SIST EN 61076-4-103:2002

SLOVENSKI STANDARD
01-september-2002
Connectors with assessed quality, for use in d.c., low frequency analogue and
digital high-speed data applications - Part 4-103: Printed board connectors with
assessed quality- Detail specification for two-part connectors with shielding and a
basic grid of 2,5 mm (IEC 61076-4-103:1999
Connectors for use in d.c. low-frequency analogue and digital high speed data
applications -- Part 4-103: Printed board connectors with assessed quality - Detail
specification for two-part connectors with shielding and a basic grid of 2,5 mm
Steckverbindungen für Gleichspannungs- und Niederfrequenzanwendungen sowie
digitale Anwendungen mit hoher Übertragungsrate -- Teil 4-103: Steckverbinder für
gedruckte Schaltungen mit bewerteter Qualität - Bauartspezifikation für geschirmte
indirekte Steckverbinder, Raster 2,5 mm
Connecteurs pour applications analogiques en courant continu et à basse fréquence et
pour applications numériques utilisant des débits élevés pour le transfert des données --
Partie 4-103: Connecteurs pour cartes imprimées sous assurance de la qualité -
Spécification particulière pour connecteurs en deux parties avec blindage au pas de
base de 2,5 mm
Ta slovenski standard je istoveten z: EN 61076-4-103:1999
ICS:
31.220.10 9WLþLLQYWLþQLFHNRQHNWRUML Plug-and-socket devices.
Connectors
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

NORME
CEI
INTERNATIONALE
IEC
61076-4-103
INTERNATIONAL
QC 480301XX0004
STANDARD
Première édition
First edition
1999-02
Connecteurs pour applications analogiques
en courant continu et à basse fréquence et pour
applications numériques utilisant des débits élevés
pour le transfert des données –
Partie 4-103:
Connecteurs pour cartes imprimées sous assurance
de la qualité –
Spécification particulière pour connecteurs
en deux parties avec blindage au pas de base
de 2,5 mm
Connectors for use in d.c. low-frequency analogue
and digital high speed data applications –
Part 4-103:
Printed board connectors with assessed quality –
Detail specification for two-part connectors
with shielding and a basic grid of 2,5 mm
 IEC 1999 Droits de reproduction réservés  Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in
utilisée sous quelque forme que ce soit et par aucun any form or by any means, electronic or mechanical,
procédé, électronique ou mécanique, y compris la photo- including photocopying and microfilm, without permission in
copie et les microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http://www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale
PRICE CODE XB
International Electrotechnical Commission
Pour prix, voir catalogue en vigueur
For price, see current catalogue

61076-4-103 © IEC:1999 – 3 –
CONTENTS
Page
FOREWORD . 11
Clause
1 General data. 15
1.1 Recommended method of mounting . 15
1.1.1 Number of contacts and contact cavities. 15
1.2 Ratings and characteristics . 17
1.3 Normative references. 21
1.4 Marking. 23
1.5 IEC type designation . 23
1.6 Ordering information. 25
2 Technical data. 27
2.1 Definitions. 27
2.1.1 Mechanical features. 27
2.1.2 Contacts and terminations . 27
2.1.3 Engagement sequence. 27
2.1.4 Mechanical coding. 29
2.2 Survey of styles and variants. 29
2.2.1 Styles of connectors . 29
2.2.2 Survey of termination variants . 31
2.2.3 Survey of cable diameters . 31
2.3 Information on application . 33
2.3.1 Complete connectors (pairs). 33
2.3.2 Fixed board connectors . 35
2.3.3 Free cable connectors . 37
2.3.4 Coding device. 39
2.3.5 Shielding and grounding . 41
2.4 Survey of contact arrangements . 41
3 Dimensional information. 43
3.1 General. 43
3.2 Isometric view and common features. 45
3.2.1 Common features. 45
3.2.2 Reference system. 47
3.2.3 Height dimensions. 47
3.2.4 Width dimensions. 49
3.2.5 Depth dimensions. 49
3.3 Mating information. 51
3.3.1 Engaging direction. 51
3.3.2 Perpendicular to the engaging direction . 51
3.3.3 Inclination. 53
3.4 Fixed board connectors. 57
3.4.1 Dimensions of connector shrouds . 57
3.4.2 Dimensions of contacts . 63
3.4.3 Terminations. 63

