Electrical accessories - Circuit-breakers for overcurrent protection for household and similar installations - Part 2: Circuit-breakers for AC and DC operation

IEC 60898-2:2016 gives additional requirements for single- and two-pole circuit-breakers which, in addition to the above characteristics, are suitable for operation with direct current, and have a rated DC voltage not exceeding 220 V for single-pole and 440 V for two-pole circuit-breakers, a rated current not exceeding 125 A and a rated DC short-circuit capacity not exceeding 10 000 A. This second edition cancels and replaces the first edition published in 2000 and Amendment 1:2003. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) alignment with second edition of IEC 60898-1;
b) introduction of test Icn1.
This publication is to be read in conjunction with IEC 60898-1:2015.

Petit appareillage - Disjoncteur pour la protection contre les surintensités pour installations domestiques et analogues - Partie 2: Disjoncteurs pour le fonctionnement en courant alternatif et en courant continu

L'IEC 60898-2:2016 énonce des exigences supplémentaires pour les disjoncteurs unipolaires et bipolaires qui, au-delà des caractéristiques susmentionnées, sont aptes à fonctionner avec du courant continu et ont une tension assignée en courant continu ne dépassant pas 220 V pour les disjoncteurs unipolaires et 440 V pour les disjoncteurs bipolaires, un courant assigné ne dépassant pas 125 A et un pouvoir de coupure assigné en courant continu ne dépassant pas 10 000 A. Cette deuxième édition annule et remplace la première édition parue en 2000 et l'Amendement 1:2003. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) alignement avec la deuxième édition de l'IEC 60898-1;
b) ajout de l'essai Icn1.
Cette publication doit être lue conjointement avec la IEC 60898-1:2015

General Information

Status
Published
Publication Date
16-Aug-2016
Current Stage
PPUB - Publication issued
Start Date
17-Aug-2016
Completion Date
17-Aug-2016
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IEC 60898-2
Edition 2.0 2016-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electrical accessories – Circuit-breakers for overcurrent protection for
household and similar installations –
Part 2: Circuit-breakers for AC and DC operation

Petit appareillage – Disjoncteurs pour la protection contre les surintensités pour

installations domestiques et analogues –

Partie 2: Disjoncteurs pour le fonctionnement en courant alternatif et en courant

continu
IEC 60898-2:2016-08(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60898-2
Edition 2.0 2016-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electrical accessories – Circuit-breakers for overcurrent protection for
household and similar installations –
Part 2: Circuit-breakers for AC and DC operation

Petit appareillage – Disjoncteurs pour la protection contre les surintensités pour

installations domestiques et analogues –

Partie 2: Disjoncteurs pour le fonctionnement en courant alternatif et en courant

continu
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.50 ISBN 978-2-8322-3553-9

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 60898-2:2016 © IEC 2016
CONTENTS

FOREWORD......................................................................................................................... 3

1 Scope ............................................................................................................................ 5

2 Normative references .................................................................................................... 5

3 Terms and definitions .................................................................................................... 5

4 Classification ................................................................................................................. 5

5 Characteristics of circuit-breakers .................................................................................. 6

6 Marking and other product information ........................................................................... 7

7 Standard conditions for operation in service ................................................................... 8

8 Requirements for construction and operation .................................................................. 8

9 Tests ............................................................................................................................. 9

Annexes ............................................................................................................................. 16

Annex C (normative) Test sequences and number of samples............................................. 16

Figure 6 – Calibration of the test circuit ............................................................................... 14

Figure 18 – Methods of connection of the circuit-breakers in different DC systems ............... 15

Table 1 – Preferred values of rated voltage ........................................................................... 7

Table 2 – Ranges of instantaneous tripping ........................................................................... 7

Table 7 – Time-current operating characteristics ................................................................... 9

Table C.1 – Test sequences ................................................................................................ 16

Table C.2 – Number of samples for full test procedure ......................................................... 18

---------------------- Page: 4 ----------------------
IEC 60898-2:2016 © IEC 2016 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL ACCESSORIES –
CIRCUIT-BREAKERS FOR OVERCURRENT PROTECTION
FOR HOUSEHOLD AND SIMILAR INSTALLATIONS –
Part 2: Circuit-breakers for AC and DC operation
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

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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

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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.

