IEC 60512-99-002:2022
(Main)Connectors for electrical and electronic equipment - Tests and measurements - Part 99-002: Endurance test schedules - Test 99b: Test schedule for unmating under electrical load
Connectors for electrical and electronic equipment - Tests and measurements - Part 99-002: Endurance test schedules - Test 99b: Test schedule for unmating under electrical load
IEC 60512-99-002:2021 is used for the assessment of connectors within the scope of SC 48B that are used in twisted pair communication cabling with remote power, such as ISO;IEC 11801 1 Class D, or better, balanced cabling in support of IEEE 802.3btTM (Power over Ethernet, supporting up to 90 W from the power sourcing equipment).
The object of this document is to detail a test schedule to determine the ability of sets of connectors to withstand a minimum of 100 mechanical operations with electrical load, where an electrical current is being passed through the connectors in accordance with IEC 60512 9 3 during the separation (unmating) step. This second edition cancels and replaces the first edition published in 2019. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: Test group UEL has been revised with respect to the order of the test phases, the test severities and the requirements.
Connecteurs pour équipements électriques et électroniques - Essais et mesures - Partie 99-002: Programmes d’essais d’endurance – Essai 99b: Programme d’essai pour le désaccouplement sous charge électrique
L’IEC 60512 est utilisée pour évaluer des connecteurs relevant du domaine d’application du SC 48B, qui sont utilisés dans les câblages de communication à paires torsadées permettant une alimentation à distance, tels que les câbles à paires symétriques conformes à la classe D de l’ISO/IEC 11801‑1 ou à une classe supérieure, à l’appui de la norme IEEE 802.3btTM (Power over Ethernet (alimentation électrique par câble Ethernet), prenant en charge jusqu’à 90 W provenant de l’équipement de source d’alimentation). L’objet du présent document est de détailler un programme d’essai permettant de déterminer l’aptitude des jeux de connecteurs à supporter au moins 100 manœuvres mécaniques avec charge électrique lorsqu’un courant électrique traverse les connecteurs conformément à l’IEC 60512‑9‑3 pendant la séparation (désaccouplement). Cette deuxième édition annule et remplace la première édition publiée en 2019. Cette édition constitue une révision technique. Cette édition comprend les modifications techniques importantes suivantes par rapport à l’édition précédente : Le groupe d’essai UEL a été révisé en ce qui concerne l’ordre des phases de test, les sévérités des tests et les exigences.
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IEC 60512-99-002 ®
Edition 2.0 2022-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Connectors for electrical and electronic equipment – Tests and measurements –
Part 99-002: Endurance test schedules – Test 99b: Test schedule for unmating
under electrical load
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IEC 60512-99-002 ®
Edition 2.0 2022-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Connectors for electrical and electronic equipment – Tests and measurements –
Part 99-002: Endurance test schedules – Test 99b: Test schedule for unmating
under electrical load
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.220.10 ISBN 978-2-8322-4195-0
– 2 – IEC 60512-99-002:2022 RLV © IEC 2022
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 General . 6
5 Preparation of specimens . 6
6 Test circuit requirements . 7
6.1 General . 7
6.2 Voltage and current . 9
6.3 Auxiliary equipment . 9
7 Test methods . 10
7.1 Initial cycles Mechanical operations with electrical load . 10
7.2 Flowing mixed gas corrosion . 10
7.3 Final cycles .
8 Tests and test schedule – Test group UEL 1 . 10
Annex A (informative) Test voltage and current setting instructions. 14
A.1 General . 14
A.2 Rationale . 14
A.3 Suggested setting instructions . 14
Bibliography . 15
Figure 1 – Test circuit details . 8
Table 1 – Maximum electrical circuit current .
Table 1 – Test group UEL 1 . 11
Table A.1 – Maximum electrical circuit current per IEEE 802.3. 14
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CONNECTORS FOR ELECTRICAL AND ELECTRONIC EQUIPMENT –
TESTS AND MEASUREMENTS –
Part 99-002: Endurance test schedules –
Test 99b: Test schedule for unmating under electrical load
FOREWORD
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rights. IEC shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes made to
the previous edition IEC 60512-99-002:2019. A vertical bar appears in the margin wherever a
change has been made. Additions are in green text, deletions are in strikethrough red text.
– 4 – IEC 60512-99-002:2022 RLV © IEC 2022
IEC 60512-99-002 has been prepared by subcommittee 48B: Electrical connectors, of IEC
technical committee 48: Electrical connectors and mechanical structures for electrical and
electronic equipment. It is an International Standard.
This second edition cancels and replaces the first edition published in 2019. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Test group UEL has been revised with respect to the order of the test phases, the test
severities and the requirements.
The text of this International Standard is based on the following documents:
Draft Report on voting
48B/2922/FDIS 48B/2938/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 60512 series, published under the general title Connectors for
electrical and electronic equipment – Tests and measurements, can be found on the IEC
website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates that it
contains colours which are considered to be useful for the correct understanding of its
contents. Users should therefore print this document using a colour printer.
CONNECTORS FOR ELECTRICAL AND ELECTRONIC EQUIPMENT –
TESTS AND MEASUREMENTS –
Part 99-002: Endurance test schedules –
Test 99b: Test schedule for unmating under electrical load
1 Scope
This part of IEC 60512 is used for testing the assessment of connectors within the scope of
SC 48B that are used in twisted pair communication cabling with remote power, such as
ISO/IEC 11801-1 Class D, or better, balanced cabling in support of IEEE Std 802.3bt™, (PoE
TM
Plus – Power over Ethernet Plus) IEEE 802.3bt (Power over Ethernet, supporting up to 90 W
from the power sourcing equipment).
The object of this document is to detail a test schedule to determine the ability of pairs sets of
connectors to withstand a sequence of tests with a total of 100 engagements and separations.
