IEC 60947-2 Guide for Low-Voltage Circuit Breakers

IEC 60947-2 : 2006 + A1:2009 + A2:2013 
Low-voltage switchgear and controlgear –
Part 2: Circuit-breakers  
Mohanapriya S
Richa Diptisikha
Nirmal Paul

Chronology
2
IEC 60947-2 2006-05 ED. 4.0
IEC 60947-2 : 2006 + A1:2009
IEC 60947-2 : 2006 + A1:2009 + A2:2013
IEC 60947-2 : 2006 + A1:2009 + A2:2013 + Amend. 3 (Proposed
draft)

PUBLICATION HISTORY
!3
…… Amd 1.0
1997
Amd 2
8-2001
Ed 3.0
2003
Ed 4.0
2006-20
08
Ed 4.0
Amd1.0
2009
Ed 4.0
Amd 2.0
2013
Detailed
Study
Since 1995

Major impact
• Product design
– Evaluation & establishment of DC critical current
– Update catalogue and product insert with new markings, nomenclature
– Suitable for PV application
– Autoreclosure feature to be added in RCD
– De-rating factor products with enclosure
– Suitable for higher radiated radio-frequency electromagnetic fields
• Testing methodology & setup
– Dielectric test setup
– Critical DC current setup ( pneumatic operator , DC current source, load setup
etc)
– Test setup for inclusion of 21st harmonic
– Higher radiofrequency generator
– DC voltage and environmental test set up
4

Major impact
• Certification
– Test as per new table 9b & 9c especially for 1P and 2P circuit breaker
– DC critical current test
– Suitable for PV application
– Establishment of enclosed thermal current
– Suitable for zigbee, bluetooth application
– Verification for selectivity
5

Index
IEC 60947-2
:2013 
Draft
Clause 1.0 to
7.0
Annexure
P and R
Clause
8.0 
Annexure
A to O
Glimpses of
Amendment 2

Highlight of Amendment 2 for clause 1 to 7
• Editorial change: discrimination word replaced by selectivity.
• Definition changed:
2.17.1. Over current discrimination replaced by Overcurrent selectivity.
2.21. Overload current setting ( Ir ) added.
4.3.5.2.2. Rated service short circuit breaking capacity ( Ics )
Table 1: Standard ratios between Ics and Icu VOID
• Additional markings needed to be mentioned on product itself or product catalogue.
1. Ir , Ii needed to be marked on product .
2. Tightening torque, minimum cable cross section needed to be mentioned in product
catalogue or leaflet.
• Lists of construction break has added following considerations :
1. Creation of 2 pole from 3 pole by removing center pole : No construction break.
2. Replacement of the trip unit in one pole by a link in 2-pole and 4-pole variants:
No construction break 7

• 8.3.1.4 Alternative test programmes for circuit- breakers having both
three pole and four pole variants changed to
8.3.1.4 Alternative test programmes for circuit breaker of a given frame
size and design having a different number of poles.
8.3.2.6.7 : Verification after short-circuit tests includes:
there shall be no damage to the insulation on conductors used to
wire the device.
8
Highlights of Amendment 2 for clause 8

Annex – Undergone change
Annex Title Amd 2 Amd 3
Annex A (normative)
Co-ordination under short-circuit conditions between a circuit-breaker and another short-
circuit protective device associated in the same circuit
A A
Annex B (normative) Circuit-breakers incorporating residual current protection B
Annex C (normative) Individual pole short-circuit test sequence C
Annex D (normative) Vacant
Annex E (informative) Items subject to agreement between manufacturer and user E
Annex F (normative) Additional tests for circuit-breakers with electronic over-current protection F F
Annex G (normative) Power loss
Annex H (normative) Test sequence for circuit-breakers for IT systems H
Annex I
Annex J (normative) Electromagnetic compatibility (EMC) – Requirements and test methods for circuit-breakers J
Annex K (informative) Glossary of symbols related to products covered by this standard K
Annex L (normative) Circuit-breakers not fulfilling the requirements for overcurrent protection L
Annex M (normative) Modular residual current devices (without integral current breaking device) M
Annex N (normative)
Electromagnetic compatibility (EMC) – Additional requirements and test methods for devices  
not covered by Annexes B, F and M
N
Annex O (normative) Instantaneous trip circuit-breakers (ICB) O
Annex P (normative) DC Circuit- breakers for use in photovoltaic (PV) applications P
Annex Q Vacant
Annex R (normative) Circuit- breakers incorporating residual current protection with auto- reclosing functions R
9

Highlights of Annexure in Amendment 2
• Annex A-
• Editorial corrections and two sub clauses added
• Annex B, L, M & O-
• CBRs having variants with different number of poles test variant with
the greatest number of poles, also no construction break no
additional test is required or else test all different variants
• Annex C & H-
• Recovery voltage requirements included
• Annex E-
• Editorial corrections and special test added
• Annex K-
• Editorial changes and new symbols added 10

11
IEC 60947-2 : 2013 (Proposed
Draft)
Last date of comments: Mar 8,
2013

• This standard applies to circuit-breakers, the main contacts of which are
intended to be connected to circuits, the rated voltage of which does
not exceed 1 000 V a.c. or 1 500 V d.c.; it also contains additional
requirements for integrally fused circuit-breakers.
Note: Circuit breakers rated above 1000V a.c. for special applications
may also be tested to this standard.
12
1.1 Scope & object
Added

Interpretation
• Standard is silent about the following:
1. Higher limits of voltage.
2. examples of special applications.
13

Note 2 Attention is drawn to the different requirements for the minimum required
percentage of Ics for utilisation categories A & B ,in accordance with Table 1
Table 4
14
Deleted

NOTE A circuit-breaker of selectivity category A may have an intentional
short- time delay provided for selectivity under conditions other than those
of short circuit, with a short-time withstand current less than that according
to Table 3. In that case, the tests include test sequence IV (see 8.3.6) at the
assigned short-time withstand current.
Table 4 –Selectivity categories
15
These circuit-breakers may provide selectivity, under short-circuit
conditions, by other means. This selectivity cannot be assessed on
the
basis of time-current curves only. Information is usually given in the
manufacturer documentation.