61076-4-103 © IEC:1999 – 5 –
Clause Page
3.5 Free cable connectors. 67
3.5.1 Dimensions of cable connectors . 67
3.5.2 Dimensions of contacts . 73
3.5.3 Terminations. 73
3.6 Accessories. 77
3.6.1 Default coding configuration . 77
3.7 Mounting information for fixed board connectors. 79
3.8 Gauges. 79
3.8.1 Sizing gauges and retention force gauges. 81
3.8.2 Test gauge for first contact point . 83
3.8.3 Test gauge for static load . 85
4 Characteristics. 85
4.1 Climatic category. 85
4.2 Electrical characteristics. 85
4.2.1 Creepage and clearance distances . 85
4.2.2 Voltage proof. 87
4.2.3 Current-carrying capacity. 87
4.2.4 Contact resistance. 89
4.2.5 Insulation resistance. 89
4.3 Mechanical characteristics. 91
4.3.1 Mechanical operation. 91
4.3.2 Engaging and separating forces . 91
4.3.3 Contact retention in insert. 91
4.3.4 Static load, transverse. 93
4.3.5 Gauge retention force. 93
4.3.6 Vibration (sinusoidal). 93
4.3.7 Shock. 95
4.3.8 Polarizing method. 95
4.3.9 Robustness and effectiveness of coding devices . 95
4.3.10 Insert retention in housing (axial). 97
4.3.11 Cable clamp resistance to cable rotation. 97
4.3.12 Effectiveness of connector coupling devices . 97
4.3.13 Shielding contact spring holding force. 97
4.4 Electromagnetic compatibility (EMC) . 99
4.4.1 Shielding effectiveness of connectors . 99
4.4.2 Electrostatic discharge (ESD) . 99
5 Test schedule. 99
5.1 General. 99
5.1.1 Arrangement for contact resistance measurements. 101
5.1.2 Arrangement for dynamic stress tests. 103
5.1.3 Arrangement for testing static load, transverse . 103
5.1.4 Arrangement for voltage proof and polarization voltage . 105
5.1.5 Arrangement for flammability test . 105
5.1.6 Arrangement for shielding effectiveness test. 107
5.1.7 Arrangement for electrostatic discharge test . 107

61076-4-103 © IEC:1999 – 7 –
Clause Page
5.2 Test schedule tables . 109
5.2.1 Group P – Preliminary . 109
5.2.2 Group A – Dynamic/climatic. 111
5.2.3 Group B – Mechanical endurance . 115
5.2.4 Group C – Moisture . 117
5.2.5 Group D – Electrical load. 119
5.2.6 Group E – Mechanical resistivity. 121
5.2.7 Group F – Chemical resistivity . 123
5.2.8 Group G – Connections . 123
6 Quality assessment procedures. 123
6.1 Qualification approval testing . 123
6.1.1 Method 1. 123
6.1.2 Method 2. 125
6.2 Quality conformance inspection. 125
6.2.1 Lot-by-lot tests. 125
6.2.2 Periodic tests. 125
6.3 Delayed delivery, re-inspection. 127
Tables
1 Number of contacts and contact cavities for free cable connectors. 15
2 Number of contacts and contact cavities for fixed board connectors. 17
3 Survey of free cable connector styles . 29
4 Termination variants. 31
5 Cable diameters . 31
6 Coordination dimensions and common features in metric equipment practice. 45
7 Crimped terminations . 73
8 IDC terminations . 75
9 Climatic category. 85
10 Minimum creepage and clearance distances for different contact arrangements. 87
11 Voltage proof for different contact arrangements . 87
12 Current-carrying capacity for different contact arrangements. 87
13 Insulation resistance . 89
14 Number of mechanical operations . 91
15 Engaging and separating forces . 91
16 Contact retention force in insert for different types of terminations . 91
17 Vibration . 9 3
18 Shock . 95
19 Insert retention forces in housing. 97
20 Number of specimens for inspection and test sequence. 101
21 Group P – Preliminary testing sequence . 109
22 Group A – Dynamic/climatic testing sequence. 111
23 Group B – Mechanical endurance testing sequence . 115
24 Group C – Moisture testing sequence . 117
25 Group D – Electrical load testing sequence. 119
26 Group E – Mechanical resistivity testing sequence. 121
27 Group F – Chemical resistivity testing sequence . 123
28 Number of specimens and permitted defectives . 123
29 Assessment levels and AQL values . 125
30 Periodic tests, number of specimens and permitted defectives. 127
31 Re-inspection of delayed delivery . 127