The electrical current is passed through the connectors during the separation (unmating) step
only, in accordance with IEC 60512-9-3 minimum of 100 mechanical operations with electrical
load, where an electrical current is being passed through the connectors in accordance with
IEC 60512-9-3 during the separation (unmating) step.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60512-1-1, Connectors for electronic equipment – Tests and measurements – Part 1-1:
General examination – Test 1a: Visual examination
IEC 60512-2-1, Connectors for electronic equipment – Tests and measurements – Part 2-1:
Electrical continuity and contact resistance tests – Test 2a: Contact resistance – Millivolt level
method
IEC 60512-3-1, Connectors for electronic equipment – Tests and measurements – Part 3-1:
Insulation tests – Test 3a: Insulation resistance
IEC 60512-4-1, Connectors for electronic equipment – Tests and measurements – Part 4-1:
Voltage stress tests – Test 4a: Voltage proof
IEC 60512-9-3:2011, Connectors for electronic equipment – Tests and measurements –
Part 9‑3: Endurance tests – Test 9c: Mechanical operation (engaging and separating) with
electrical load
IEC 60512-11-7, Connectors for electronic equipment – Tests and measurements – Part 11-7:
Climatic tests – Test 11g: Flowing mixed gas corrosion test
IEC 60512-99-001, Connectors for electronic equipment – Tests and measurements –
Part 99-001: Test schedule for engaging and separating connectors under electrical load – Test
99a: Connectors used in twisted pair communication cabling with remote power
ISO/IEC 11801(all parts): Information technology – Generic cabling for customer premises
– 6 – IEC 60512-99-002:2022 RLV © IEC 2022
ISO/IEC TS 29125: 2017, Information technology – Telecommunications cabling requirements
for remote powering of terminal equipment
TIA-568-A:1995, Commercial building telecommunications cabling standard
TIA-568-B.2:2001, Commercial building telecommunications cabling standard, Part 2: Balanced
twisted-pair cabling components
TIA TSB-184-A:2017, Guidelines for supporting power delivery over balanced twisted-pair
cabling
IEEE Std 802.3™-2018, IEEE Standard for Ethernet
IEEE Std 802.3bt™-2018, IEEE Standard for Ethernet. Amendment 2: Physical Layer and
Management Parameters for Power over Ethernet over 4 pairs
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 General
An application-specific current and the associated open circuit voltage are specified, that
correspond with the current and voltage of the supported application. This test schedule is
suitable for verification of separating of connectors under PoE Plus load conditions; although it
is a misuse of the connector, it may occur in practice.
As it is recognized that not all connectors will see these currents and voltage, this test schedule
is regarded as an optional test, not normative for all connectors.
Although separating (unmating) connectors under the scope of this document, while used for
remote powering, is a misuse of the connector, it may occur in practice.
This test schedule is suitable for verification of separating (unmating) of connectors under load
TM
conditions representative for Power over Ethernet Type 4 as specified per IEEE 802.3bt . An
application-specific current and the associated open circuit voltage are specified, that
correspond with the current and voltage of the supported application.
5 Preparation of specimens
Each specimen shall consist of a mated set of connectors pair with its terminations. Specimens
shall be conformant conform to their relevant IEC connector standard. Each free and each fixed
connector shall be terminated with 3 m (max.) of the maximum conductor size cable for which
it is intended to be terminated, according to the appropriate IEC standard(s). A printed circuit
board may be used for the fixed connectors, so as not to influence the test results. Fixed
connectors may alternatively be terminated as the free ones using a printed circuit board which
shall not influence the test results.
For each specimen, all circuits (mated contacts) shall be wired in parallel as given in
IEC 60512-9-3, (see Figure 1), and all circuits shall be tested.
6 Test circuit requirements
6.1 General
The values for the circuit components and the details of the test circuit, referenced in
IEC 60512-9-3, shall be as shown in Figure 1.
– 8 – IEC 60512-99-002:2022 RLV © IEC 2022
Q1
L1
W
C1
R1
S1
E1
IEC
Key
W Cables in accordance with 5
Q1 Connector under test
L1 Inductor L = 100 μH
R1 Variable resistor (e.g. 50 Ω to 300 Ω)
C1
Capacitor 5 µF
E1 Voltage source
S1 Switch
Key
W Cables in accordance with Clause 5
Q1 Specimen under test
L1 Inductor, L = 100 μH
R1 Variable resistor (e.g. R = 25 Ω to 300 Ω)
C1 Capacitor, C = 5 µF
E1 Voltage source
S1 Switch
Figure 1 – Test circuit details
NOTE 1 Only one circuit of the connector specimen under test, as referenced in IEC 60512-9-3, is shown for clarity.
Items W, Q1, L1, R1 and C1 are replicated for each circuit of the connector specimen. Items E1 and S1 may be
single or multiple. All circuits of the specimen are wired in parallel with appropriate duplication of circuit components,
and all circuits of the specimen are operated simultaneously.
NOTE 2 The variable resistor is used to adjust the current to the specified value.
Each circuit of the specimen may be wired in parallel with the other circuits of the specimen,
and all circuits of each specimen shall operate simultaneously. The variable resistor(s) shall be
used to adjust the current(s) to the specified value.
6.2 Voltage and current
ISO/IEC TS 29125 specifies a maximum current as shown in Table 1 and an open circuit voltage
of 55 V DC. The test current has been set to 2,0 A because a maximum of 4 contact pairs can
be connected in parallel. In the highly probable case that one contact is separated after all
others, this contact will carry this 2,0 A just before disconnecting.
As the resistive load is likely to rise due to heating and due to wear of contacts in the connector
under test, care should be placed in keeping the value of test current within the specified
tolerance range e.g. by means of a suitable feedback control circuit acting on the value of the
variable resistor. See Annex A (informative) for further guidance.
The test procedures for Type 1 and Type 2 are defined in IEC 60512-99-001. For Type 3 and
Type 4 the variable resistor(s) shall be set so that the electrical current in each circuit (mated
+0,05
contacts) of the specimen is 2,0 A . When the specimen is unmated, the open circuit
+1
voltage, in all circuits, shall be 55 V DC V DC. When the specimen is mated, the open circuit
voltage, in all circuits, shall be 0 V DC by operating the switch, S1, before each connector
engagement (mating).
Table 1 – Maximum electrical circuit current
PSE Type Nominal highest Number of Channel pairset Minimum cabling type
current per pair powered maximum DC loop
(I ,A) pairs resistance (R ,Ω)
Cable Ch
Type 1 0,350 2 20,0 Class D (ISO/IEC 11801) or Category 5
(ANSI/EIA/TIA-568-A: 1995)
Type 2 0,600 2 12,5 Class D (ISO/IEC 11801) or Category 5
(ANSI/EIA/TIA-568-A: 1995)
Type 3 0,600 2 or 4 12,5 Class D (ISO/IEC 11801) or Category 5
(ANSI/EIA/TIA-568-B.2:
2001)
Type 4 0,960 2 or 4 12,5 Class D (ISO/IEC 11801) or Category 5
(ANSI/EIA/TIA-568-B.2: 2001)
In Type 3 and Type 4 operation, the current per pairset may be impacted by pair-to-pair system
resistance unbalance. See 33.2.8.5.1 of ISO/IEC TS 29125:2017. For additional information on
Type 4 current unbalance, see TIA TSB-184-A and ISO/IEC TS 29125.