International Standard IEC 60898-2 has been prepared by subcommittee 23E: Circuit-

breakers and similar equipment for household use, of IEC technical committee 23: Electrical

accessories.
This second edition cancels and replaces the first edition published in 2000 and
Amendment 1:2003. This edition constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous

edition:
a) alignment with second edition of IEC 60898-1;
b) introduction of test I .
cn1
---------------------- Page: 5 ----------------------
– 4 – IEC 60898-2:2016 © IEC 2016
The text of this standard is based on the following documents:
FDIS Report on voting
23E/951A/FDIS 23E/976/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.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 60898 series, published under the general title Electrical

accessories – Circuit-breakers for overcurrent protection for household and similar

installations, can be found on the IEC website.
This Part 2 is to be used in conjunction with IEC 60898-1.

Where a particular subclause of Part 1 is not mentioned in this Part 2, that subclause applies

as far as is reasonable. Where this Part 2 states “addition”, “deletion” or “replacement”, the

corresponding requirement, test specification or explanatory material in Part 1 should be

adapted accordingly.
In this standard, the following print types are used:
– Requirements proper: in roman type.
– Test specifications: in italic type.
– Explanatory matter: in smaller roman type.

The committee has decided that the contents of this publication will remain unchanged until

the stability date indicated on the IEC website 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: 6 ----------------------
IEC 60898-2:2016 © IEC 2016 – 5 –
ELECTRICAL ACCESSORIES –
CIRCUIT-BREAKERS FOR OVERCURRENT PROTECTION
FOR HOUSEHOLD AND SIMILAR INSTALLATIONS –
Part 2: Circuit-breakers for AC and DC operation
1 Scope
Clause 1 of IEC 60898-1:2015 is applicable except as follows:
Addition at the end of the first paragraph:

This standard gives additional requirements for single- and two-pole circuit-breakers which, in

addition to the above characteristics, are suitable for operation with direct current, and have a

rated DC voltage not exceeding 220 V for single-pole and 440 V for two-pole circuit-breakers,

a rated current not exceeding 125 A and a rated DC short-circuit capacity not exceeding

10 000 A.

NOTE This standard applies to circuit-breakers able to make and break both alternating current and direct

current.
Delete the last two paragraphs.
2 Normative references
Clause 2 of IEC 60898-1:2015 is applicable except as follows:
Addition:

IEC 60898-1:2015, Electrical accessories – Circuit-breakers for overcurrent protection for

household and similar installations – Part 1: Circuit-breakers for a.c. operation

3 Terms and definitions
Clause 3 of IEC 60898-1:2015 is applicable except as follows:
Addition:
3.5.10.3
time constant

rise time of a prospective direct current to reach a value of 0,63 times the maximum peak

current
T = L/R (ms)
4 Classification
Clause 4 of IEC 60898-1:2015 is applicable except as follows:
---------------------- Page: 7 ----------------------
– 6 – IEC 60898-2:2016 © IEC 2016
4.2 According to the number of poles:
Replacement:
– single-pole circuit-breakers;
– two-pole circuit-breakers with two protected poles.
4.6 According to the instantaneous tripping current (see 3.5.17)
Delete D-Type.
Addition:
4.8 According to the time constant
– circuit-breakers suitable for DC circuits with a time constant of T ≤ 4 ms;
– circuit-breakers suitable for DC circuits with a time constant of T ≤ 15 ms.

NOTE It is assumed that short-circuit currents of 1 500 A are not exceeded in installations in which, due to the

loads connected, time constants in normal service up to 15 ms can occur. Where higher short-circuit currents can

occur, the time constant of T = 4 ms is considered sufficient.
5 Characteristics of circuit-breakers
Clause 5 of IEC 60898-1:2015 is applicable except as follows:
5.3.1 Preferred values of rated voltage
Replacement:
The preferred values of rated voltage are given in Table 1.