Interpretation
• Note 2 is deleted as it is linked with Table 1 which is removed.
• Sequence IV is mandatory for MCCB of category A having intentional
short time delay provided for selectivity under conditions other than
that of short circuit.
• For Sequence IV:
Icw ≥ to the maximum short time release setting current
Withstand time ≥ to the maximum delay provided in the release.
• Suppose MCCB is having 100ms time delay, and Max STS setting: 8Ir,
then test prameters are:
Icw: ≥ 8Ir
Withstand time: ≥ 100ms
16

8.3.2.1
GENERAL REQUIREMENTS:
If a circuit-breaker may be used in specified individual enclosures and has been tested in free air, it
shall be additionally tested in the smallest of such enclosures stated by the manufacturer, using a
new sample, according to 8.3.5, at Ue max/corresponding Icu, with release settings at maximum
(see note 1 to Table 10).
If a circuit-breaker may be used in specified individual enclosures and has been tested in free air, it
shall be additionally tested in the smallest of such enclosures stated by the manufacturer, using a
new sample, for each of the following:
a) A test according to 8.3.5, at Uemax, and corresponding Icu, with release settings at maximum
(see table foot note a of Table 10)
b) A test according to the general conditions of 8.3.2.5 on a circuit-breaker having a maximum Ith,
at the conventional enclosed thermal rating Ithe (see 4.3.2.2). The temperature rises shall
meet the requirements of 7.2.2 except that the temperature rise of the terminals shall not
exceed 70 K.
NOTE: The value of Ithe obtained from this test is applicable to the individual enclosure. Different
values of Ithe may apply to other enclosure arrangements e.g. an assembly to IEC 61439-2
Replace with
17

8.3.2.1
IMPLICATION:
If we test our breakers are tested in free air then we need to test them for 8.3.5 and
additionally for T.R as 7.2.2 at conventional enclosed thermal rating (Ithe), but the
T.R of
terminals for external connections should not be >70K.
NOTE: The value of Ithe obtained from this test is applicable to the individual
enclosure. Different values of Ithe may apply to other enclosure arrangements
e.g. an assembly to IEC 61439-2
18

8.3.3.1.4
Additional test for definite time-delay releases
b) Non-tripping duration
This test is made under the same conditions as for the test of item a) above for both
overload and short-circuit releases:
Firstly, the test current equal to 1,5 times the current setting is maintained for a time
interval equal to the non-tripping duration stated by the manufacturer; then, the current is
reduced to the rated current and maintained at this value for twice the time-delay stated by
the manufacturer. The circuit-breaker shall not trip.
In b) Non-tripping duration, replace the existing “rated current” by “the value
corresponding to
the overload current setting (Ir)”
IMPLICATION:
According to earlier wordings ,If the pick up current (Ir) was 0.6 In then after passing 1.5 Ir it
should be immediately switched to In but actually it should be Ir.
Its an editorial change to avoid any ambiguity.
Replace with
19

8.3.3.2 (Newly added)
Tests for Dielectric properties:
Add the following new addition (v) at the end of 8.3.3.2
Circuit-breakers having a rated insulation voltage > 1000 V a.c. shall be tested at a
test
voltage of Ui + 1 200 V a.c. r.m.s. or 2 Ui , whichever is greater.
EXPLANATION:
In dielectric properties tests, the Power-frequency withstand verification of soild
insulation
wasn't mentioning about the test procedure of those breakers which were having ac
Ui > 1000V. It is mentioning about only DC Ui upto 1500V.
20

8.3.9(Newly added Clause)
8.3.9 Critical d.c. load current test
This test applies only to circuit-breakers with d.c. ratings. The circuit-breaker condition and method of installation shall be as
specified in 8.3.2.1, and the test circuit in accordance with 8.3.3.5.2 of IEC 60947-1 except that the fusible element need
not be used. Samples to be tested shall be selected according to Table 10 – sequence I, except that for application of note
g, construction breaks relative to the over-current tripping devices shall not be considered. The test shall be made at the
maximum operational d.c. voltage Uemax assigned by the manufacturer to the circuit-breaker. For circuit-breakers fitted
with adjustable releases, the test shall be made with the releases set at the maximum. In case of circuit-breakers with
dependent manual operation, the circuit-breaker shall be operated with an operating speed, during actuation, of 0,1 m/s ±
25 %, this speed being measured at the extremity when and where the operating means of the test apparatus touches the
actuating means of the circuit-breaker under test. For rotary knobs the angular velocity shall correspond substantially to the
above conditions, referred to the speed of the operating means (at its extremities) of the circuit-breaker under test. The
circuit-breaker shall be closed and opened 10 times on to each of the test currents listed below. If the direction of current
flow is specified by the manufacturer, the test shall be made with the current flowing in the specified direction, as indicated
by the polarity and line/load marking; if not, 5 operations shall be made in the forward direction, and 5 in the reverse
direction. During each CO cycle, the circuit-breaker shall remain closed for a time sufficient to ensure that the full current
is established, but not exceeding 2 s. The time constant shall be equal to 2 ms; at the discretion of the manufacturer, a
higher value may be used instead and stated in the test report.
The number of operating cycles per hour shall be in accordance with Table 8. The arcing time during the test shall be recorded
and shall not exceed 1 s. The test current values shall be: 4 A, 8 A, 16 A, 32 A and 63 A d.c.; the critical value is
determined by taking the maximum mean arcing time, for each direction of current if applicable. The highest and lowest
values of test current shall demonstrate shorter mean arcing times than the critical value; if necessary, the range of test
currents shall be extended upwards or downwards by applying a 2 times ratio as many times as necessary to find the critical
value. The tolerances shall be in accordance with 8.3.2.2.2. Following this test, the same sample shall be subjected to 50
operations, under the same conditions, at the current and in the direction corresponding to the critical value. After this
test, the dielectric withstand shall be verified according to 8.3.3.5.
21

8.3.9
EXPLANATION:
This test is similar to operational performance capability with current in Seq1.
TO FIND TEST CURRENT (CRITICAL):
• To find the critical current we need to find mean arcing time by testing for 4 A, 8 A, 16 A, 32 A and 63 A d.c.
• The highest and lowest values of test current shall demonstrate shorter mean arcing times than the critical value.
• If necessary, the range of test currents shall be extended upwards or downwards by applying a 2 times ratio as many times as
necessary to find the critical value.
To Find Mean Arcing Time:
• CB needs to be closed and opened 10 times on to each of the test currents.
• The the polarity and line/load marking is mentioned then all 10 operations is to be done in that direction, if not mentioned then 5 operations
shall be made in the forward direction, and 5 in the reverse direction.
TEST PROCEDURE:
• In case of circuit-breakers with dependent manual operation , mechanism actuation speed of 0,1 m/s ± 25 % is to be maintained.
• During each CO cycle, the circuit-breaker shall remain closed for a time sufficient to ensure that the full current is established, but not
exceeding 2 s.
• The time constant shall be equal to 2 ms; at the discretion of the manufacturer, a higher value may be used instead and stated in the test
report.
• The number of operating cycles per hour shall be in accordance with Table 8.
• The arcing time during the test shall be recorded and shall not exceed 1 s."
Once the Critical current is obtained the same sample shall be subjected to 50 operations
under the same conditions.
After this test, the dielectric withstand shall be verified according to 8.3.3.5.
IMPLICATION:
This new clause has to be considered while offering a DC breaker. 22