The variable resistor(s) shall be set so that the electrical current in each circuit (mated contacts)
+0,05
of the specimen is 2,0 A. During the separation (unmating) step, the open circuit voltage,
+1
in all circuits, shall be 55 V DC. During the engagement (mating) step, the open circuit
voltage, in all circuits, shall be 0 V DC by operating the switch, S1, before each connector
engagement (mating).
IEEE 802.3™-2018 and IEEE 802.3bt™ specify Power over Ethernet systems with a nominal
highest current per pair depending on the type of power sourcing equipment (PSE) and the
number of powered pairs, and with an open circuit voltage of 55 V DC.
– 10 – IEC 60512-99-002:2022 RLV © IEC 2022
For PSE Type 4, the nominal highest current per pair is 0,96 A when all four pairs are powered,
giving a total source current of 1,92 A. The test current per contact has been set to 2,0 A to
represent the highly probable case that one contact is separated after all others, causing this
contact to carry the full current just before disconnecting.
As the resistive load is likely to rise due to heating and due to wear of contacts in the connector
under test, care should be placed in keeping the value of test current within the specified
tolerance range, e.g. by means of a suitable feedback control circuit acting on the value of the
variable resistor. See Annex A (informative) for further guidance.
6.3 Auxiliary equipment
Switches may be used to reverse polarity. However, use of such switches shall not influence
the test parameters.
7 Test methods
7.1 Initial cycles Mechanical operations with electrical load
An electrical load, current and open circuit voltage, as detailed in 6.2, shall be applied to each
specimen during the separation step only.
For the purpose of this test, one connector shall be fixed and the other disengaged at a speed
of 150 mm/s ± 10 mm/s.
One engagement and one separation constitute one cycle.
25 cycles at one polarity of the DC source shall be performed. The polarity of the DC source
shall then be reversed and 25 further cycles at the other polarity shall be performed (50 cycles
total). The electrical current shall be applied during the separation step only.
7.2 Flowing mixed gas corrosion
The flowing mixed gas corrosion test (method 1) shall be performed for according to IEC 60512-
11-7, method 1, with a test duration of 4 days. Half of the samples mated; half of the samples
unmated.
Half of the specimens shall be unmated and the other half shall be left mated during the test.
7.3 Final cycles
25 cycles at one polarity of the DC source shall be performed. And then the polarity of the DC
source shall be reversed, and 25 further cycles at the other polarity shall be performed
(50 additional cycles total). The electrical current shall be applied during the separation step
only.
8 Tests and test schedule – Test group UEL 1
A minimum of 8 specimens shall be prepared for this group; then tested according to Table 1.
Table 1 – Test group UEL 1
Test Measurement to be performed
Test
Title IEC 60512 Severity or Title IEC 60512 Requirements
phase
test No. condition of test test No.
UEL General Visual 1-1 There shall be
1.1 examination examination no defects that
would impair
normal operation
UEL Contact 2-1 As specified in
1.2 resistance- the relevant
Millivolt connector
level standard
method
UEL Insulation As specified in
100 V DC 3-1
1.3 resistance the relevant
Method A
connector
standard
Mated connectors
UEL Contact to contact Voltage 4-1 There shall be
1.4 proof no break down
1 000 V DC. or
or no flashover
1 500 V AC peak.
All signal contacts to
shield and test
panel, as applicable
Method A
Mated connectors
UEL Mechanical 9-3 Per 7.1 .
1.5 operations
with electrical
load
UEL Flowing 11-7 Per 7.2: Method 1,
1.6 mixed gas
4 days
test
UEL Mechanical 9-3 Per 7.3
1.7 operations
with electrical
load
UEL Contact 2-1 As specified in
1.8 resistance- the relevant
Millivolt connector
level standard
method
UEL General Visual 1-1 There shall be
1.9 examination examination no defects that
would impair
normal
operation.
However,
physical
deterioration of
the contacts may
be observed.
Such
deterioration
shall not be
cited as a failure
of this test.
UEL Contact resistance Contact 2-1 As specified in
1.10 resistance- the relevant
Millivolt connector
level standard
method
UEL 100 V DC Method A Insulation 3-1 500 MΩ
1.11 Mated connectors resistance minimum
– 12 – IEC 60512-99-002:2022 RLV © IEC 2022
Test Measurement to be performed
Test
Title IEC 60512 Severity or Title IEC 60512 Requirements
phase
test No. condition of test test No.
UEL Contact to contact Voltage 4-1 There shall be
1.12 proof no break down
1 000 V DC or
or no flashover
1 500 V AC peak.
All signal contacts to
shield and test
panel, as applicable
Method A
Mated connectors
Test Measurement to be performed
Test
Title IEC 60512 Severity or Title IEC 60512 Requirements
phase
test No. condition of test test No.
UEL General Visual 1a There shall be
1.1 examination examination no defects that
would impair
normal operation
UEL Contact 2a As specified in
1.2 resistance- the relevant
Millivolt connector
level standard
method
UEL 100 V DC Insulation 3a 500 MΩ
1.3 resistance minimum
Method A
Mated connectors
UEL
Contact to contact Voltage 4a There shall be
1.4 proof no breakdown or
1 000 V DC or
flashover
1 000 V AC peak.
All signal contacts to
shield and test
panel, as applicable
1 500 V DC or
1 500 V AC peak.
Method A
Mated connectors
UEL Mechanical 9c Per 7.1 .
1.5 operations
with electrical
load
UEL Flowing 11g Per 7.2
1.6 mixed gas
corrosion test
UEL Contact 2a 20 mΩ maximum
1.7 resistance- change from
Millivolt initial
level
method
UEL Mechanical 9c Per 7.1
1.8 operations
with electrical
load
UEL Contact 20 mΩ maximum
Contact resistance 2a
1.9 resistance- change from
Millivolt initial
level
method
Test Measurement to be performed
Test
Title IEC 60512 Severity or Title IEC 60512 Requirements
phase
test No. condition of test test No.
UEL 100 V DC Insulation 3a 500 MΩ
1.10
resistance minimum
Method A
Mated connectors
UEL Contact to contact Voltage 4a There shall be
1.11 proof no breakdown or
1 000 V DC or
flashover
1 000 V AC peak.
All signal contacts to
shield and test
panel, as applicable
1 500 V DC or
1 500 V AC peak.
Method A
Mated connectors
UEL General Visual 1a There shall be
1.12 examination examination no defects that
would impair
normal
operation.
However,
physical
deterioration of
the contacts may
be observed.
