SIST EN 60947-4-3:2000/A1:2007

SLOVENSKI STANDARD
SIST EN 60947-4-3:2000/A1:2007
01-september-2007
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Low-voltage switchgear and controlgear -- Part 4-3: Contactors and motor-starters - AC
semiconductor controllers and contactors for non-motor loads (IEC 60947-4-
3:1999/A1:2006)
Niederspannungsschaltgeräte -- Teil 4-3: Schütze und Motorstarter - Halbleiter-
Steuergeräte und -Schütze für nichtmotorische Lasten für Wechselspannung (IEC 60947
-4-3:1999/A1:2006)
Appareillage a basse tension -- Partie 4-3: Contacteurs et démarreurs de moteurs -
Gradateurs et contacteurs a semiconducteurs pour charges, autres que des moteurs, a
courant alternatif (IEC 60947-4-3:1999/A1:2006)
Ta slovenski standard je istoveten z: EN 60947-4-3:2000/A1:2006
ICS:
29.130.20 Nizkonapetostne stikalne in Low voltage switchgear and
krmilne naprave controlgear
SIST EN 60947-4-3:2000/A1:2007 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

EUROPEAN STANDARD
EN 60947-4-3/A1

NORME EUROPÉENNE
December 2006
EUROPÄISCHE NORM

ICS 29.130.20


English version


Low-voltage switchgear and controlgear
Part 4-3: Contactors and motor-starters -
AC semiconductor controllers and contactors for non-motor loads
(IEC 60947-4-3:1999/A1:2006)


Appareillage à basse tension  Niederspannungsschaltgeräte
Partie 4-3: Contacteurs Teil 4-3: Schütze und Motorstarter -
et démarreurs de moteurs - Halbleiter-Steuergeräte und -Schütze
Gradateurs et contacteurs für nichtmotorische Lasten
à semiconducteurs pour charges, für Wechselspannung
autres que des moteurs, (IEC 60947-4-3:1999/A1:2006)
à courant alternatif
(CEI 60947-4-3:1999/A1:2006)




This amendment A1 modifies the European Standard EN 60947-4-3:2000; it was approved by CENELEC on
2006-11-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this amendment the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This amendment exists in three official versions (English, French, German). A version in any other language
made by translation under the responsibility of a CENELEC member into its own language and notified to the
Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels


© 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60947-4-3:2000/A1:2006 E

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EN 60947-4-3:2000/A1:2006 - 2 -
Foreword
The text of document 17B/1486/FDIS, future amendment 1 to IEC 60947-4-3:1999, prepared by SC 17B,
Low-voltage switchgear and controlgear, of IEC TC 17, Switchgear and controlgear, was submitted to the
IEC-CENELEC parallel vote and was approved by CENELEC as amendment A1 to EN 60947-4-3:2000
on 2006-11-01.
The following dates were fixed:
– latest date by which the amendment has to be
implemented at national level by publication of
an identical national standard or by endorsement (dop) 2007-08-01
– latest date by which the national standards conflicting
with the amendment have to be withdrawn (dow) 2009-11-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of amendment 1:2006 to the International Standard IEC 60947-4-3:1999 was approved by
CENELEC as an amendment to the European Standard without any modification.
__________

---------------------- Page: 3 ----------------------

- 3 - EN 60947-4-3:2000/A1:2006
Replace Annex ZA of EN 60947-4-3:2000 by:
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.