8.5
Special tests – Damp heat, salt mist, vibration and shock
Newly added
The following special tests shall be made either at the discretion of the manufacturer or according to
agreement between the manufacturer and user (see 2.64 of IEC 60947-1). As special tests, these additional
tests are not mandatory, and it is not necessary for a circuit breaker to satisfy any of these to conform to
this standard.
Annex Q of IEC 60947-1 applies.
Where Table Q.1 of IEC 60947-1 calls for verification of operational capability, this shall be made carrying out
the routine tests to 8.4 of this standard , except for the dielctric tests of 8.4.5, which are covered by the
tests of table Q.1 of IEC 60947-1
Replace the existing third paragraph by the following new paragraph:
During the test sequences according to Table Q.1 of IEC 60947-1, only the final verification of operational
capability is required. It shall be made by carrying out the routine tests to 8.4 of this standard, except for
the dielectric tests of 8.4.5, which are covered by the tests of Table Q.1 of IEC 60947-1
Replace with
23

8.5
IMPLICATION:
• Table Q.1 has 3 different verification of operational capability
• In TableQ.1 of IEC 60947-1 "only" the verification of operational capability is
required.
• It’s an editorial change made, to avoid any ambiguity.
24

Annex F (4.1.2)
NOTE 2 (edition 4.0-2009)
This test current for option b) has at least the following harmonic content of the
fundamental component:
– third harmonic >60 %; – fifth harmonic >14 %; – seventh harmonic >7 %.
Higher harmonics may also be present.
In existing NOTE 2 (Draft)
add a fourth dashed item as follows:
- twenty-first harmonic >1 %;
In existing NOTE 2,replace the existing sentence following the indents by the following new
sentence:
Other harmonics may also be present
Changes to
25

IMPLICATION:
• In the test waveform presence of 21st harmonics with >1% made compulsory.
Effect on electronics parts needs to be validated.
• The word ‘Higher’ is replaced by ‘Other’ in the sentence
"Higher harmonics may also be present.“
• Testing agencies have to upgrade themselves if required.
26

Annex J (J.1)
Changes to
IMPLICATION:
Importance is given to operating freq of mobile phones in test currents. 27

Annex J (J.2.3)
Radiated radio-frequency electromagnetic fields:
First sentence of the sixth paragraph:
For step 1, the frequency shall be swept over the ranges of 80 MHz to 1 000 MHz, 1 400 MHz
to 2 000 MHz in accordance with Clause 8 of IEC 61000-4-3.
Existing last paragraph :
For step 2, to verify the functional characteristics, the test shall be performed at each of the
following frequencies: 80; 100; 120; 180; 240; 320; 480; 640; 960; 1 400; 1 920 the operation
being verified after the field at each frequency has stabilized.
Replace the existing first sentence of the sixth paragraph by the following:
For step 1, the frequency shall be swept over the ranges of 80 MHz to 1 000 MHz, 1 400 MHz
to 2 000 MHz, and 2 110 MHz to 2 700 MHz, in accordance with Clause 8 of IEC 61000-4-3.
Replace the existing last paragraph by the following:
For step 2, to verify the functional characteristics, the test shall be performed at each of the
following frequencies: 80; 100; 120; 180; 240; 320; 480; 640; 960; 1 400; 1 920, 2 150 and 2
450 MHz, the operation being verified after the field at each frequency has stabilized.
Changes to
28

Annex J (J.2.3)
IMPLICATION:
• In step 1 of the test
Higher band of frequencies 2110MHz to 2700MHz have been included in the tests.
• In step 2 of the test
To find out the functional characteristics two more additional frequencies of
2150MHz and 2450Mhz have been included.
• The test frequencies have become more severe.
29

Annex A
• Editorial changes specifying “the manufacturer” to consider operating
characteristics of the combination between C1 and SCPD (C2 or fuse) at
various instants.
• Replacing a sub-clause – “Tests for verification of selectivity between
circuit-breakers” by “Consideration of selectivity by desk study”.
30

Annex A  
To ensure co-ordination under short-circuit conditions between a circuit-breaker (C1) and
another short-circuit protective device (SCPD) associated with it in the same circuit, it is
necessary to consider the characteristics of each of the two devices as well as their
behaviour as an association.
To ensure co-ordination under short-circuit conditions between a circuit-breaker (C1) and
another short-circuit protective device (SCPD) associated with it in the same circuit, it is
necessary for the manufacturer to consider the characteristics of each of the two
devices as well as their dynamic behaviour as an association.
31
Replace with

A.5 Verification of selectivity
In certain cases, tests at Is are necessary on the association
In certain cases, tests on the association will show a higher level of Is is
obtained than shown by a desk study
32
Replace with
A.5.2 Tests for verification of selectivity between circuit-breakers.
A.5.2 Consideration of selectivity by desk Study
- A.5.2.1 Selectivity in the overload zone
- A.5.2.2 Determination of selectivity in the fault current (short-circuit) zone
- A.5.2.3 Determination of selectivity limit current for specific installation
conditions.
Replace with

Implications
• By replacing sub clause “Tests for verification of selectivity between
circuit-breakers” by “Consideration of selectivity by desk study” standard
is not clear about how to test for verification of selectivity.
• There is contradiction between the note given in Table 4 and details given
in Annex A 33
These circuit-breakers may provide selectivity, under short-circuit
conditions, by other means. This selectivity cannot be assessed on
the
basis of time-current curves only. Information is usually given in the
manufacturer documentation.

Annex N
34
Performance criterion B applies, except for devices where the application of power
to the terminals will cause the device to operate (case 1 and case 2a in the figures
below). In this case, the change of status of the circuit-breaker is acceptable.
A new figure showing the test configuration for surges is added
Replace with
It supplements Annex J, for test conditions and acceptance criteria specific to
these devices.

Implications
• Standard is silent about the performance criteria that applies at case 1
and case 2a in fig N.1.
35

New Annexure added : Annex P and Annex R
• Annex P
– PV Systems an overview
– Competitors’ study
– Standard requirements
• Annex R
– CBAR an overview
– Competitors’ study
– Standard requirements
37

General Terms used in PV system
• PV cell combined series and parallel connection represents a module
• PV module
– Physical unit, connected in series as a string
• PV string
– Defines system voltage, connected in parallel as an array
• PV array
– Up to incoming terminals of inverter, possibly divided into sub-arrays
• Inverter
– Conversion of the supplied energy, feeding into mains 38
Photovoltaic system an overview

Photovoltaic system an overview
39
Voltage and current levels
•PV Cell
oCurrent 3.5A to 14 A
oVoltage 0.5V
•Module
o36 to 120 cell connected in series
oVoltage 12V to 60 V
•Strings & Array
o V & I depends on requirement (MW or KW
generation requirement of the plant)
oMarket scenario at PV generation plant
oMax. voltage 1500V, current depends on generation
capacity of plant, achieved by connecting string in
parallel.
•Ambient
o-25 °C to + 70 °C
Where: Ir Maximum reverse current
nsp Number of strings connected in parallel
Isc Short-circuit current of a solar module/string
Faults Cause Fault level Protection
Partial
Shadowing
Trees, buildings, birds
etc.,
Over voltage and
Diodes
Clouding Normal currents
Reverse currents
Module short circuit
Fault current Ir=
(nsp-1)Isc Fuses or
Circuit
breakers
Back feeding
High fault currents(Grids, Storage
batteries)
Reverse current