Such
deterioration
shall not be
cited as a failure
of this test.
– 14 – IEC 60512-99-002:2022 RLV © IEC 2022
Annex A
(informative)
Test voltage and current setting instructions
A.1 General
IEEE 802.3™-2018 and IEEE 802.3bt™ specify Power over Ethernet systems with a nominal
highest current per pair as shown in Table A.1 and an open circuit voltage of 55 V DC. A test
procedure for connectors for use with Type 1 and Type 2 is defined in IEC 60512-99-001.
Table A.1 – Maximum electrical circuit current per IEEE 802.3
PSE type Nominal highest current per pair Number of powered pairs
A
Type 1 0,350 2
Type 2 0,600 2
Type 3 0,6 2 or 4
Type 4 0,6 2
Type 4 0,96 4
It is possible that confusion as to how to set the required voltages and currents may arise. Given
below are a set of informative instructions as to how this may be achieved.
A.2 Rationale
The open circuit voltage requirement is stated such that during unmating under load, the stated
voltage is available to ‘drive’ arcing.
Some power sources have an ‘open circuit’ setting which is used to clamp the voltage to prevent
an over voltage condition. As no source voltage is stated for the supply in a constant voltage
mode, an interpretation of the requirements could be to set some level of source voltage (the
DC supply constant voltage setting) below, e.g., 55 V, and to set the maximum open circuit
voltage at, e.g., 55 V. But, under this interpretation, upon unmating the constant voltage setting
would not allow the voltage to reach the intended open circuit level.
A.3 Suggested setting instructions
The DC source voltage and variable resistors should be adjusted such that the current in each
circuit (each mated pair of contacts within the connector under test) is the required value (e.g.
1,0 2,0 A) when mated and the open circuit voltage is the required value (e.g. 55 V) when
unmated. For each test circuit the suggested setting instructions are as follows.
a) With the DC power supply off and all variable resistors adjusted at a suitably high value
(e.g. 200 Ω), perform the initial mating of the connector.
b) Place the power supply in a constant voltage mode with the voltage adjustment set at 0 V,
and the current adjustment at its maximum setting.
c) Turn on the power supply.
d) Adjust the constant voltage setting to the required voltage.
e) Reduce the resistance of the variable resistor in each circuit until the required current value
is flowing in the circuit being adjusted.
Bibliography
IEC TR 62652, Effects of engaging and separating under electrical load on connector interfaces
in cabling used to support IEEE 802.3af (power-over-ethernet) applications
IEEE 802.3 Standard for Information technology – Telecommunications and information
exchange between systems — Local and metropolitan area networks – Specific requirements
– Part 3: Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method
and Physical Layer Specifications – Amendment 3: Data Terminal Equipment (DTE) – Power
via the Media Dependent Interface (MDI) Enhancements
IEC 60512-99-001, Connectors for electronic equipment – Tests and measurements –
Part 99‑001: Test schedule for engaging and separating connectors under electrical load –
Test 99a: Connectors used in twisted pair communication cabling with remote power
ISO/IEC 11801-1: Information technology – Generic cabling for customer premises – Part 1:
General requirements
___________
IEC 60512-99-002 ®
Edition 2.0 2022-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Connectors for electrical and electronic equipment – Tests and measurements –
Part 99-002: Endurance test schedules – Test 99b: Test schedule for unmating
under electrical load
Connecteurs pour équipements électriques et électroniques – Essais et
mesures –
Partie 99-002: Programmes d’essais d’endurance – Essai 99b: Programme
d’essai pour le désaccouplement sous charge électrique
– 2 – IEC 60512-99-002:2022 © IEC 2022
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 General . 6
5 Preparation of specimens . 6
6 Test circuit requirements . 6
6.1 General . 6
6.2 Voltage and current . 7
6.3 Auxiliary equipment . 8
7 Test methods . 8
7.1 Mechanical operations with electrical load . 8
7.2 Flowing mixed gas corrosion . 8
8 Tests and test schedule – Test group UEL 1 . 8
Annex A (informative) Test voltage and current setting instructions. 11
A.1 General . 11
A.2 Rationale . 11
A.3 Suggested setting instructions . 11
Bibliography . 12
Figure 1 – Test circuit details . 7
Table 1 – Test group UEL 1 . 9
Table A.1 – Maximum electrical circuit current per IEEE 802.3. 11
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CONNECTORS FOR ELECTRICAL AND ELECTRONIC EQUIPMENT –
TESTS AND MEASUREMENTS –
Part 99-002: Endurance test schedules –
Test 99b: Test schedule for unmating under electrical load
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 60512-99-002 has been prepared by subcommittee 48B: Electrical connectors, of IEC
technical committee 48: Electrical connectors and mechanical structures for electrical and
electronic equipment. It is an International Standard.
This second edition cancels and replaces the first edition published in 2019. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Test group UEL has been revised with respect to the order of the test phases, the test
severities and the requirements.
– 4 – IEC 60512-99-002:2022 © IEC 2022
The text of this International Standard is based on the following documents:
Draft Report on voting
48B/2922/FDIS 48B/2938/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 60512 series, published under the general title Connectors for
electrical and electronic equipment – Tests and measurements, can be found on the IEC
website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
CONNECTORS FOR ELECTRICAL AND ELECTRONIC EQUIPMENT –
TESTS AND MEASUREMENTS –
Part 99-002: Endurance test schedules –
Test 99b: Test schedule for unmating under electrical load
1 Scope
This part of IEC 60512 is used for the assessment of connectors within the scope of SC 48B
that are used in twisted pair communication cabling with remote power, such as
TM
ISO/IEC 11801-1 Class D, or better, balanced cabling in support of IEEE 802.3bt (Power over
Ethernet, supporting up to 90 W from the power sourcing equipment).
The object of this document is to detail a test schedule to determine the ability of sets of
connectors to withstand a minimum of 100 mechanical operations with electrical load, where an
electrical current is being passed through the connectors in accordance with IEC 60512-9-3
during the separation (unmating) step.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60512-1-1, Connectors for electronic equipment – Tests and measurements – Part 1-1:
General examination – Test 1a: Visual examination
IEC 60512-2-1, Connectors for electronic equipment – Tests and measurements – Part 2-1:
Electrical continuity and contact resistance tests – Test 2a: Contact resistance – Millivolt level
method
IEC 60512-3-1, Connectors for electronic equipment – Tests and measurements – Part 3-1:
Insulation tests – Test 3a: Insulation resistance
IEC 60512-4-1, Connectors for electronic equipment – Tests and measurements – Part 4-1:
Voltage stress tests – Test 4a: Voltage proof
IEC 60512-9-3, Connectors for electronic equipment – Tests and measurements – Part 9‑3:
Endurance tests – Test 9c: Mechanical operation (engaging and separating) with electrical load
IEC 60512-11-7, Connectors for electronic equipment – Tests and measurements – Part 11-7:
Climatic tests – Test 11g: Flowing mixed gas corrosion test
IEEE Std 802.3™-2018, IEEE Standard for Ethernet
IEEE Std 802.3bt™-2018, IEEE Standard for Ethernet. Amendment 2: Physical Layer and
Management Parameters for Power over Ethernet over 4 pairs
– 6 – IEC 60512-99-002:2022 © IEC 2022
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 General
Although separating (unmating) connectors under the scope of this document, while used for
remote powering, is a misuse
...