61076-4-103 © IEC:1999 – 9 –
Page
Figures
1 Three recommended applications for cable-to-board connectors. 19
2 Survey of fixed board connector styles. 31
3 Contact designation for different applications. 35
4 Coordination dimensions in metric equipment practice . 45
5 Height dimensions, modular pitch of 25 mm. 47
6 Width dimensions, modular pitches . 49
7 Depth dimensions . 49
8 Contact range . 51
9 Allowed misalignment in transverse and longitudinal axes. 53
10 Allowed inclination during insertion . 53
11 Allowed inclination from transverse and longitudinal axes . 55
12 Overall dimensions of fixed shroud style P and style Q . 57
13 Overall dimensions of fixed shroud style R and style T. 59
14 Detailed dimensions of fixed shrouds. 61
15 Dimensions of male contacts for fixed connector shroud. 63
16 Straight press-in terminations . 63
17 Straight terminations with rear plug-up contacts. 65
18 Detailed dimensions of styles A, B and C. 67
19 Overall dimensions of style A, straight short housing . 69
20 Dimensions of style B, straight long housing . 71
21 Dimensions of style C, angled 35° upwards . 71
22 Dimensions of guiding apertures in free board connector . 73
23 Depth dimensions on female contact . 73
24 Angled press-in terminations . 75
25 Configuration of default code setting. 77
26 Hole pattern on backplane for styles P and Q . 79
27 Sizing and retention force gauges for female contacts . 81
28 Retention force gauge for grounding spring contacts. 83
29 First contact point gauge for female contacts. 83
30 Test gauge for static load on locking device. 85
31 Current-carrying capacity: derating curves for different contact arrangements . 89
32 Connection points for contact resistance measurement. 101
33 Fixture for dynamic stress tests . 103
34 Arrangement for static load, transverse test. 103
35 Wiring arrangement for voltage proof and polarization voltage . 105
36 Arrangement for flammability test . 105
37 Arrangement for shielding effectiveness test. 107
38 Arrangement for electrostatic discharge test . 107

61076-4-103 © IEC:1999 – 11 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_________
CONNECTORS FOR USE IN DC
LOW-FREQUENCY ANALOGUE AND
DIGITAL HIGH SPEED DATA APPLICATIONS –
Part 4-103: Printed board connectors with assessed quality –
Detail specification for two-part connectors with shielding
and a basic grid of 2,5 mm
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical reports or guides and they are accepted by the National Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61076-4-103 has been prepared by subcommittee 48B: Connectors,
of IEC technical committee 48: Electromechanical components and mechanical structures for
electronic equipment.
The text of this standard is based on the following documents:
FDIS Report on voting
48B/737/FDIS 48B/750/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
Future standards in the series will carry the new general title as cited above. Titles of existing
standards in this series will be updated when a new edition is prepared.
The QC number that appears on the front cover of this publication is the specification number
in the IEC Quality Assessment System for Electronic Components (IECQ).