Competitors’ have….
40
ABB
S
c
h
n
ei
d
e
r

Unit
ABB Schneider
MCB MCCB
Switch
disconnectors
MCB MCCB Switch disconnectors
Protection of String level Parallel switchgear Inverter String level Parallel switchgear Inverter
Breaker series S800PV-S
Tmax-PV  
(disconnector)
S800PV-M
Acti 9 C60DC-
PV
Compact NSX200 TM
DC PV
Interpact INS PV, 
Masterpact NW 20 HA DCD-
PV
Current rating A 10-125 160-1600 32,63,125 `1-25 80-200 32-4000
Voltage Rating VDC 1200 1100 1200 800 1000 400-1000
Breaking
Capacity
Icu kA 5
Icm & Icw,1s (1.9 -
19.2)
1.5 1.5 10
Ambient temp. °C -25 to +60 - - Max 70 deg. De-rating table given above 40 °

Annex P - DC Circuit- breakers for use in
photovoltaic (PV) applications
P.1 General
P.1.1 Scope and object
This annex applies to DC circuit- breakers, rated up to 1500 V d.c., intended for
use with photovoltaic (PV) systems, and hereafter referred to as "PV circuit -
breakers".
Circuit- breakers used in PV systems are subjected to electrical, environmental
and operational conditions which differ from the general conditions taken into
account in the body of this standard. The requirements have thus been adapted
to reflect these conditions of use.
The object of this annex is to state:
– the requirements for circuit - breakers to be used on the DC side of PV
applications;
– the tests intended to verify the product performances and their maintaining
after exposure to the PV service environmental conditions.
41

Changes
IEC 60947-2 ed.4 amd 3 (A.C &
D.C)
IEC 60947 ed.4 amd 3 - Annex P (Photavoltaic)
Definition -
Critical load current ( ICRIT)  
Value of breaking current, within the range of service conditions, at
which the arcing time is significantly extended
Characteristics
Impulse withstand voltage
depends on rated operational
voltage, supply system & over
voltage category (Annex H)

Product
information
-
item 5.2 b), 
– "PV" or "Photovoltaic", either in the type designation or associated with
the rated char. 
– IEC 60947 - 2 Annex P. 
item 5.2 c), 
– method and diagram of series connection of poles as necessary for each
rating;  
– appropriate connection to the PV generator and load if applicable ;  
– appropriate connection to "+" and " - " polarities if applicable;  
– thermal current derating for ambient temperatures above 40°C;  
– operational characteristics between – 25 °C and + 70 °C.
Ambient air
temperature
6.1.1 Limits -5°C to +40°C P6.1 Limits -25°C to +70°C
Constructional
requirements
7.1 creepage distanse as per
IEC 60947 - 1 Table 15
P7.1 creepage distances at terminals between opposite polarities and
between live parts and the enclosure or mounting plate shall meet the
values of IEC 60947 - 1 Table 15 multiplied by 1.5. This requirement
does not apply to internal creepage distances.
42
Annex P- Consolidation

Changes IEC 60947-2 ed.4 amd 3 (A.C & D.C) IEC 60947 ed.4 amd 3 - Annex P (Photavoltaic)
Performance
requirements 
7.2.4.1 Overload performance P7.2 ; 7.2.4.1 no tests to this clause are required
7.2.4.2 for operational performance capability Table P7.2
Annex H- Test sequence for circuit-breakers for
IT systems
Due to the installation rules defined in IEC 60364 -7-712,
The risk of a double fault to earth does not need to be
taken in to consideration. Therefore, annex H is not
applicable to PV circuit- breakers.
Type test
8.3.1.2 Tests omitted from sequence I and made
separately
P.8.3.1 Test sequences, With reference to 8.3.1.2, tests
omitted from sequence I need not be made if the PV
circuit breaker is derived from an a.c. or d.c. circuit -
breaker on which identical or more severe tests have
already been conducted, except that tripping
characteristics conducted in a.c. do not cover d.c.
characteristics.
8.3.1.4 Alternate test programme for circuit
breakers having both three pole and four pole
variants
With reference to 8.3.1.4, alternative test programmers'
do not apply to PV circuit - breakers
43

44
Type test
8.3.2.1 General test conditions
P.8.3.2 General test conditions  
Regardless of marking of connections ("+" or "- "
polarities and generator or load), samples shall be
selected and tested according to column "terminals not
marked line/load".
8.3.2.2.5 Time constant of the test circuit -
Table 16 of 60947-1 , where Time constant
varies (5ms to 15ms) depending on breaking
capacity, 2ms for critical load test.
P.8.3.2 Time constant 1ms
8.3.2.6.4 Test procedure
P.8.3.2. 4- pole circuit- breakers, the additional
sequence of operations on the fourth pole and its
adjacent pole is not applicable
8.3.3.3.3 Operational performance capability
without current as per Table 7
P.8.3.3 Test sequence I 
Operational performance capability without current as
per Table P.2
8.3.3.3.4 operational performance capability
with current as per Table 7
P.8.3.3 Operational performance capability with
current as per Table P.2 Regardless of markings for
connections ("+" or " – “polarities and PV generator or
load), half of the operations shall be made with the
currents flowing in the forward direction, the other half
with the reverse direction.
8.3.3.4 overload performance test 8.3.3.4 overload performance test not applicable

Type test
8.3.9 Critical d.c. load current test  
closed & opened 10 times, as per the current
flow direction specified by manufacturer. If
direction not specified 5 times in forward & 5
time in reverse direction current flow. 
The time constant shall be equal to 2 ms,
higher value may be used instead and stated
in the manufactures test report. 
Operational performance verification - 50
operations
P.8.3.9 Critical load current test 
The circuit- breaker shall be closed and opened 10
times on to each of the test currents, 5 times with
the current flowing in the forward direction, and 5
times with the current flowing in the reverse
direction. 
Time constant 1 ms. 
During the operational performance verification, the
breaker shall be subjected to 100 operations
instead of 50. This verification need not be made if
the critical current is equal to or greater than the
rated current.
-
P.8.3.10 Thermal cycling test 
50 cycles- (1 hour at – 40 °C , 1 hour at + 85°C.
Temp. change rate shall be 1 K/min) 
verification of temp. rise at the main terminals in
accordance with 8.3.2.5
-
P.8.3.11 Climatic test added 
climatic tests of IEC 60947 -1 Annex Q, category
B: environment subject to temperature and
humidity, except that the dry heat test and the low
temperature test are not required. Verification as
per clause 8.5 45

Highlights
• Ambient air temperature -25°C to +70°C
• De-rating table above 40 °C
• Tested under “terminals not marked line/load”
• Creepage distance increased 1.5 times
• Critical load test 100 operations at 1 ms
• Thermal cycle test, 50 cycles limits widened -40°C to 85°C
46