Publication Year Title EN/HD Year

IEC 60050-161 1990 International Electrotechnical Vocabulary - -
A1 1997 (IEV) - -
A2 1998 Chapter 161: Electromagnetic compatibility - -


IEC 60085 2004 Electrical insulation - Thermal classification EN 60085 2004


IEC 60269-1 1998 Low-voltage fuses EN 60269-1 1998
A1 2005 Part 1: General requirements A1 2005


IEC 60410 1973 Sampling plans and procedures for - -
inspection by attributes


IEC 60439-1 1999 Low-voltage switchgear and controlgear EN 60439-1 1999
A1 2004 assemblies A1 2004
Part 1: Type-tested and partially type-tested
assemblies


IEC 60664 Series Insulation coordination for equipment within EN 60664-1 Series
low-voltage systems


IEC 60947-1 2004 Low-voltage switchgear and controlgear EN 60947-1 2004
Part 1: General rules + corr. November 2004


IEC 60947-4-2 1999 Low-voltage switchgear and controlgear EN 60947-4-2 2000
A1 2001 Part 4-2: Contactors and motor-starters - A1 2002
A2 2006 AC semiconductor motor controllers and A2 2006
starters


IEC/TR 61000-2-1 1990 Electromagnetic compatibility (EMC) - -
Part 2: Environment -
Section 1: Description of the environment -
Electromagnetic environment for low-
frequency conducted disturbances and
signalling in public power supply systems


1)
IEC 61000-3-2 2000 Electromagnetic compatibility (EMC) EN 61000-3-2 2000
(mod) Part 3-2: Limits - Limits for harmonic current
A1 2001 emissions (equipment input current up to

+ A2 2004 and including 16 A per phase) A2 2005



1)
EN 61000-3-2 is superseded by EN 61000-3-2:2006, which is based on IEC 61000-3-2:2005.

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EN 60947-4-3:2000/A1:2006 - 4 -
Publication Year Title EN/HD Year
IEC 61000-4-2 1995 Electromagnetic compatibility (EMC) EN 61000-4-2 1995
A1 1998 Part 4-2: Testing and measurement A1 1998
A2 2000 techniques - Electrostatic discharge A2 2001
immunity test


2)
IEC 61000-4-3 2002 Electromagnetic compatibility (EMC) EN 61000-4-3 2002

A1 2002 Part 4-3: Testing and measurement A1 2002
techniques - Radiated, radio-frequency,
electromagnetic field immunity test


3)
IEC 61000-4-4 1995 Electromagnetic compatibility (EMC) EN 61000-4-4 1995
A1 2000 Part 4-4: Testing and measurement A1 2001

A2 2001 techniques - Electrical fast transient/burst A2 2001
immunity test


4)
IEC 61000-4-5 1995 Electromagnetic compatibility (EMC) EN 61000-4-5 1995

A1 2000 Part 4-5: Testing and measurement A1 2001
techniques - Surge immunity test


IEC 61000-4-6 2003 Electromagnetic compatibility (EMC) - -
A1 2004 Part 4-6: Testing and measurement - -
A2 2006 techniques - Immunity to conducted - -
disturbances, induced by radio-frequency
fields


5)
IEC 61000-4-11 1994 Electromagnetic compatibility (EMC) EN 61000-4-11 1994
A1 2000 Part 4-11: Testing and measurement A1 2001
techniques - Voltage dips, short interruptions
and voltage variations immunity tests


IEC 61131-2 2003 Programmable controllers EN 61131-2 2003
Part 2: Equipment requirements and tests + corr. August 2003


CISPR 11 (mod) 2003 Industrial scientific and medical (ISM) radio-
6)
+ A1 (mod) 2004 frequency equipment - Electromagnetic EN 55011 200X
disturbance characteristics - Limits and
methods of measurement


7) 6)
CISPR 14-1 - Electromagnetic compatibility - Requirements EN 55014-1 200X
for household appliances, electric tools and
similar apparatus
Part 1: Emission




2)
EN 61000-4-3 is superseded by EN 61000-4-3:2006, which is based on IEC 61000-4-3:2006.
3)
EN 61000-4-4 is superseded by EN 61000-4-4:2004, which is based on IEC 61000-4-4:2004.
4)
EN 61000-4-5 is superseded by EN 61000-4-5:2006, which is based on IEC 61000-4-5:2005.
5)
EN 61000-4-11 is superseded by EN 61000-4-11:2004, which is based on IEC 61000-4-11:2004.
6)
To be published.
7)
Undated reference.