Examples of connections of circuit-breakers in DC systems are given in Figure 18.

---------------------- Page: 8 ----------------------
IEC 60898-2:2016 © IEC 2016 – 7 –
Table 1 – Preferred values of rated voltage
AC DC
Circuit-breakers AC circuit supplying Rated DC circuit Rated DC wiring
the circuit-breaker AC voltage supplying the DC voltage examples
circuit-breaker
Single-phase Two wires 125 V or
230 V
(phase to neutral) (unearthed system) 220 V
Single-phase (phase to
earthed middle conductor, 120 V – –
Single-pole or phase to neutral) Figure 18a
Single-phase (phase to
neutral) or three-phase
230/400 V – –
(3 single-pole circuit-
breakers) (3-wire or 4-wire)
Single-phase (phase-to- Two wires
400 V 220/440 V
phase) (earthed system)
Figures 18b, 18c,
Two-pole
18d
Single phase (phase-to- Two wires
a a
120/240 V 125/250 V
phase, 3-wire) (earthed system)
Applicable for DC voltages:

Also for single-pole circuit-breakers to be used in pairs at 250 V DC (respectively 240 V AC) and individually at

125 V DC (respectively 120 V AC).
The rated voltage per pole does not exceed 220 V DC.
Applicable for AC voltages:

NOTE 1 In IEC 60038 the network voltage value of 230/400 V has been standardized. This value progressively

supersedes the values of 220/380 V and 240/415 V.

NOTE 2 Wherever in this standard there is a reference to 230 V or 400 V, it can be read as 220 V or 240 V, and

380 V or 415 V, respectively.
NOTE 3 Circuit-breakers complying with this standard can be used in IT systems.

The manufacturer shall declare in his literature the minimum voltage for which the circuit-

breaker is designed.
Relevant tests are under consideration.
5.3.5 Standard ranges of instantaneous tripping
Replacement:
Table 2 – Ranges of instantaneous tripping
Type Ranges for alternating current Ranges for direct current
B Above 3 I up to and including 5 I Above 4 I up to and including 7 I
n n
n n
C Above 5 I up to and including 10 I Above 7 I up to and including 15 I
n n
n n
6 Marking and other product information
Clause 6 of IEC 60898-1:2015 is applicable except as follows:
---------------------- Page: 9 ----------------------
– 8 – IEC 60898-2:2016 © IEC 2016
Replacement:

c) rated AC voltage with the symbol (IEC 60417-5032:2002-10) and rated DC voltage

with the symbol (IEC 60417-5031:2002-10).

d) rated current without symbol "A", preceded by the symbol of instantaneous tripping (B or

C), for example B 16;

f) rated short-circuit capacity for AC and DC in amperes in one rectangle, without the symbol

A, if valid for both AC and DC (see Example 1 below). If the rated short-circuit capacity is

different for AC and DC this shall be indicated in two adjacent rectangles, without the

symbol A, with the symbol (IEC 60417-5032:2002-10) near the rectangle containing

the AC value and with the symbol (IEC 60417-5031:2002-10) near the rectangle
containing the DC value (see Example 2 below).
Delete j).
Addition:

m) time constant T15 within a rectangle, if applicable, associated with the marking for the

short-circuit capacity at the time constant of 15 ms (see Example 3 below).
Replacement of the first paragraph following l):

If, for small devices, the space available does not allow all the above data to be marked, at

least the information under c) and d) shall be marked and visible when the circuit-breaker is

installed.

The information under a), b), e), f), g), h), i), l) and m) may be marked on the side or on the

back of the device and be visible only before the device is installed.