Annex R (Normative)
• Circuit breaker incorporating residual current protection with auto-reclosing functions.
• Objective of this annex specifies the conditions of temporary faults like lightning surges or
temporary earth leakage at on-site etc.
• Based on relevant requirements of Annex B of IEC 60947-2.
Comparison with IEC 61008-1 :
• Value of IΔn in 61008-1: 0.006 - 0.01 - 0.03 - 0.1 - 0.3 - 0.5 A
• Value of IΔn in Annex B of IEC 60947-2 : 0.006 - 0.01 - 0.03 - 0.1 - 0.3 - 0.5
- 1 - 3 - 10 - 30A
Abbreviations used:
• CB : Circuit Breaker
• CBR: Circuit-breaker incorporating residual current protection
• CBAR: Circuit-breaker incorporating residual current protection with auto-reclosing functions
• ARD: Auto reclosing devices
47

Overview
• Application areas of CBARs:
1. unmanned mobile telecommunication stations in the mountain.
2. Security systems.(detectors & Alarms)
3. Central lighting commands
4. Traffic light systems.
• Applies also to any ARD which will function as CBAR if integrated with
CBR.
48

ABB F2C ARI
49
Our competitor ABB product F2C-ARI & F2C-ARH is in market.
F2C-ARI & F2C-ARH are used with ABB’s F200 & FH200 series of RCCB to
avoid nuissance tripping.

Function of CBAR
• Fault occurs-! CBAR performs 3 reclosing attempts.
• If negative output! locked state
via 1NO+1NC signal change over contact
indicated by LED.
The locked state can be reset:
• locally
by manually moving the mobile element on the front of the device to the
OFF position and subsequently to the ON position. The device will reset and
automatically reclose the circuit breaker.
• remotely
by means of a close command (NO contact) which resets the device and
close the circuit breaker.
50

Annex R
Clause Annex B , IEC 60947-2 Ed. 4.0, 2013 Annex R , IEC 60947-2 Ed.4.0 (Proposed draft)
R.1 .
Scope &
Object
• Applies to CB compliance to IEC
60947-2 providing residual current
function as an integrated feature
(CBRs).  
 
• Object includes residual current
function, normal & abnormal circuit
conditions.
• Applies to CB compliance to IEC 60947-2 providing
residual current protection with auto reclosing
functions incorporated (CBARs). 
• Also applies to ARD supplied separately to CBR
which will function as CBAR when integrated. 
• Object includes residual current function with
auto reclosing, normal, abnormal as well as
temporary fault conditions.
R.2.
Definition
s
Definitions are as per Clause 2 of IEC
60947-2 & Clause B.2 of Annex B
Some definitions are added w.ref to Annex B like: 
1. Auto reclosing 
2. Auto reclosing operating residual current (IΔar) 
3. Intermittent monitoring voltage 
4. Continuous monitoring voltage.
R.3.
Classificat
ion
Classifications are as per Clause 2 of IEC
60947-2 & Clause B.2 of Annex B.
In Addition to Annex B, 
On the basis of a) Method of construction 
1.Integral type 
2. Semi integral type 
3. Independent type 
b) Method of autoreclosing 
1.Time delay type TD 
2. Earth leakage monitoring type M
R.4.
Characteri
stics
Characteristics as per Clause 4 & Annex
B.4
Addition to Annex B , Max. value of IΔar is 0.5 (IΔn)

Clause
Annex B , IEC 60947-2 Ed. 4.0,
2013
Annex R , IEC 60947-2 Ed.4.0 (Proposed draft)
R.5. Marking
& Instructions
Clause 5 & annex B.5
In addition to annex B,  
1. indication of “auto reclosing”---------on the product itself 
2. Indication of mode selection as “auto reclosing”, manual
reclosing- -------------on the product itself 
1. Method of checking the status of indication lamps.- in
Catalogue 
2. CBARs dependent on line voltage , procedures of protection ,
replacement, warranty etc should be mentioned.CBARs
connected to earth terminal , procedure of connections should
be mentioned- in Catalogue

R.6. Normal
service,mounti
ng & transport
condition
Clause 6 of IEC 60947-2 Clause 6 of IEC 60947-2
R.7.1. Design
requirements
Clause 7.1 and Annex B.7.1
In addition to Annex B: 
Mode selection- Ensure that Auto/Manual Reclosing should be
through switch. 
Indication lamps- Ensure that for e.g: normal operation mode,
Auto-reclosing mode, burnout state of built in fuse etc. should
be visible. 
CBARs using line voltage: If, then proper SCPD should be
connected to circuit (all pole/ single pole ) for safety. 
CBARs using batteries: If, then batteries shall have Product
certificate / test reports.

R. 7.2 Operating Requirements
54
Clause
No. Design requirements Monitoring Parameters Conditions checked
Complian
ce
checked
by
R.7.2.1 Unwanted auto reclosing
If CBAR tripped due to SC/OL, should not auto
reclose
R. 8.2
R.7.2.2
Auto-Reclosing functions
by Permanent Earth
leakage faults
intermittent/continuous
monitoring voltage: 
voltage ≤ 25V a.c / 60V d.c  
ON time shall be ≤ 0.2sec 
OFF time shall be 10sec ≤ t ≤
30sec 
Overall monitoring time: 1 hr
Case 1: Presence of fault: 
No o/p voltage generation after some time as
declared by manufacturer. 
CBAR should not reclose. 
Case 2: Absence of fault:  
shall auto reclose but  
If auto reclosing occured > 2 times within 30
mins, the auto reclosing function shall be
disabled for safety.
R. 8.3.1
R.7.2.3
by Temporary Earth
leakage faults
IΔar 
Reclosing time after clearing
the residual current ≤ 30secs
CBAR tripping due to Permanent EL faults:
should not auto reclose. 
CBAR tripping due to temporary EL faults:
shall reclose if residual current ≤ IΔar 
Manually opened: shall not be reclosed even
in Auto Reclosing mode.
R.8.3.2
R.7.2.4
by Temporary Earth surges
Tripping due to Temporary Surges:  
shall auto-reclose.
R.8.4
R.7.2.5 Isolating function

shall provide an isolating distance in OPEN
position to verify isolation.
R.8.5
R.7.2.6
Residual short -circuit
making & breaking
capacity
shall make,carry for specified time and break
residual sc currents
R.8.6
R.7.2.7
Effects of environmental
conditions shall operate satisfactorily.
R.8.7
R.7.2.8
Independent type Auto
Reclosing devices Shall comply with Annex R.
R.8.8

Sequence
(Sample )
TEST Subclause
1.
Test of unwanted reclosing R 8.2
Test of auto-reclosing functions R 8.3
Test of auto-reclosing functions by temporary surges R 8.4
2 Verification of isolating functions R 8.5
3 Verification of residual short circuit making & breaking
capacity
R 8.6
4
Verification of effects of environmental conditions for auto
reclosing functions
R 8.7
Tests for Integral/semi-integral type
CBAR