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NORME CEI
INTERNATIONALE
IEC



60947-4-3
INTERNATIONAL


1999
STANDARD


AMENDEMENT 1
AMENDMENT 1

2006-10

Amendement 1
Appareillage à basse tension –
Partie 4-3:
Contacteurs et démarreurs de moteurs –
Gradateurs et contacteurs à semiconducteurs
pour charges, autres que des moteurs,
à courant alternatif

Amendment 1
Low-voltage switchgear and controlgear –
Part 4-3:
Contactors and motor-starters –
AC semiconductor controllers and
contactors for non-motor loads
© IEC 2006 Droits de reproduction réservés ⎯ Copyright - all rights reserved
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
CODE PRIX
U
Commission Electrotechnique Internationale
PRICE CODE
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
Pour prix, voir catalogue en vigueur
For price, see current catalogue

---------------------- Page: 6 ----------------------

60947-4-3 Amend. 1 © IEC:2006 – 3 –

FOREWORD
This amendment has been prepared by subcommittee 17B: Low-voltage switchgear and
controlgear, of IEC technical committee 17: Switchgear and controlgear.
The text of this amendment is based on the following documents:
FDIS Report on voting
17B/1486/FDIS 17B/1510/RVD

Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the maintenance result date indicated on the IEC web site under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be:
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
________________
Page 3
CONTENTS
Modify the title of Clause 3 to read:
3 Definitions, symbols and abbreviations
Insert the following:
3.3 Symbols and abbreviations
Delete the subclause 5.9.
Insert, on page 5, the following:
Annex I (normative) Modified test circuit for short-circuit testing of semiconductor contactors
and controllers
Annex J (informative) Flowchart for constructing bypassed semiconductor controllers tests
Table 17 – Temperature rise limits for insulated coils in air and in oil
Table 18 – Intermittent duty test cycle data

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60947-4-3 Amend. 1 © IEC:2006 – 5 –
Page 11
1 Scope and object
Insert, after the third paragraph, the following new paragraph:
This standard characterizes controllers and contactors for use with or without bypass
switching devices.
Replace, in the sixth paragraph, the first dashed item by the following:
− operation of a.c. and d.c. motors;

Page 13
2 Normative references
Replace the existing text of first paragraph by the following:
The following referenced documents are indispensable for the application 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.
Add, after IEC 60050(161), the following references:
Amendment 1 (1997)
Amendment 2 (1998)
Insert the following new reference:
IEC 60085:2004, Electrical insulation – Thermal classification
Add, after IEC 60269-1, the following reference:
)
1
Amendment 1 (2005)
Replace the reference to IEC 60439-1:1992 by the following:
IEC 60439-1:1999, Low-voltage switchgear and controlgear assemblies – Part 1: Type-tested
and partially type-tested assemblies
)
2
Amendment 1 (2004)
Replace the reference to IEC 60947-1:1999 by the following:
IEC 60947-1:2004, Low-voltage switchgear and controlgear – Part 1: General rules
———————
)
1
 A consolidated edition 3.1 (2005) exists, that includes edition 3.0 and its amendment.
)
2
 A consolidated edition 4.1 (2004) exists, that includes edition 4.0 and its amendment.