61076-4-103 © IEC:1999 – 13 –
CONNECTORS FOR USE IN DC
LOW-FREQUENCY ANALOGUE AND
DIGITAL HIGH SPEED DATA APPLICATIONS –
Part 4-103: Printed board connectors with assessed quality –
Detail specification for two-part connectors with shielding
and a basic grid of 2,5 mm
International Electrotechnical Commission IEC 61076-4-103
QC 480301XX0004
IEC SC 48B – Connectors
Electronic components of assessed quality in accordance with: Blank detail specification:
GENERIC SPECIFICATION IEC 61076-1, Issue 1, 1995 IEC 61076-4-001, Issue 1, 1996
Cable-to-board connectors, shielded,
for printed boards and backplanes,
grid of 2,5 mm, in accordance with
IEC 60917.
Modular, five-row connector, with
high performance shielding, locking
and coding features.
Fixed board connectors
25 mm to 250 mm high,
free cable connectors
25 mm to 100 mm high.
Performance levels (PL): 1, 2
Assessment level: G
IEC  1 882/98
Information on the availability of components qualified to this detail specification is given in the qualified products
list.
61076-4-103 © IEC:1999 – 15 –
1 General data
1.1 Recommended method of mounting
The free cable connector shall be connected to a round cable.
The shielding braid of the cable shall be connected to the conductive shell of the housing, and
the insulation of the cable shall be retained by a strain relief device.
The signal wires shall be connected either directly to the female contacts by crimped or
insulation displacement connections (IDC), or to an internal printed circuit board by means of a
transition device.
The cable-to-board connectors are recommended for the use in three different applications:
Application a, rear plug-up connection;
Application b, connection to backplane;
Application c, connection through front panel.
See figure 1 for location of the above-mentioned reference letters.
Depending on the application the fixed board connectors shall be attached to the backplane or
to the front panel through the press-in connections of their shielding frames.
Application a: for rear plug-up connections, the empty shroud of the fixed board
connector accommodates the rear plug-up terminations of the fixed connector, which is
mounted on the frontside of the backplane (for example a fixed board connector according
to IEC 61076-4-100).
Application b: for backplane connections, the fixed board connector shall be equipped with
male contacts, which are pressed into the backplane, together with the press-in terminations of
its shielding frames.
Application c: for front panel connections, the fixed board connector shall be equipped with
male contacts and rear plug-up terminations, which connect to a free connector on the printed
board (for example a free board connector according to IEC 61076-4-100).
1.1.1 Number of contacts and contact cavities
Table 1 – Number of contacts and contact cavities for free cable connectors
Styles Shape of Connection ½ SU 1 SU 2 SU 4 SU
(see 2.2.1) housing
A Straight, short IDC or crimp 20 45 90 180
B Straight, long Angled press-in – 35 70 140
IDC or crimp – 45 90 180
C 35° angled IDC or crimp – 45 90 180

61076-4-103 © IEC:1999 – 17 –
Table 2 – Number of contacts and contact cavities for fixed board connectors
Styles (see 2.2.1) 1 SU 2 SU 4 SU 6 SU 8 SU 9 SU 10 SU
P and Q 45 90 180 270 360 405 450
R and T 40 80 160 240 320 360 400
1.2 Ratings and characteristics
Rated voltage: contact/contact 500 V r.m.s.
Current rating: 1 A at 70 °C (all signal contacts loaded)
Insulation resistance: 5 GΩ min.
Climatic category: PL 1: 40/100/56
PL 2: 40/100/21
Shielding effectiveness: initial 70 dB min. average value
Electrostatic discharge: induced voltage 250 mV maximum by 8 kV contact discharge
Printed board: plated-through hole diameter 0,94 mm to 1,09 mm
Backplane thickness:
– for rear plug-up applications 3,0 mm to 5,0 mm
– other than rear plug-up applications 1,4 mm to 5,6 mm

61076-4-103 © IEC:1999 – 19 –
Figure 1a - Rear plug-up connection
Figure 1b - Connection to backplane
Figure 1c - Connection through front panel
IEC  1 883/98
Figure 1 – Three recommended applications for cable-to-board connectors