IEC 60512-99-002 ®
Edition 2.1 2025-04
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
Connectors for electrical and electronic equipment – Tests and measurements –
Part 99-002: Endurance test schedules – Test 99b: Test schedule for unmating
under electrical load
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
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IEC 60512-99-002 ®
Edition 2.1 2025-04
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
T Connectors for electrical and electronic equipment – Tests and measurements –
Part 99-002: Endurance test schedules – Test 99b: Test schedule for unmating
under electrical load
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.220.10 ISBN 978-2-8327-0358-8
REDLINE VERSION – 2 – IEC 60512-99-002:2022+AMD1:2025 CSV
© IEC 2025
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 General . 6
5 Preparation of specimens . 6
6 Test circuit requirements . 6
6.1 General . 6
6.2 Voltage and current . 7
6.3 Auxiliary equipment . 8
7 Test methods . 8
7.1 Mechanical operations with electrical load . 8
7.2 Flowing mixed gas corrosion . 8
8 Tests and test schedule – Test group UEL 1 . 8
Annex A (informative) Test voltage and current setting instructions. 11
A.1 General . 11
A.2 Rationale . 11
A.3 Suggested setting instructions . 11
Bibliography . 12
Figure 1 – Test circuit details . 7
Table 1 – Test group UEL 1 . 9
Table A.1 – Maximum electrical circuit current per IEEE 802.3. 11
© IEC 2025
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CONNECTORS FOR ELECTRICAL AND ELECTRONIC EQUIPMENT –
TESTS AND MEASUREMENTS –
Part 99-002: Endurance test schedules –
Test 99b: Test schedule for unmating under electrical load
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) [IEC/IEC and ISO] [draws/draw] attention to the possibility that the implementation of this document may involve
the use of (a) patent(s). [IEC/IEC and ISO] [takes/take] no position concerning the evidence, validity or
applicability of any claimed patent rights in respect thereof. As of the date of publication of this document,
[IEC/IEC and ISO] [had/had not] received notice of (a) patent(s), which may be required to implement this
document. However, implementers are cautioned that this may not represent the latest information, which may
be obtained from the patent database available at https://patents.iec.ch [and/or] www.iso.org/patents. [IEC/IEC
and ISO] shall not be held responsible for identifying any or all such patent rights.
This consolidated version of the official IEC Standard and its amendment has been
prepared for user convenience.
IEC 60512-99-002 edition 2.1 contains the second edition (2022-01) [documents
48B/2922/FDIS and 48B/2938/RVD] and its amendment 1 (2025-04) [documents
48B/3106/CDV and 48B/3125/RVC].
In this Redline version, a vertical line in the margin shows where the technical content is
modified by amendment 1. Additions are in green text, deletions are in strikethrough red
text. A separate Final version with all changes accepted is available in this publication.
REDLINE VERSION – 4 – IEC 60512-99-002:2022+AMD1:2025 CSV
© IEC 2025
IEC 60512-99-002 has been prepared by subcommittee 48B: Electrical connectors, of IEC
technical committee 48: Electrical connectors and mechanical structures for electrical and
electronic equipment. It is an International Standard.
This second edition cancels and replaces the first edition published in 2019. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Test group UEL has been revised with respect to the order of the test phases, the test
severities and the requirements.
The text of this International Standard is based on the following documents:
Draft Report on voting
48B/2922/FDIS 48B/2938/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 60512 series, published under the general title Connectors for
electrical and electronic equipment – Tests and measurements, can be found on the IEC
website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
© IEC 2025
CONNECTORS FOR ELECTRICAL AND ELECTRONIC EQUIPMENT –
TESTS AND MEASUREMENTS –
Part 99-002: Endurance test schedules –
Test 99b: Test schedule for unmating under electrical load
1 Scope
This part of IEC 60512 is used for the assessment of connectors within the scope of SC 48B
that are used in twisted pair communication cabling with remote power, such as
TM
ISO/IEC 11801-1 Class D, or better, balanced cabling in support of IEEE 802.3bt (Power over
Ethernet, supporting up to 90 W from the power sourcing equipment).
The object of this document is to detail a test schedule to determine the ability of sets of
connectors to withstand a minimum of 100 mechanical operations with electrical load, where an
electrical current is being passed through the connectors in accordance with IEC 60512-9-3
during the separation (unmating) step.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60512-1-1, Connectors for electronic equipment – Tests and measurements – Part 1-1:
General examination – Test 1a: Visual examination
IEC 60512-2-1, Connectors for electronic equipment – Tests and measurements – Part 2-1:
Electrical continuity and contact resistance tests – Test 2a: Contact resistance – Millivolt level
method
IEC 60512-3-1, Connectors for electronic equipment – Tests and measurements – Part 3-1:
Insulation tests – Test 3a: Insulation resistance
IEC 60512-4-1, Connectors for electronic equipment – Tests and measurements – Part 4-1:
Voltage stress tests – Test 4a: Voltage proof
IEC 60512-9-3, Connectors for electronic equipment – Tests and measurements – Part 9‑3:
Endurance tests – Test 9c: Mechanical operation (engaging and separating) with electrical load
IEC 60512-11-7, Connectors for electronic equipment – Tests and measurements – Part 11-7:
Climatic tests – Test 11g: Flowing mixed gas corrosion test
IEEE Std 802.3™-2018, IEEE Standard for Ethernet
IEEE Std 802.3bt™-2018, IEEE Standard for Ethernet. Amendment 2: Physical Layer and
Management Parameters for Power over Ethernet over 4 pairs
REDLINE VERSION – 6 – IEC 60512-99-002:2022+AMD1:2025 CSV
© IEC 2025
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 General
Although separating (unmating) connectors under the scope of this document, while used for
remote powering, is a misuse of the connector, it may occur in practice.