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60947-4-3 Amend. 1 © IEC:2006 – 7 –
Replace the reference to IEC 60947-4-2:1995 by the following:
IEC 60947-4-2:1999, Low-voltage switchgear and controlgear – Part 4-2: Contactors and
motor-starters – AC semiconductor motor controllers and starters
Amendment 1 (2001)
)
3
Amendment 2
Replace the reference to IEC 61000-3-2:1995 by the following:
IEC 61000-3-2:2000, Electromagnetic compatibility (EMC) – Part 3-2: Limits – Limits for
harmonic current emissions (equipment input current ≤16 A per phase)
Amendment 1 (2001)
Amendment 2 (2004)
Delete the reference to IEC 61000-4 (all parts).
Add, after IEC 61000-4-2, the following references:
Amendment 1 (1998)
)
4
Amendment 2 (2000)
Replace the reference to IEC 61000-4-3:1995 by the following:
IEC 61000-4-3:2002, Electromagnetic compatibility (EMC) – Part 4-3: Testing and measure-
ment techniques – Radiated radio-frequency electromagnetic field immunity test
Amendment 1 (2002)
)
Add, after IEC 61000-4-4 , the following references:
Amendment 1 (2000)
Amendment 2 (2001)
Add, after IEC 61000-4-5, the following reference:
Amendment 1 (2000)
Replace the reference to IEC 61000-4-6:1996 by the following:
IEC 61000-4-6:2003, Electromagnetic compatibility (EMC) – Part 4-6: Testing and measure-
ment techniques – Immunity to conducted disturbances, induced by radio-frequency fields
Amendment 1 (2004)
)
5
Amendment 2 (2006)

Add, after IEC 61000-4-11, the following reference:
Amendment 1 (2000)
———————
)
3
 To be published.
)
4
  A consolidated edition 1.2 (2001) exists, that includes edition 1.0 and its amendments 1 and 2.
)
5
 A consolidated edition 2.2 (2006) exists, that includes edition 2.0 and its amendments 1 and 2.

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60947-4-3 Amend. 1 © IEC:2006 – 9 –
Insert the following new reference:
IEC 61131-2:2003, Programmable controllers – Part 2: Equipment requirements and tests
Replace the reference to CISPR 11:1997 by the following:
CISPR 11:2003, Industrial, scientific and medical (ISM) radio-frequency equipment –
Electromagnetic disturbance characteristics – Limits and methods of measurement
)
6
Amendment 1 (2004)
Replace the reference to CISPR 14-1:1993 by the following:
CISPR 14-1, Electromagnetic compatibility – Requirements for household appliances, electric
tools and similar apparatus – Part 1: Emission

Page 15
3 Definitions
Replace the existing title by the following:
3 Definitions, symbols and abbreviations
Insert, after the first paragraph the following alphabetical index of definitions:
Reference
A
AC semiconductor controller . 3.1.1.1

B
Burst (of pulses or oscillations) . 3.2.7
Bypassed controller . 3.1.24

C
Controlled operation . 3.1.7
Current-limit function . 3.1.3

D
Defined-point switching (of a semiconductor controller) . 3.1.14.4.1

E
Electromagnetic compatibility, EMC (abbreviation). 3.2.1
Electromagnetic disturbance . 3.2.3
(electromagnetic) Emission. 3.2.2

F
Full-on (state of controllers) . 3.1.10

H
———————
)
6
  A consolidated edition 4.1 (2004) exists, that includes edition 4.0 and its amendment.

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60947-4-3 Amend. 1 © IEC:2006 – 11 –
Hybrid controllers or contactors, form HxA (where x = 4 or 5) . 3.1.2.1
Hybrid controllers or contactors, form HxB . 3.1.2.2

I
Immunity (to a disturbance) . 3.2.9
Instantaneous switching function . 3.1.14.3

L
Load control. 3.1.4

M
Minimum load current . 3.1.11
Minimum load current detection . 3.1.11.1

O
OFF-state. 3.1.12
OFF-state leakage current . 3.1.13
OFF-time. 3.1.23
ON-state. 3.1.9
ON-time. 3.1.22
OPEN position. 3.1.2.3
Operating capability. 3.1.16
Operating cycle (of a controller). 3.1.15
Operation (of a controller). 3.1.14
Overcurrent protective means OCPM. 3.1.21
Overload current profile . 3.1.17

R
Radio (frequency) disturbance . 3.2.4
Radio frequency interference, RFI (abbreviation) . 3.2.5
Ramp-down. 3.1.6
Ramp switching function . 3.1.14.2
Ramp-up. 3.1.5
Random point switching (of a semiconductor controller). 3.1.14.4.3
Rating index . 3.1.18