Sequence
(Sample )
TEST Subclause
1.
Test of unwanted reclosing R 8.2
Test of auto-reclosing functions R 8.3
Test of auto-reclosing functions by temporary surges R 8.4
Test of dielectric properties 8.3.3.2
Verification of isolating functions R 8.5
2. Verification of residual short circuit making & breaking
capacity
R 8.6
3.
Rated service short circuit breaking capacity 8.3.4
Verification of auto reclosing functions R 8.7.a)
4.
Verification of effects of environmental conditions B 8.11
Verification of auto reclosing functions R 8.7.e)
5.
Verification of resistance against unwanted tripping B.8.6
Verification of EMC B 8.12
Verification of auto reclosing functions R 8.7.f)
Table R.1 (Independent type
CBAR)

Highlights
• With reference to IEC 61008, the residual current rating has been
increased from 0.5A to 30A – covers both shock & fire protection zone
• Integral / semi integral CBAR – only test as per R 8.2 to R8.7
• Independent CBAR – Sequence test as per Table R.1
• Scope extended to Autoreclosure functionality
• Object extended to temporary fault level like surges
• Definitions related to auto reclosure, voltage dependent method
introduced
• Classification – Method of construction & auto reclosing
57

• Table 1: Standard ratios between Ics and Icu deleted
• Overload current setting definition added
• Ir , Ii , tightening torque , minimum cable cross section to be marked.
• No construction break if 2 pole created from 3 pole by removing center
current path
• No construction break if replacement of trip unit done in one pole in case
of 2 pole and 4 pole variants
• Alternative test programme includes all variants like 1P, 2P, 3P, 4P
• Table 9b and 9c includes additional footnotes
• Dielectric Properties: Higher voltage
• Critical DC load current test
• 21st Harmonics in test waveform
• Higher frequency in test waveform
• Annex A:“Tests” replaced by “consideration of selectivity by desk study”.
• Annex P: DC Circuit breakers for Photovoltaic Applications
• Annex R: Circuit breaker incorporating residual current protection with
auto reclosing functions
58
Summary

• Table 1: Standard ratios between Ics and Icu deleted
- Manufacturer can claim any Ics value
• Markings to be added in existing products
- Ir , Ii , tightening torque , minimum cable cross section
• Critical DC load current
- Need to re-verify claims for DC ratings and certification
- Need to develop pneumatic setup having operating velocity of 0.1 m/s ± 25 %
• For CBs having Ui > 1000V the dielectric properties test voltage will be Ui + 1 200 V a.c.
r.m.s. or 2 Ui
- Need to update testing facility : STL
• Annex A : Needs clarification from IEC
• Annex F and J : 21st Harmonics and Higher frequency test
- Need to update testing facility : STL
- Need to check performance of Electronic releases
• Annex P and Annex R :
- Scope for developing circuit breakers for Photovoltaic and CBAR applications
59
Inputs for Design and STL

Definitions
61
2.5.23
over-current discrimination
co-ordination of the operating characteristics of two or more over-current protective
devices such that, on the incidence of over-currents within stated limits, the device
intended to operate within these limits does so, while the other(s) does (do) not
[441-17-15]
NOTE Distinction is made between
series discrimination involving different over-current protective devices passing
substantially the same over-current and
network discrimination involving identical protective devices passing
different proportions of the over-current.
Replaced with
over-current selectivity
co-ordination of the operating characteristics of two or more over-current
protective devices such that on the incidence of over-currents within stated limits,
the device intended to operate within these limits does so, while the other(s) does
(do) not.

2.21. Overload current setting (Ir)
current setting of an adjustable overload release.
• NOTE In case of a non-adjustable overload release, this value is equal to
nominal current In
• This is done to reduce the ambiguity between In & Ir .
62

• 4.3.5.2.2 Rated service short-circuit breaking capacity (Ics)
The rated service short-circuit breaking capacity of a circuit-breaker is the
value of service short-circuit breaking capacity (see 2.15.2) assigned to
that circuit-breaker by the manufacturer for the corresponding rated
operational voltage, under the conditions specified in 8.3.4. It is expressed
as a value of prospective breaking current, in kA, or as a % of Icu (for
example Ics = 25 % Icu).
Ics shall be at least equal to 25 % of Icu.
• Table 1 (void)
63

Interpretation
• Ics can’t be less than 25% of Icu.
• Guideline for deciding the percentage between Ics & Icu (Table 1) is now
upto manufaturer.
• This will lead to high competition level and dynamics in the market.
• Standardization of Ics & Icu is now out of scope of this standard.
64

5.2 Marking
• Add, at the end of the existing item b), the following two new bulleted
items:
• range of the current setting (Ir) of adjustable overload release (see 4.7.3);
• value or range of the rated instantaneous short-circuit current setting (Ii),
fixed or adjustable (see 4.7.3).
• Add, at the end of the existing item c), the following new bulleted items:
• minimum cable cross-section, if different from Table 9 of IEC 60947-1,
for ratings ≤ 20 A according to rated ultimate short-circuit breaking
capacity Icu;
• values of tightening torque for the circuit-breaker terminals.
65

• Following details also needed to be mentioned on product or in product
catalogue :
• Ir
• conductor size (≤ 20A, if different from TABLE 9)
• Ii ( rated instantaneous short circuit current setting range or value)
• value of tightening torque.
Interpretation
66

7.1.5 List of construction breaks 
• Replace the first dashed item by the following new dashed item:
• – material, finish and dimensions of internal current-carrying parts,
admitting, however, the variations listed in a), b), c), f) and g) below;
f) in the case of the 2-pole and 4-pole variants, replacement of the trip unit
in one pole by a link, to provide an unprotected neutral;
g) creating a 2-pole breaker from a 3-pole breaker by removing the centre
current path.
67

Interpretation
• If any 2-pole breaker is created from 3-pole breaker by removing the
centre current path will not be considered as construction break.
• replacement of the trip unit in one pole by a link in 2-pole and 4-pole
variants will also not be considered as construction break.
68

P. 1. 2 Normative references
IEC 60364 -7-712 , Electrical Installations of buildings - Requirements for
special installations or location - Solar photovoltaic (PV) power supply systems
P.2 Definitions
As a complement to clause 2 of this part of IEC 60947 - 2 the following
definition applies :
P.2.1 Critical load current ( ICRIT)
Value of breaking current, within the range of service conditions, at which the
arcing time is significantly extended [ SOURCE: IEC 60947 - 1, 2.5.16]
P.4 Characteristics of PV circuit – breakers
Clause 4 applies with the following modification:
The impulse withstand voltage (U imp) of PV circuit - breakers shall comply with
Table P. 1.
Annex P – In Detail
69