61076-4-103 © IEC:1999 – 21 –
1.3 Normative references
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 61076. At the time of publication, the editions indicated
were valid. All normative documents are subject to revision, and parties to agreements based
on this part of IEC 61076, are encouraged to investigate the possibility of applying the most
recent editions of the normative documents indicated below. Members of IEC and ISO maintain
registers of currently valid International Standards.
IEC 60068-1:1988, Environmental testing – Part 1: General and guidance
IEC 60352-5:1995, Solderless connections – Part 5: Solderless press-in connections – General
requirements, test methods and practical guidance
IEC 60410:1973, Sampling plans and procedures for inspection by attributes
IEC 60512:—, Electromechanical components for electronic equipment – Basic testing
procedures and measuring methods
IEC 60512-2:1985, Electromechanical components for electronic equipment – Basic testing
procedures and measuring methods – Part 2: General examination, electrical continuity and
contact resistance tests, insulation tests and voltage stress tests
IEC 60512-3:1976, Electromechanical components for electronic equipment – Basic testing
procedures and measuring methods – Part 3: Current carrying capacity tests
IEC 60512-4:1976, Electromechanical components for electronic equipment – Basic testing
procedures and measuring methods – Part 4: Dynamic stress tests
IEC 60512-5:1992, Electromechanical components for electronic equipment – Basic testing
procedures and measuring methods – Part 5: Impact tests (free components), static load tests
(fixed components), endurance tests and overload tests
IEC 60512-7:1993, Electromechanical components for electronic equipment – Basic testing
procedures and measuring methods – Part 7: Mechanical operating tests and sealing tests
IEC 60512-8:1993, Electromechanical components for electronic equipment – Basic testing
procedures and measuring methods – Part 8: Connector tests (mechanical) and mechanical
tests on contacts and terminations
IEC 60512-9:1992, Electromechanical components for electronic equipment – Basic testing
procedures and measuring methods – Part 9: Miscellaneous tests
IEC 60512-23-3:—, Electromechanical components for electronic equipment – Basic testing pro-
cedures and measuring methods – Part 23: Electromagnetic compatibility – Section 3: Test 23c:
1)
Shielding effectiveness, from 10 kHz to 1 000 kHz, on connectors with cables affixed
IEC 60917:1988, Modular order for the development of mechanical structures for electronic
equipment practices
IEC 60917-2-2:1994, Modular order for the development of mechanical structures for electronic
equipment practices – Part 2: Sectional specification – Interface coordination dimensions for
the 25 mm equipment practice – Section 2: Detail specification – Dimensions for subracks,
chassis, backplanes, front panels and plug-in units
________
1)
To be published.
61076-4-103 © IEC:1999 – 23 –
IEC 61000-4-2:1995, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement
techniques – Section 2: Electrostatic discharge immunity test – Basic EMC publication
IEC 61076-1:1995, Connectors with assessed quality, for use in d.c., low frequency analogue
and in digital high speed data applications – Part 1: Generic specification
IEC 61076-4:1995, Connectors with assessed quality, for use in d.c., low frequency analogue
and in digital high speed data applications – Part 4: Sectional specification – Printed board
connectors
IEC 61076-4-100:1994, Connectors with assessed quality, for use in d.c., and low frequency
analogue applications and in digital applications with high speed data – Part 4: Sectional
specification – Printed board connectors – Section 100: Detail specification for two-part
connectors having a basic grid of 2,5 mm, for printed boards and backplanes
ISO 468:1982, Surface roughness – Parameters, their values and general rules for specifying
requirements
1.4 Marking
The marking of the connector and the package shall be in accordance with 2.6 of IEC 61076-4.
1.5 IEC type designation
See 2.1 for definitions and 2.2 for designation of styles and variants.
The designation shall be derived in accordance with 2.5 of IEC 61076-4.
Example for free cable connector:
A straight 1 SU free cable connector with cable adapter for cables Ø 10 mm, fully loaded with
palladium and gold-flash plated contacts in all five rows with 90° angled press-in terminations
for internal printed board, meeting performance level 2 and assessment level G, is designated
as follows:
IEC 61076-4-103 – B035F510 – L140202G
Example for fixed connector:
A 10 SU fixed board connector, fully loaded in all five rows with signal contacts level 1 and 12 mm
rear plug-up spills, palladium and gold-flash plated, and with silver alloy plated shielding
contacts, meeting performance level 1 and assessment level G, is designated as follows:
IEC 61076-4-103 – Q450M511 – U100231G
Example for single contacts:
A single female contact, with crimp termination, palladium and gold-flash plated, meeting
performance level 2 and assessment level G, is designated as follows:
IEC 61076-4-103 – S001F000 – C100202G