S
Semiconductor controller (form 4) . 3.1.1.1.1
Semiconductor direct-on-line (DOL) controller (form 5) . 3.1.1.1.3
Switching function. 3.1.14.1
Switching point . 3.1.14.4

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60947-4-3 Amend. 1 © IEC:2006 – 13 –
T
Transient (adjective and noun). 3.2.6
Trip-free controller . 3.1.20
Tripping operation (of a controller) . 3.1.19

V
Voltage surge . 3.2.8

Z
Zero-point switching (of a semiconductor controller) . 3.1.14.4.2

Page 17
3.1.1.1.3
Correct the term to read: “semiconductor direct-on-line (DOL) controller (form 5)”.
Figure 1 – Graphical possibilities of controllers
Insert, after the row "Hybrid controller HxB**", the two following new rows:


Parallel mechanical
contact
Bypassed controller L
T
Semiconductor controller
(Forms 4,5)
IEC  1896/06

Parallel mechanical
contact
Hybrid controller
Bypassed hybrid

c L T
controller
Series

Semiconductor
mechanical

controller
contact


(Forms H × A, H × B)
IEC  1897/06

c
Add, at the bottom of the figure, the following new footnote “ ”:
c
 For other configurations, tests may be suitably adapted by agreement between the user and the manufacturer.

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60947-4-3 Amend. 1 © IEC:2006 – 15 –
Page 19
3.1.2.2
The correction applies to the French text only.
Page 23
3.1.11.1
The correction applies to the French text only.
Add, on page 27, after definition 3.1.23, the following new definition:
3.1.24
bypassed controller
equipment wherein the main circuit contacts of a mechanical switching device are connected
in parallel with the main circuit terminals of a semiconductor switching device, and wherein
the operating means of the two switching devices are co-ordinated

Page 27
Modify the existing text of the note of definition 3.2.5 to read:
“… applied to a radiofrequency disturbance or an unwanted signal. [IEV 161-01-14]”

Page 29
Add, after definition 3.2.9, the following new subclause:
3.3 Symbols and abbreviations
A Final ambient temperature (9.3.3.3.4)
f
C Final case temperature (9.3.3.3.4)
f
EMC Electromagnetic compatibility
EUT Equipment under test
I Current made and broken (Table 8)
c
I Rated operational current (5.3.2.3)
e
I Leakage current after the blocking and commutating capability test (9.3.3.6.3)
F
I OFF-state leakage current (3.1.13)
L
I Leakage current before the blocking and commutating capability test (9.3.3.6.3)
O
I Conventional free air thermal current (5.3.2.1)
th
I Conventional enclosed thermal current (5.3.2.2)
the
I Rated uninterrupted current (5.3.2.4)
u
SCPD Short-circuit protective device
U Rated control circuit voltage (5.5)
c
U Rated operational voltage (5.3.1.1)
e

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60947-4-3 Amend. 1 © IEC:2006 – 17 –
U Rated insulation voltage (5.3.1.2)
i
U Rated impulse withstand voltage (5.3.1.3)
imp
U Power frequency recovery voltage (Table 6)
r
U Rated control supply voltage (5.5)
s

Page 29
5.1 Summary of characteristics
Delete the last dashed item “− switching overvoltages (see 5.9)”.

Page 35
5.3.1 Rated voltages
Modify the first sentence to read:
“A controller or a contactor is defined by …”
5.3.2 Currents
Modify the first sentence to read:
“A controller or a contactor is defined by …”

Page 39
5.4 Utilization category
Replace, on page 41, the second paragraph by the following:
The first digit of the utilization category identification designates a semiconductor switching
device (e.g., within this standard, a semiconductor controller or contactor).