P.5 Product information
Clause 5.2 applies with the following additions:
A PV circuit - breaker shall have the following information marked under the
conditions of item 5.2 b):
– "PV" or "Photovoltaic", either in the type designation or associated with the rated
characteristics ;
– IEC 60947 - 2 Annex P.
A circuit - breaker rated for use not only on PV installations shall have the PV
ratings clearly separated from the other ratings.
A PV circuit - breaker shall have the following information marked under the
conditions of item 5.2 c):
– method and diagram of series connection of poles as necessary for each rating;
– appropriate connection to the PV generator and load if applicable ;
– appropriate connection to "+" and " - " polarities if applicable;
– thermal current derating for ambient temperatures above 40°C;
– operational characteristics between – 25 °C and + 70 °C.
Annex P – cont..
70

Annex P – cont..
P.6 Normal service, mounting and transport conditions
Clause 6 of this standard applies, with exception of 6.1.1 of IEC 60947 - 1 which is
replaced by the following:
P.6.1 Ambient air temperature
The equipment shall be able to operate in an ambient air temperature from -25
°C up to + 70 °C according to the derating table of thermal current provided by
the manufacturer.
P.7 Constructional and performance requirements
P.7.1 Constructional requirements Subclause 7.1 applies with the following
modifications:
In order to reduce the risk of arcing faults, creepage distances at terminals
between opposite polarities and between live parts and the enclosure or mounting
plate shall meet the values of IEC 60947 - 1 Table 15 multiplied by 1.5. This
requirement does not apply to internal creepage distances. If creepage distances
at terminals are achieved through the use of additional covers, terminal
shields, barriers or equivalent, those additional parts shall be factory mounted on
the product and shall not be removable without a tool. If they are removable,
there shall be a marking on the breaker requiring to re-install them .
71

Annex P – cont..
P.7.2 Performance requirements
Subclause 7.2 applies with the following modifications:
PV circuit - breakers shall be capable of interrupting any current up to their rated
short- circuit breaking capacity, including critical currents, in both forward and
reverse directions. Compliance is checked by the tests of P.8.3.
With reference to 7.2.4.1, such overload conditions do not arise in the case of PV
installations. Overcurrent conditions can only result from a short- circuit.
Therefore, no tests to this clause are required. Tests for short- circuit performance
are given in P.8.3.4 to P. 9 .3.8.
With reference to 7.2.4.2 for operational performance capability, PV circuit-
breakers shall be capable of meeting the requirements of Table P. 2.
Due to the installation rules defined in IEC 60364 -7-712, the risk of a double fault
to earth does not need to be taken in consideration. Therefore, annex H of this
standard is not applicable to PV circuit- breakers.
NOTE The case of a PV circuit - breaker having to interrupt a small fault current on
one pole only is under consideration.
72

Annex P – cont..
P.8.3 Type tests
Subclause 8 .3 applies with the following modifications:
P.8.3.1 Test sequences
With reference to 8.3.1.2, tests omitted from sequence I need not be made if the
PV circuit breaker is derived from an a.c. or d.c. circuit - breaker on which
identical or more severe test have already been conducted, except that tripping
characteristics conducted in a.c. do cover d.c. characteristics.
With reference to 8.3.1.4, alternative test programs do not apply to PV circuit -
breakers.
P.8.3.2 General test conditions
With reference to 8.3.2.1, for all tests, the series connection of poles of the
circuit- breaker shall be in accordance with the manufacturer instructions. The
number of samples to be tested for each test sequence is given in Table 10.
Regardless of marking of connections ("+" or "- " polarities and generator or load),
samples shall be selected and tested according to column "terminals not marked
line/load". With reference to subclause 8.3.2.2.5, the time constant for
operational performance capability, short - circuit tests and critical current test
shall be equal to 1 ms. With reference to subclause 8.3.2.6.4, for 4- pole
circuit- breakers, the additional sequence of operations on the fourth pole and its
adjacent pole is not applicable.
73

Annex P – cont..
P.8.3.3 Test sequence I
Subclause 8.3.3 applies with the following modifications:
With reference to 8.3.3.3.3, for operational performance capability without
current, given in Table P. 2.
With reference to 8.3.3.3.4, for operational performance capability with current,
the number of operating cycles and the number of cycles per hour are given in
Table P. 2 , and the time constant shall comply with P.8.3.2. Regardless of
markings for connections ("+" or " – “polarities and PV generator or load), half of
the operations shall be made with the currents flowing in the forward direction,
the other half with the reverse direction.
In case of circuit - breakers with dependent manual operation, the circuit -
breaker shall be operated with an operating speed, during actuation, of 0,1 m/s ±
25 %, this speed being measured at the extremity when and where the operating
means of the test apparatus touches the actuating means of the circuit - breaker
under test. For rotary knobs the angular velocity shall correspond substantially to
the above conditions, referred to the speed of the operating means (at its
extremities) of the circuit- breaker under test.
With reference to 8.3.3.4, the overload performance test is not applicable.
74

Annex P – cont..
P.8.3.9 Critical load current test
Subclause 8.3.9 applies with the following modifications:
The circuit- breaker shall be closed and opened 10 times on to each of the test
currents, five times with the current flowing in the forward direction, and five times
with the current flowing in the reverse direction. The time constant shall comply
with P.8.3.2.
During the operational performance verification, the breaker shall be subjected to
100 operations instead of 50. This verification need not be made if the critical
current is equal to or greater than the rated current.
P.8.3.10 Thermal cycling test
PV circuit breakers shall to be subjected to temp. cycling according to IEC 60068
-2-14, test Nb, consisting of 50 cycles, each cycle of 1 hour at – 40 °C followed
by 1 hour at + 85°C. Temp. change rate shall be 1 K/min. A higher rate of change
may be used if the temp. measured on the breaker terminals reaches – 37 °C or
+82 °C before the end of the one hour exposure time. At the conclusion of the 50
cycles, the devices shall be returned to room temp. of 25 ± 5 °C for a minimum of 3
hours. The device shall then be subjected to the test of 8.3.3.1.3 followed by a
verification of temp. rise at the main terminals in accordance with 8.3.2.5. The
temp. rise shall not exceed the values given in Table 7.
The no. of samples shall be in accordance of Table10 for Test sequence I.
75

Annex P – cont..
P.8.3.11 Climatic test
PV circuit- breakers shall be subjected to the climatic tests of IEC 60947 -1
Annex Q, category B: environment subject to temperature and humidity,
except that the dry heat test and the low temperature test are not required, as
they are deemed to be covered by the thermal cycling test above.
Product verification during and after the test shall comply with the relevant
requirements of clause 8.5 of this standard.
The number of samples shall be in accordance with the requirements of Table
10 for Test sequence I . At the discretion of the manufacturer, this test may be
combined with the thermal cycling test and made on the same samples.
76