61076-4-103 © IEC:1999 – 25 –
IEC 61076-4-103 L N N N L N N N L N N N N N N L NOTE – L stands for letter,
– –
N stands for digit.
Reference to this
specification
Assessment level
Connector style
G Level G
(see 2.2.1)
Cable connector straight
Performance level
short A
long B
1 Performance level 1
Cable connector angled 35° C
2 Performance level 2
Plug-up shroud P
Loaded shroud Q
Plug-up shroud with ½ SU R Contact finish of
compartments
shielding contacts
Single contact S
0 Not applicable
Loaded shroud with ½ SU T
1 Unplated
compartments
2 Silver alloy
Number of contact cavities
Contact finish of signal contact
(depending on connector style:
see 1.1.1)
0 Not applicable
1 Gold alloy
Single contact 001 – –
2 Palladium alloy with gold flash
1/2 SU 020 – –
1 SU 045 035 040
2 SU 090 070 080
Cable diameter (see 2.2.3)
4 SU 180 140 160
00 Blind / not applicable
6 SU 270 – 240
9 SU 405 – 360
XX See table in 2.2.3
10 SU 450 – 400
Type of contact
Type of termination        Variant
(see 2.2.2)
Female F
Male M
C1 Crimp small
Coding device K
C2 average
I1 Insulation displacement small
Loaded contact rows (see 2.4)
I2 average
L1 Press-in angled 3 mm
Empty body 0
/ not applicable P1 Press-in straight 4,5 mm
a + c + e 1 P2 6 mm
b + d 2
U1 Rear plug-up 12 mm
a + b + c + d + e 5
Z0 Not applicable
Pattern of loaded contacts
Pattern of contact levels (see 2.4)
(see 2.4)
Empty body 0 0 Empty body
/ not applicable
/ not applicable
Fully loaded 1
1 All contacts level 1
All even numbered contacts 3
2 Level 2 at corner contacts, others level 1
Chess pattern even numbered in row a 5
1.6 Ordering information
For ordering connectors according to this detail specification, the IEC type designation
described in 1.5 shall be used.

61076-4-103 © IEC:1999 – 27 –
2 Technical data
2.1 Definitions
For the purpose of this part the following definitions apply:
2.1.1 Mechanical features
internal printed board
printed board which is mounted inside the free cable connector housing, connected to the free
connector insert by means of angled press-in terminations
location pegs
posts, protruding from the connector housing, fitting into corresponding holes in the printed
board or backplane, preventing a wrong assembly and giving an accurate position
locking device
device which retains the free cable connector in its mated state and withstands the specified
static load
locking latches
elastic levers which snap under the noses of the free cable connector housing on full insertion
system unit (SU)
modular pitch of 25 mm, which is the basis for the design of all mechanical features
2.1.2 Contacts and terminations
contact range
the minimum to maximum distance between the reference planes of the fixed and free board
connectors, within which the specified contact resistance is met
chess pattern
contact arrangement where the loaded and the unloaded positions alternate in rows and
columns, like the fields on a chess-board
chess pattern, odd in a
chess pattern having loaded contacts on odd positions in row a
rear plug-up contact
termination post, usually being pressed-in into the backplane and emerging on the rear side as
a male contact, to be connected to a free board connector
press-in shoulders
flanges on both sides of the male contact, supporting the mechanical forces to press the
contact into the backplane
2.1.3 Engagement sequence
contact level
group of contacts which engage/separate simultaneously, within the limits required by a reliable
engaging sequence
engaging sequence
distinct order in the engaging/separating process of contacts belonging to different contact
levels
first possible contact point
depth dimension of the first point on the female contact, which can possibly be touched by the
incoming male contact
first reliable contact point
depth dimension of the point on the female contact, from where the specified contact
resistance with the incoming male contact is met