Alternatively, the information under g) may be on the inside of any cover which has to be

removed in order to connect the supply wires. Any remaining information not marked shall

be given in the manufacturer’s literature.
EXAMPLE 1 6 000
EXAMPLE 2
10 000
6 000
EXAMPLE 3 1 500 T15

The terminals shall be marked with + or – if necessary. Additionally, arrows indicating the

direction of the current are allowed.

Indications on the possible connection diagrams according to Figure 18 shall be given in the

manufacturer's documentation
7 Standard conditions for operation in service
Clause 7 of IEC 60898-1:2015 applies.
8 Requirements for construction and operation
Clause 8 of IEC 60898-1:2015 is applicable except as follows:
---------------------- Page: 10 ----------------------
IEC 60898-2:2016 © IEC 2016 – 9 –
8.6.1 Standard time-current zone
Replacement:
Table 7 – Time-current operating characteristics
Test Type Test Test Initial Limits Result Remarks
current current condition of tripping or to be
AC DC non-tripping time obtained
t ≥ 1 h (I ≤ 63 A)
a B, C 1,13 I Cold No tripping
t ≥ 2 h (I > 63 A)
Immediately Current steadily
t < 1 h (I ≤ 63 A)
b B, C 1,45 I following Tripping increased within
t < 2 h (I > 63 A)
test a 5 s
1 s < t < 60 s (I ≤ 32 A)
c B, C 2,55 I Cold Tripping
1 s < t < 120 s (I > 32 A)
0,1 < t < 45 s (I ≤ 32 A)
Current
B 3 I 4 I
n n 0,1 < t < 90 s (I > 32 A) established by
d Cold Tripping
closing an
0,1 < t < 15 s (I ≤ 32 A)
C 5 I 7 I
n n
auxiliary switch
0,1 < t < 30 s (I > 32 A)
Current
B 5 I 7 I
n n established by
e Cold t < 0,1 s Tripping
closing an
10 I 15 I
n n
auxiliary switch

The term "cold" means without previous loading, at the reference calibration temperature.

8.8 Performance at short-circuit currents
Replacement of the third paragraph:

It is required that circuit-breakers be able to make and to break any value of current up to and

including the value corresponding to the rated short-circuit capacity at rated frequency, at a

power-frequency recovery voltage equal to 105 % (±5 %) of the rated operational voltage and

at any power factor not less or any time constant not greater than the appropriate limit of the

2 2

range stated in 9.12.5. It is also required that the corresponding values of I t lie below the I t

characteristic (see 3.5.13).
9 Tests
Clause 9 of IEC 60898-1:2015 is applicable except as follows:
9.2 Test conditions
Addition after the fourth paragraph:

For direct current, the test voltage (current) shall have a ripple of ω ≤ 5 % or have the

minimum instantaneous value of the voltage (current) no lower than the required test voltage

(current) −5 %
9.10.3.1 General test conditions
Replacement of second paragraph:

For the upper values of the test current, the test is made on each protected pole:

– for alternating current, at rated voltage between phase to neutral with a power factor

between 0,95 and 1;
---------------------- Page: 11 ----------------------
– 10 – IEC 60898-2:2016 © IEC 2016

– for direct current, a time constant of T = 4 ms or, for circuit-breakers marked with T15, a

time constant of T = 15 ms.
9.10.3.2 For circuit-breakers of the B-type
Replacement:

An alternating current equal to 3 I is passed through all poles connected in series, starting

from cold. The opening time shall comply with Table 7.

An alternating current equal to 5 I is then passed through each pole separately, starting from

cold. The opening time shall comply with Table 7.

A direct current equal to 4 I is passed through all poles connected in series, starting from

cold. The opening time shall comply with Table 7.

A direct current equal to 7 I is then passed through each pole separately, starting from cold.

The opening time shall comply with Table 7.
9.10.3.3 For circuit-breakers of the C-type
Replacement:

An alternating current equal to 5 I is passed through all poles connected in series, starting

from cold. The opening time shall comply with Table 7.

An alternating current equal to 10 I is then passed through each pole separately, starting

from cold. The opening time shall comply with Table 7.