This test schedule is suitable for verification of separating (unmating) of connectors under load
TM
conditions representative for Power over Ethernet Type 4 as specified per IEEE 802.3bt . An
application-specific current and the associated open circuit voltage are specified, that
correspond with the current and voltage of the supported application.
5 Preparation of specimens
Each specimen shall consist of a mated set of connectors with its terminations. Specimens shall
conform to the relevant IEC connector standard. Each free and each fixed connector shall be
terminated with 3 m (max.) of the maximum conductor size cable for which it is intended to be
terminated, according to the appropriate IEC standard(s). Fixed connectors may alternatively
be terminated using a printed circuit board which shall not influence the test results.
For each specimen, all circuits (mated contacts) shall be wired in parallel as given in
IEC 60512-9-3, and all circuits shall be tested.
6 Test circuit requirements
6.1 General
The values for the circuit components and the details of the test circuit, referenced in
IEC 60512-9-3, shall be as shown in Figure 1.
© IEC 2025
Key
W Cables in accordance with Clause 5
Q1 Specimen under test
L1 Inductor, L = 100 μH
R1 Variable resistor (e.g. R = 25 Ω to 300 Ω)
C1 Capacitor, C = 5 µF
E1 Voltage source
S1 Switch
Figure 1 – Test circuit details
NOTE 1 Only one circuit of the specimen under test, as referenced in IEC 60512-9-3, is shown for clarity. Items W,
L1, R1 and C1 are replicated for each circuit of the specimen. Items E1 and S1 may be single or multiple. All circuits
of the specimen are wired in parallel with appropriate duplication of circuit components, and all circuits of the
specimen are operated simultaneously.
NOTE 2 The variable resistor is used to adjust the current to the specified value.
6.2 Voltage and current
The variable resistor(s) shall be set so that the electrical current in each circuit (mated contacts)
+0,05
of the specimen is 2,0 A. During the separation (unmating) step, the open circuit voltage,
+1
in all circuits, shall be 55 V DC. During the engagement (mating) step, the open circuit
voltage, in all circuits, shall be 0 V DC by operating the switch, S1, before each connector
engagement (mating).
IEEE 802.3™-2018 and IEEE 802.3bt™ specify Power over Ethernet systems with a nominal
highest current per pair depending on the type of power sourcing equipment (PSE) and the
number of powered pairs, and with an open circuit voltage of 55 V DC.
For PSE Type 4, the nominal highest current per pair is 0,96 A when all four pairs are powered,
giving a total source current of 1,92 A. The test current per contact has been set to 2,0 A to
represent the highly probable case that one contact is separated after all others, causing this
contact to carry the full current just before disconnecting.
As the resistive load is likely to rise due to heating and due to wear of contacts in the connector
under test, care should be placed in keeping the value of test current within the specified
tolerance range, e.g. by means of a suitable feedback control circuit acting on the value of the
variable resistor. See Annex A (informative) for further guidance.
REDLINE VERSION – 8 – IEC 60512-99-002:2022+AMD1:2025 CSV
© IEC 2025
6.3 Auxiliary equipment
Switches may be used to reverse polarity. However, use of such switches shall not influence
the test parameters.
7 Test methods
7.1 Mechanical operations with electrical load
An electrical load, current and open circuit voltage, as detailed in 6.2, shall be applied to each
specimen.
For the purpose of this test, one connector shall be fixed and the other disengaged at a speed
of 150 mm/s ± 10 mm/s.
One engagement and one separation constitute one cycle.
25 cycles at one polarity of the DC source shall be performed. The polarity of the DC source
shall then be reversed and 25 further cycles at the other polarity shall be performed (50 cycles
total). The electrical current shall be applied during the separation step only.
7.2 Flowing mixed gas corrosion
The flowing mixed gas corrosion test shall be performed according to IEC 60512-11-7, method
1, with a test duration of 4 days. Half of the specimens shall be unmated and the other half shall
be left mated during the test.
8 Tests and test schedule – Test group UEL 1
A minimum of 8 specimens shall be prepared for this group; then tested according to Table 1.
© IEC 2025
Table 1 – Test group UEL 1
Test Measurement to be performed
Test
Title IEC 60512 Severity or Title IEC 60512 Requirements
phase
test No. condition of test test No.
UEL General Visual 1a There shall be
1.1 examination examination no defects that
would impair
normal operation
UEL Contact 2a As specified in
1.2 resistance- the relevant
Millivolt connector
level standard
method
UEL
100 V DC Insulation 3a 500 MΩ
1.3 resistance minimum
Method A
Mated connectors
UEL Contact to contact Voltage 4a There shall be
1.4 proof no breakdown or
1 000 V DC or
flashover
1 000 V AC peak.
All signal contacts to
shield and test
panel, as applicable
1 500 V DC or
1 500 V AC peak.
Method A
Mated connectors
UEL Mechanical 9c Per 7.1 .
1.5 operations
with electrical
load
UEL Flowing 11g Per 7.2
1.6 mixed gas
corrosion test
UEL Contact 2a 20 mΩ maximum
1.7 resistance- change from
Millivolt initial
level
method
UEL Mechanical 9c Per 7.1
operations
1.8
with electrical
load
UEL Contact resistance Contact 2a 20 mΩ maximum
1.9 resistance- change from
Millivolt initial
level
method
UEL 100 V DC Insulation 3a 500 MΩ
1.10 resistance minimum
Method A
Mated connectors
REDLINE VERSION – 10 – IEC 60512-99-002:2022+AMD1:2025 CSV
© IEC 2025
Test Measurement to be performed
Test
Title IEC 60512 Severity or Title IEC 60512 Requirements
phase
test No. condition of test test No.
UEL Contact to contact Voltage 4a There shall be
1.11
proof no breakdown or
1 000 V DC or
flashover
1 000 V AC peak.
All signal contacts to
shield and test
panel, as applicable
1 500 V DC or
1 500 V AC peak.
Method A
Mated connectors
UEL General Visual 1a There shall be
1.12 examination examination no defects that
would impair
normal
operation.
However,
physical
deterioration of
the contacts may
be observed.
Such
deterioration
shall not be
cited as a failure
of this test.
© IEC 2025
Annex A
(informative)
Test voltage and current setting instructions
A.1 General
IEEE 802.3™-2018 and IEEE 802.3bt™ specify Power over Ethernet systems with a nominal
highest current per pair as shown in Table A.1 and an open circuit voltage of 55 V DC. A test
procedure for connectors for use with Type 1 and Type 2 is defined in IEC 60512-99-001.
