on a
1.2 Measurements under two distinct levels of electrical
terminal of a device where a wire or printed circuit path
loading are described. These levels are: (1) dry circuit, (2) and
electrically connects to the terminal. This resistance is the
rated current. One or both of these levels of loading may be
value of resistance displayed by the device in a circuit
required in specific cases.
application.
1.3 This standard does not purport to address all of the
3.1.2.1 Discussion—The term contact resistance is often
safety concerns, if any, associated with its use. It is the
used in commercial literature to indicate the connection resis-
responsibility of the user of this standard to become familiar
tance displayed by the device in a standard application. In the
with all hazards including those identified in the appropriate
more rigorous usage of contact resistance, the connection
Material Safety Data Sheet for this product/material as pro-
resistance is the sum of the contact resistance plus the bulk
vided by the manufacturer, to establish appropriate safety and
resistance of leads within the device that go to the static
health practices, and determine the applicability of regulatory
contacts from the point that the leads are connected to the
limitations prior to use.
external circuitry. Measurement of contact resistance indepen-
2. Referenced Documents dent of all bulk resistance is very difficult for most commercial
devices.
2.1 ASTM Standards:
3.1.3 dry circuit—acircuitinwhichthe open-circuitvoltage
B 542 Terminology Relating to Electrical Contacts and
2
is less than or equal to 20 mV. Current is usually low in a dry
Their Use
circuit, but a low-current circuit is not necessarily a dry circuit.
E 122 Practice for Calculating Sample Size to Estimate,
When the applied voltage (open-circuit voltage) is too low to
With a Specified Tolerable Error, the Average for a
3
cause any physical changes in the contact junction, such as
Characteristic of a Lot or Process
break-down of thin insulating films or softening of contact
3. Terminology
asperities, the circuit is said to be a dry circuit.
3.1.4 open-circuit voltage—the steady-state voltage which
3.1 Definitions: see Terminology B 542 for definitions of
would appear across the contacts if they were opened.
contact resistance, film resistance, and constriction resistance.
3.1.5 static contacts—electric junctions designed for infre-
3.1.1 bulk resistance—the resistance a contact assembly
quent separation and connection, and intended to perform their
would have if it were solid metal of an identical geometry so
function only when contacting members are stationary relative
that the nominal contact area offered zero resistance. When
toeachother.Thisdefinitionincludescrimped,welded,brazed,
measuring contact resistance one attempts to include as little
riveted, or soldered joints; friction connections such as pin and
socket connectors or taper pins, twisted-wire splices; and
1
These test methods are under the jurisdiction of ASTM Committee B02 on
connections made with screws, or bolts and nuts between
Nonferrous Metals and Alloys and are the direct responsibility of Subcommittee
electrical wiring and components. The definition excludes
B02.11 on Electrical Contact Test Methods.
relay contacts, slip rings and commutators, and switches and
Current edition approved May 10, 2002. Published July 2002. Originally
published as B 539 – 70. Last previous edition B 539 – 01. circuit breakers.
2
Annual Book of ASTM Standards, Vol 02.04.
3
Annual Book of ASTM Standards, Vol 14.02.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

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1.3.1 This test method shall not be considered to confirm a specific lifetime in application environments.  
1.3.2 The applicability of this test method is limited to pressure connection systems rated at or below 600 V d-c or a-c RMS.  
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1.3.4 This test method does not evaluate degradation which may occur in residential applications due to exposure of the electrical connection system to additional environmental constituents such as (but not limited to) the following examples:
1.3.4.1 Household chemicals (liquid or gaseous) such as ammonia, bleach, or other cleaning agents.
1.3.4.2 Chemicals as may occur due to normal hobby or professional activities such as photography, painting, sculpture, or similar activities.
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