61076-4-103 © IEC:1999 – 29 –
2.1.4 Mechanical coding
coding devices
accessories allowing the user to make specific pairs of connectors by providing them with
matching coding devices
Only connector pairs equipped with matching coding devices are intermateable, pairs with
interfering coding devices are blocked off during insertion, preventing all electrical contact.
default code
solid, pre-set coding configuration in the free-cable and fixed-board connectors, making them a
matching pair, and protecting them in the future from mating with specific code settings
2.2 Survey of styles and variants
2.2.1 Styles of connectors
Free cable connectors
Table 3 – Survey of free cable connector styles
Style ½ SU 1 SU 2 SU 4 SU
A
Straight short,
for crimp or
IDC
terminations
B
Straight long,
for crimp or
IDC
terminations
and for angled
press-in
connection of
internal printed
board
C
Angled 35°
upwards,
for crimp or
IDC
terminations
61076-4-103 © IEC:1999 – 31 –
Fixed board connector shrouds
IEC  1 884/98
Figure 2 – Survey of fixed board connector styles
2.2.2 Survey of termination variants
Table 4 – Termination variants
Variant Length or wire gauge
Basic type of termination
(see 3.4.3 and 3.5.3)
2 2
C C1 Stranded wire 0,09 mm to 0,14 mm
Crimp connection,
according to IEC 60352-2
2 2
Stranded wire 0,22 mm to 0,35 mm
C2
I I1 Solid wire: Ø 0,25 mm to 0,40 mm
2 2
7-stranded wire: 0,09 mm to 0,14 mm
Insulation displacement connection
according to IEC 60352-3
I2 Solid wire: Ø 0,40 mm to 0,63 mm
2 2
7-stranded wire: 0,22 mm to 0,35 mm
L 3 mm
L1
90° angled compliant press-in connection
for plated-through hole Ø 1,
according to IEC 60352-5
P P1 4,5 mm
Straight compliant press-in connection for
plated-through hole Ø 1,
according to IEC 60352-5
P2 6 mm
U Straight, with rear plug-up contact area 12 mm
U1
2.2.3 Survey of cable diameters
Table 5 – Cable diameters
Style of housing Designation in 1.5 Nominal cable Tolerance range of
( = Ø × 4 ) diameter cable Ø
mm mm
All 00 Blind –
All 20 5
24 6
28 7 +0,4
32 8 –0,8
36 9
40 10
1 SU, 2 SU, 4 SU 44 11 +0,5
48 12 –1,0
52 13
61076-4-103 © IEC:1999 – 33 –
2.3 Information on application
2.3.1 Complete connectors (pairs)
Description
The connector family has a basic grid of 2,5 mm and a mounting pitch of 25 mm (System
Unit = SU).
It consists of a fixed connector with a modular shielded shroud, where a plurality of shielded
free cable connectors may be plugged-in.
The fixed connector shroud has up to 10 slots of 25 mm long.
The free connector housings may have up to four inserts of 25 mm long, they may be stacked
end to end, and fit in all slots of the modular shroud.
The smallest free connector housings, with only half an insert (12,5 mm), are used in pairs,
and together fit in one slot of the modular shroud.
Electrically, the shielding braid of the round cables is connected to the housing shells of the
free connectors.
These shells make contact with the shielding frames on four sides in the slots of the modular
shroud. The shielding frames of the modular shroud are pressed-in the backplane or the front
panel of the equipment practice.
Mechanically, the round cables are clamped to the housing shells of the free connectors.
These housings snap under the locking latches of the modular shroud. The locking latches are
part of the shielding frames of the modular shroud, and are mechanically fixed to the backplane
or the front panel by means of the press-in connections.
The free connectors may only be released from the modular shroud with an extraction tool.
Contact designation
The three recommended methods of mounting (see 1.1) allow opposite mating directions in
relation to the equipment, therefore the designation of the contact rows shall be inverted in the
rear plug-up shroud.
61076-4-103 © IEC:1999 – 35 –
The contact rows and columns shall be designated according to the following figure:
IEC  1 885/98
Figure 3 – Contact designation for different applications
2.3.2 Fixed board connectors
Polarization
The location peg, near contact a1 at the b
...