Page 41
5.4.1 Assignment of ratings based on the results of tests
Modify the first sentence to read:
A designated semiconductor controller or contactor with a rating for one utilization category
which has been verified by testing can be assigned other ratings without testing, provided
that:

---------------------- Page: 14 ----------------------

60947-4-3 Amend. 1 © IEC:2006 – 19 –
Page 43
Table 3 – Relative levels of severity
2 2
Replace, in NOTE 1, “(XI ) ” by “(XI ) ”, “T ” by “T ” and “XI” by “XI ” (twice).
e x e
The correction applies to the French text only.
5.5 Control circuits
The correction applies to the French text only.
5.6 Auxiliary circuits
Add, at the end of this subclause, the following new paragraph:
Digital inputs and/or digital outputs contained in controllers and contactors, and intended to
be compatible with PLC’s shall fulfil the requirements of IEC 61131-2.

Page 45
5.8 Coordination with short-circuit protective devices (SCPD)
Modify the existing text of the first paragraph to read:
“ … of the SCPD to be used to provide an adequate protection of the controller or contactor
against short-circuit currents.”
5.9 Switching overvoltages
Delete the title and the text of this subclause.
6.1 Nature of information
Replace, on page 47, the item p) by the following:
p) vacant.

Page 47
6.3 Instructions for installation, operation and maintenance
Replace the existing text of this subclause by the following:
Subclause 5.3 of IEC 60947-1 applies, with the following addition.
For products complying with this standard, the following are specific items to be considered:
− in the event of a short-circuit;

---------------------- Page: 15 ----------------------

60947-4-3 Amend. 1 © IEC:2006 – 21 –
− in the event of temperature rise above 50 K of the metallic radiator surface of the device.

Page 51
8.1.3 Clearances and creepage distances
Replace the existing text of this subclause by the following:
Subclause 7.1.3 of IEC 60947-1 applies with the following note.
NOTE The nature of a semiconductor makes it unsuitable for use for isolation purposes.

Page 53
Add, after 8.2.1.5.2, the following new subclauses:
8.2.1.6 Type-tested components in bypassed controllers
8.2.1.6.1 Switching devices which meet the requirements of their own relevant product
standard shall be considered as partially type-tested devices subject to the following
additional requirements:
a) the temperature rises of mechanical switching devices shall comply with 8.2.2;
b) the making and breaking capacity of mechanical switching devices shall comply with
8.2.4.2;
c) semiconductor switching devices shall comply with 8.2.4.1 for the utilization category
according to the intended ratings of the bypassed controllers.
8.2.1.6.2 For the purpose of setting requirements for bypassed controllers, switching devices
which meet all of the requirements of 8.2.1.6.1, before they are installed, shall be identified as
type-tested components suitable for unrestricted use in a bypassed controller (see Annex J).
8.2.1.7 Dependent components in bypassed controllers
For the purpose of setting requirements for bypassed controllers, switching devices which do
not meet all of the requirements of 8.2.1.6.1, before they are installed, shall be identified as
dependent components suitable only for restricted use in a bypassed controller (see Annex J).
8.2.1.8 Unrestricted use of switching devices in bypassed controllers
When both the mechanical switching device and the semiconductor switching device are
identified as type tested components, these devices shall be arranged and connected to
comply with the assigned rating, duty and the end use intended by the manufacturer. There
shall be no further restrictions.

---------------------- Page: 16 ----------------------

60947-4-3 Amend. 1 © IEC:2006 – 23 –
8.2.1.9 Restricted use of switching devices in bypassed controllers
When either one or both switching devices are identified as dependent components, the
switching devices shall comply with the following:
a) the switching devices shall be combined, rated and tested as a unit;
b) the switching devices shall be interlocked, by any of the following means, either
individually or in combination: electrical, electronic or mechanical means, such that the
mechanical switching contacts shall not be required to make or break overload currents
without direct intervention by the semiconductor switching device;
c) the semiconductor switching device shall be enabled to take over the control of the current
flowing in the main circuit whenever it is necessary to make or break overload currents.
8.2.2 Temperature rise
Replace the existing text of this subclause by the following:
Subclause 7.2.2 of IEC 60947-1 applies, with the following additions.
Temperature rise deviations on the metallic radiator surface of semiconductor devices are
permitted: 50 K in the case where they need not be touched during normal operation.
If the limit of 50 K is exceeded
...