A direct current equal to 7 I is passed through all poles connected in series, starting from

cold. The opening time shall comply with Table 7.

A direct current equal to 15 I is then passed through each pole separately, starting from cold.

The opening time shall comply with Table 7.
9.11.1 General test conditions
Addition after the fourth paragraph:

The direct current shall have a ripple of ω ≤ 5 % and a time constant of T = 4 ms (with a

0
−10

tolerance of %) or, for circuit-breakers marked with T15, a time constant of T = 15 ms

0
−10
(with a tolerance of %).
9.11.2 Test procedure
Replacement of the first paragraph:

One set of circuit-breakers is submitted to 4 000 operating cycles at alternating current, and

another set to 1 000 operating cycles at direct current, both at their rated current.

---------------------- Page: 12 ----------------------
IEC 60898-2:2016 © IEC 2016 – 11 –
9.12.3 Tolerances and test quantities
Addition:
– ripple ≤ 5 %
0
−10
– time constant %.
9.12.5 Power factor of the test circuits
Replacement:
9.12.5 Power factor and time constant of the test circuits
Addition:

For DC test currents up to and including 1 500 A, one of the following time constants shall be

used:
T = L / R = 4 ms for devices not marked T15
T = L / R = 15 ms for devices marked T15.

For DC tests currents above 1 500 A and less than or equal to 10 000 A, the tests for all

samples are made at the time constant of T = 4 ms.

NOTE It is assumed that short-circuit currents of 1 500 A are not exceeded in installations in which, due to the

loads connected, time constants in normal service up to 15 ms can occur. Where higher short-circuit currents can

occur, the time constant of T = 4 ms is considered sufficient.
9.12.8 Interpretation of records
Replacement:
9.12.8.1 Interpretation of records in case of AC voltage
a) Determination of the applied and power frequency recovery voltages.
The applied and power frequency recovery voltages are determined from the record

corresponding to the opening operation O, (see 9.12.11.1) made with the apparatus under

test and estimated as indicated in Figure 6a. The voltage on the supply side shall be

measured during the first cycle after arc extinction in all poles and after high frequency

phenomena have subsided.
b) Determination of the prospective short-circuit current.

The AC component of the prospective current is taken as being equal to the r.m.s. value of

the AC component of the calibration current (values corresponding to A of Figure 6a).

Where applicable, the prospective short-circuit current shall be the average of the

prospective currents in all the phases.
9.12.8.2 Interpretation of records in case of DC voltage
a) Determination of the applied voltage and the recovery voltage.

The applied voltage and the recovery voltage are determined from the record taken during

the break test. The voltage on the supply side shall be measured after arc extinction and

after high frequency phenomena have subsided.
b) Determination of the prospective short-circuit current.

NOTE The value of the prospective current is taken as being equal to the maximum value A as determined

from the calibration curve because circuit-breakers according to this standard break the current before it has

reached its maximum value.
The maximum value of the prospective current is indicated as A in Figure 6b.
---------------------- Page: 13 ----------------------
– 12 – IEC 60898-2:2016 © IEC 2016
Replacement:
9.12.11.2 Tests at reduced short-circuit currents
9.12.11.2 Tests at reduced short-circuit currents and at small direct currents
Additional subclauses:
9.12.11.2.3 Tests at reduced DC short-circuit currents

At direct currents the test circuit is adjusted so as to obtain a current of 500 A or 10 × I

whichever is the higher, at a time constant corresponding to the assigned time constant.

Each of the protected poles of the circuit-breaker is subjected separately to a test in a circuit,

the connections of which are shown in Figure 3.

The circuit-breaker is caused to open automatically three times, the circuit being closed once

by the auxiliary switch A and twice by the circuit-breaker itself.
The sequence of operations shall be:
O – t – CO – t – CO

After arc extinction, the recovery voltage shall be maintained for a duration not less than

0,1 s.
9.12.11.2.4 Test at small direct currents up to
...

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