Table A.1 – Maximum electrical circuit current per IEEE 802.3
PSE type Nominal highest current per pair Number of powered pairs
A
Type 1 0,350 2
Type 2 0,600 2
Type 3 0,6 2 or 4
Type 4 0,6 2
Type 4 0,96 4
It is possible that confusion as to how to set the required voltages and currents may arise. Given
below are a set of informative instructions as to how this may be achieved.
A.2 Rationale
The open circuit voltage requirement is stated such that during unmating under load, the stated
voltage is available to ‘drive’ arcing.
Some power sources have an ‘open circuit’ setting which is used to clamp the voltage to prevent
an over voltage condition. As no source voltage is stated for the supply in a constant voltage
mode, an interpretation of the requirements could be to set some level of source voltage (the
DC supply constant voltage setting) below, e.g., 55 V, and to set the maximum open circuit
voltage at, e.g., 55 V. But, under this interpretation, upon unmating the constant voltage setting
would not allow the voltage
...
IEC 60512-99-002 ®
Edition 2.0 2022-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Connectors for electrical and electronic equipment – Tests and measurements –
Part 99-002: Endurance test schedules – Test 99b: Test schedule for unmating
under electrical load
Connecteurs pour équipements électriques et électroniques – Essais et
mesures –
Partie 99-002: Programmes d’essais d’endurance – Essai 99b: Programme
d’essai pour le désaccouplement sous charge électrique
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IEC 60512-99-002 ®
Edition 2.0 2022-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Connectors for electrical and electronic equipment – Tests and measurements –
Part 99-002: Endurance test schedules – Test 99b: Test schedule for unmating
under electrical load
Connecteurs pour équipements électriques et électroniques – Essais et
mesures –
Partie 99-002: Programmes d’essais d’endurance – Essai 99b: Programme
d’essai pour le désaccouplement sous charge électrique
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.220.10 ISBN 978-2-8322-1068-8
– 2 – IEC 60512-99-002:2022 © IEC 2022
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 General . 6
5 Preparation of specimens . 6
6 Test circuit requirements . 6
6.1 General . 6
6.2 Voltage and current . 7
6.3 Auxiliary equipment . 8
7 Test methods . 8
7.1 Mechanical operations with electrical load . 8
7.2 Flowing mixed gas corrosion . 8
8 Tests and test schedule – Test group UEL 1 . 8
Annex A (informative) Test voltage and current setting instructions. 11
A.1 General . 11
A.2 Rationale . 11
A.3 Suggested setting instructions . 11
Bibliography . 12
Figure 1 – Test circuit details . 7
Table 1 – Test group UEL 1 . 9
Table A.1 – Maximum electrical circuit current per IEEE 802.3. 11
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CONNECTORS FOR ELECTRICAL AND ELECTRONIC EQUIPMENT –
TESTS AND MEASUREMENTS –
Part 99-002: Endurance test schedules –
Test 99b: Test schedule for unmating under electrical load
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 60512-99-002 has been prepared by subcommittee 48B: Electrical connectors, of IEC
technical committee 48: Electrical connectors and mechanical structures for electrical and
electronic equipment. It is an International Standard.
This second edition cancels and replaces the first edition published in 2019. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Test group UEL has been revised with respect to the order of the test phases, the test
severities and the requirements.
– 4 – IEC 60512-99-002:2022 © IEC 2022
The text of this International Standard is based on the following documents:
Draft Report on voting
48B/2922/FDIS 48B/2938/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 60512 series, published under the general title Connectors for
electrical and electronic equipment – Tests and measurements, can be found on the IEC
website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
CONNECTORS FOR ELECTRICAL AND ELECTRONIC EQUIPMENT –
TESTS AND MEASUREMENTS –
Part 99-002: Endurance test schedules –
Test 99b: Test schedule for unmating under electrical load
1 Scope
This part of IEC 60512 is used for the assessment of connectors within the scope of SC 48B
that are used in twisted pair communication cabling with remote power, such as
TM
ISO/IEC 11801-1 Class D, or better, balanced cabling in support of IEEE 802.3bt (Power over
Ethernet, supporting up to 90 W from the power sourcing equipment).
The object of this document is to detail a test schedule to determine the ability of sets of
connectors to withstand a minimum of 100 mechanical operations with electrical load, where an
electrical current is being passed through the connectors in accordance with IEC 60512-9-3
during the separation (unmating) step.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60512-1-1, Connectors for electronic equipment – Tests and measurements – Part 1-1:
General examination – Test 1a: Visual examination
IEC 60512-2-1, Connectors for electronic equipment – Tests and measurements – Part 2-1:
Electrical continuity and contact resistance tests – Test 2a: Contact resistance – Millivolt level
method
IEC 60512-3-1, Connectors for electronic equipment – Tests and measurements – Part 3-1:
Insulation tests – Test 3a: Insulation resistance
IEC 60512-4-1, Connectors for electronic equipment – Tests and measurements – Part 4-1:
Voltage stress tests – Test 4a: Voltage proof
IEC 60512-9-3, Connectors for electronic equipment – Tests and measurements – Part 9‑3:
Endurance tests – Test 9c: Mechanical operation (engaging and separating) with electrical load
IEC 60512-11-7, Connectors for electronic equipment – Tests and measurements – Part 11-7:
Climatic tests – Test 11g: Flowing mixed gas corrosion test
IEEE Std 802.3™-2018, IEEE Standard for Ethernet
IEEE Std 802.3bt™-2018, IEEE Standard for Ethernet. Amendment 2: Physical Layer and
Management Parameters for Power over Ethernet over 4 pairs
– 6 – IEC 60512-99-002:2022 © IEC 2022
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 General
Although separating (unmating) connectors under the scope of this document, while used for
remote powering, is a misuse of the connector, it may occur in practice.
This test schedule is suitable for verification of separating (unmating) of connectors under load
TM
conditions representative for Power over Ethernet Type 4 as specified per IEEE 802.3bt . An
application-specific current and the associated open circuit voltage are specified, that
correspond with the current and voltage of the supported application.
5 Preparation of specimens
Each specimen shall consist of a mated set of connectors with its terminations. Specimens shall
conform to the relevant IEC connector standard. Each free and each fixed connector shall be
terminated with 3 m (max.) of the maximum conductor size cable for which it is intended to be
terminated, according to the appropriate IEC standard(s). Fixed connectors may alternatively
be terminated using a printed circuit board which shall not influence the test results.
For each specimen, all circuits (mated contacts) shall be wired in parallel as given in
IEC 60512-9-3, and all circuits shall be tested.
6 Test circuit requirements
6.1 General
The values for the circuit components and the details of the test circuit, referenced in
IEC 60512-9-3, shall be as shown in Figure 1.
Key
W Cables in accordance with Clause 5
Q1 Specimen under test
L1 Inductor, L = 100 μH
R1 Variable resistor (e.g. R = 25 Ω to 300 Ω)
C1 Capacitor, C = 5 µF
E1 Voltage source
S1 Switch
Figure 1 – Test circuit details
NOTE 1 Only one circuit of the specimen under test, as referenced in IEC 60512-9-3, is shown for clarity. Items W,
L1, R1 and C1 are replicated for each circuit of the specimen. Items E1 and S1 may be single or multiple. All circuits
of the specimen are wired in parallel with appropriate duplication of circuit components, and all circuits of the
specimen are operated simultaneously.
NOTE 2 The variable resistor is used to adjust the current to the specified value.
6.2 Voltage and current
The variable resistor(s) shall be set so that the electrical current in each circuit (mated contacts)
+0,05
of the specimen is 2,0 A. During the separation (unmating) step, the open circuit voltage,
+1
in all circuits, shall be 55 V DC. During the engagement (mating) step, the open circuit
voltage, in all circuits, shall be 0 V DC by operating the switch, S1, before each connector
engagement (mating).
IEEE 802.3™-2018 and IEEE 802.3bt™ specify Power over Ethernet systems with a nominal
highest current per pair depending on the type of power sourcing equipment (PSE) and the
number of powered pairs, and with an open circuit voltage of 55 V DC.
For PSE Type 4, the nominal highest current per pair is 0,96 A when all four pairs are powered,
giving a total source current of 1,92 A. The test current per contact has been set to 2,0 A to
represent the highly probable case that one contact is separated after all others, causing this
contact to carry the full current just before disconnecting.
As the resistive load is likely to rise due to heating and due to wear of contacts in the connector
under test, care should be placed in keeping the value of test current within the specified
tolerance range, e.g. by means of a suitable feedback control circuit acting on the value of the
variable resistor. See Annex A (informative) for further guidance.
– 8 – IEC 60512-99-002:2022 © IEC 2022
6.3 Auxiliary equipment
Switches may be used to reverse polarity. However, use of such switches shall not influence
the test parameters.
7 Test methods
7.1 Mechanical operations with electrical load
An electrical load, current and open circuit voltage, as detailed in 6.2, shall be applied to each
specimen.
For the purpose of this test, one connector shall be fixed and the other disengaged at a speed
of 150 mm/s ± 10 mm/s.
One engagement and one separation constitute one cycle.
25 cycles at one polarity of the DC source shall be performed. The polarity of the DC source
shall then be reversed and 25 further cycles at the other polarity shall be performed (50 cycles
total). The electrical current shall be applied during the separation step only.
7.2 Flowing mixed gas corrosion
The flowing mixed gas corrosion test shall be performed according to IEC 60512-11-7, method
1, with a test duration of 4 days. Half of the specimens shall be unmated and the other half shall
be left mated during the test.
8 Tests and test schedule – Test group UEL 1
A minimum of 8 specimens shall be prepared for this group; then tested according to Table 1.
Table 1 – Test group UEL 1
Test Measurement to be performed
Test
Title IEC 60512 Severity or Title IEC 60512 Requirements
phase
test No. condition of test test No.
UEL General Visual 1a There shall be
1.1 examination examination no defects that
would impair
normal operation
UEL Contact 2a As specified in
1.2 resistance- the relevant
Millivolt connector
level standard
method
UEL
100 V DC Insulation 3a 500 MΩ
1.3 resistance minimum
Method A
Mated connectors
UEL Contact to contact Voltage 4a There shall be
1.4 proof no breakdown or
1 000 V DC or
flashover
1 000 V AC peak.
All signal contacts to
shield and test
panel, as applicable
1 500 V DC or
1 500 V AC peak.
Method A
Mated connectors
UEL Mechanical 9c Per 7.1 .
1.5 operations
with electrical
load
UEL Flowing 11g Per 7.2
1.6 mixed gas
corrosion test
UEL Contact 2a 20 mΩ maximum
1.7 resistance- change from
Millivolt initial
level
method
UEL Mechanical 9c Per 7.1
operations
1.8
with electrical
load
UEL Contact resistance Contact 2a 20 mΩ maximum
1.9 resistance- change from
Millivolt initial
level
method
UEL 100 V DC Insulation 3a 500 MΩ
1.10 resistance minimum
Method A
Mated connectors
– 10 – IEC 60512-99-002:2022 © IEC 2022
Test Measurement to be performed
Test
Title IEC 60512 Severity or Title IEC 60512 Requirements
phase
test No. condition of test test No.
UEL Contact to contact Voltage 4a There shall be
1.11
proof no breakdown or
1 000 V DC or
flashover
1 000 V AC peak.
All signal contacts to
shield and test
panel, as applicable
1 500 V DC or
1 500 V AC peak.
Method A
Mated connectors
UEL General Visual 1a There shall be
1.12 examination examination no defects that
would impair
normal
operation.
However,
physical
deterioration of
the contacts may
be observed.
Such
deterioration
shall not be
cited as a failure
of this test.
Annex A
(informative)
Test voltage and current setting instructions
A.1 General
IEEE 802.3™-2018 and IEEE 802.3bt™ specify Power over Ethernet systems with a nominal
highest current per pair as shown in Table A.1 and an open circuit voltage of 55 V DC. A test
procedure for connectors for use with Type 1 and Type 2 is defined in IEC 60512-99-001.
Table A.1 – Maximum electrical circuit current per IEEE 802.3
PSE type Nominal highest current per pair Number of powered pairs
A
Type 1 0,350 2
Type 2 0,600 2
Type 3 0,6 2 or 4
Type 4 0,6 2
Type 4 0,96 4
It is possible that confusion as to how to set the required voltages and currents may arise. Given
below are a set of informative instructions as to how this may be achieved.
A.2 Rationale
The open circuit voltage requirement is stated such that during unmating under load, the stated
voltage is available to ‘drive’ arcing.
Some power sources have an ‘open circuit’ setting which is used to clamp the voltage to prevent
an over voltage condition. As no source voltage is stated for the supply in a constant voltage
mode, an interpretation of the requirements could be to set some level of source voltage (the
DC supply constant voltage setting) below, e.g., 55 V, and to set the maximum open circuit
voltage at, e.g., 55 V. But, under this interpretation, upon unmating the constant voltage setting
would not allow the voltage to reach the intended open circuit level.
A.3 Suggested
...
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