P.3 Classification
Clause 3 applies.
P.7.3 Electromagnetic compatibility (EMC)
Subclause 7.3 applies.
P.8 Tests
P.8.1 Kind of tests
P.8.2 Compliance with constructional requirements
P.8.3.4 Test sequence II
Subclause 8.3.4 applies, with the modifications listed in P.8.3.2.
P.8.3.5 Test sequence III
Subclause 8.3.5 applies with the modifications listed in P.8.3.2.
P.8.3.6 Test sequence IV
P.8.3.7 Test sequence V
P.8.3.8 Test sequence VI
Annex P – cont.. Other clauses
77

4.3.5.2.2 Rated service short-circuit breaking capacity (Ics)
The rated service short-circuit breaking capacity of a circuit-breaker is the value of
service short-circuit breaking capacity (see 2.15.2) assigned to that circuit-breaker
by the manufacturer for the corresponding rated operational voltage, under the
conditions specified in 8.3.4. It is expressed as a value of prospective breaking
current, in kA, corresponding to one of the specified percentages of the rated
ultimate short-circuit breaking capacity, in accordance with Table 1, and rounded up
to the nearest whole number. It may be expressed as a % of Icu (for example Ics = 25
% Icu). Alternatively, when the rated service short-circuit breaking capacity is equal
to the rated short time withstand current (see 4.3.5.4), it may be stated as that
value, in kA, provided that it is not less than the relevant minimum value of Table 1.
Where Icu exceeds 200 kA for utilization category A (see 4.4), or 100 kA for utilization
category B, the manufacturer may declare a value Ics of 50 kA.
78

5.2. Marking
79
IEC 60947-2: 2006-07

5.2 Marking
80
IEC 60947-2: 2006-07

82
Clause Test Test Parameters Conditions check points
Openingundershortcircuit
conditions(8.3.3.1.2) test:
80% In* Short circuit current
setting: Non trip
120% In * short circuit current
setting: Trip
Wait for 3 min.
OpeningunderOverload
conditions(8.3.3.1.2) test:
1.05 *In* Overload current
setting: Non trip
1.3 * In * Overload current
setting: Trip
Wait for 3 min.
After tripping condition,
CBAR shall not reclose
automatically in auto
reclosing mode for 3
mins.
Test of Unwanted
auto-reclosing
R.8.2

83
Cl
au
se
Subc
laus
e Test Test Parameters
Conditions check
points
R.
8.3
Test of auto-reclosing functions by earth leakage faults
R.
8.3.1
Verification of the
correct operation
in the case of
permanent
appearance of
residual current.
can be made on any one pole. 
Fig. R.1. 
After S1 and CBAR being in
closed position , residual
current established by
operating S2 in closed position
for time as defined . 
CBAR shall trip. Also it
should not auto reclose
when S2 is closed.
R.
8.3.2
Verification of the
correct operation
in the case of
temporary
appearance of
residual current.
a.) S1, S2 and CBARs in closed position, the residual
current increased from 20% to 100% of IΔn. within 30
sec.CBAR shall trip. 
S2 should be in ON condition for 1 min. CBAR shall not
auto reclose during this time. 
Residual current decreased by adjustable resistor in
around 30sec, CBAR shall auto reclose.
b) S1 and CBAR being in ON condition, S2 is suddenly
made ON, CBAR shall trip. 
As CBAR trips, residual current decreased by adjusting
resistor R within 30 sec.. CBAR shall auto reclose.
c.) In AR mode, line/control voltage applied, CBAR is
opened manually by operating means.

84
R.8.4
Test of auto-
reclosing
functions by
temporary surges
Test conditions & test set
up as per B.8.12.1.5
Criteria A: During test,
CBAR shall not trip.After
test, R.8.3.2.b)  
Criteria B: During test
tripping is allowed, After
test when no surges will
be there, CBAR shall
auto reclose.
Verification of the isolating function
Claus
e Subclause Test Test Parameters
Conditions check
points
R.8.5
R. 8.5.1
Leakage current
between open
contacts
Value of leakage current measured through each
pole with the contacts in open position same as that
of each test sequences.
R. 8.5.2
Impulse voltage
between open
contacts
During Test of dielectric properties , test voltage
applied between line terminals connected together
and load terminals connected together, with contacts
in open position. Test voltage as per Table 14.
R. 8.6
Verification of
residual short
circuit making
and breaking
capacity
B. 8.10 applies.

85
Claus
e
Subclau
se Test Test Parameters
Conditions check
points
R. 8.7
Verification of the effects of
environmental conditions for
auto recolosing functions
a) After test seq.II, R.8.3.2 b) 
b) After test seq. III, R. 8.3.2 b) 
c) After test seq. B.1, operating characteristics, R.8.3.2
b) 
d) After test seq. B.2, rated short circuit making and
breaking capacity, R.8.3.2 b) 
e) After test seq. B.3, effects of environmental
conditions, R.8.3.2 b) 
f) After test sequence B.4, EMC, R.8.3.2 b)

8.3.1.4 ( Amendment 1)
8.3.1.4 Alternative test programme for circuit breakers having both three pole
and four pole variants
• These alternative test programmes may be applied when there is no construction
break
( see 7.1.5) between the poles of the four pole variant and the poles of the three
pole variant.
Compliance with the test requirements may be met by carrying out one of the
alternative programmes 1 or 2 below.

• Programme 1: Table 9 : 3 Pole variant Programme 2: Table 9 : 4
Pole variant
Table 9b : 4 Pole variant Table 9c : 3
Pole variant

86

87
8.3.1.4 ( Amendment 2)
8.3.1.4 Alternative test programmes for circuit-breakers of a given frame size
and
design having a different number of poles
• These alternative test programmes may only be applied when all ratings are the
same or lower than the variant submitted to the full programme of Table 9,
and construction breaks are the same for all variants. In the case of 1-pole
circuit-breakers the voltage ratings shall be equal to or lower than the line-to
neutral voltage of the variant tested to Table 9. A 2-pole circuit-breaker
produced by removing the centre current path from a 3-pole circuit-breaker
tested to Programme 1 or Programme 2 of this clause need not be tested as it is
considered to be covered by the tests on the 3-pole variant.
• Programme 1: Table 9 : on 3 pole variant. Programme 2: Table 9 : on 4
pole variant.
In addition, Table 9b : on other variants. In addition, Table 9c : on
other variants.

Footnotes of Table 9b
Note c : One sample of maximum current rating only, tested at max kVA rating
(Icu × corresponding Ue).
Implications: Rated ultimate short-circuit breaking capacity test , Icu needed to be done
only on maximum current rating, tested at max kVA rating ( Icu * corresponding Ue).
Note d : Without verification tests of items c) (undervoltage releases) and
d) (shunt releases).
Implications : For test sequence I, Subclause: 8.3.3.2: Construction and mechanical
operation,
No need to verify under voltage and shunt releases for 1,2 or 4 pole variants.
Note e : Applicable only to 1-pole variant; not required for 2-poles variants
Implications : For test sequence I, Subclause 8.3.3.1.2 : Short circuit releases and
Subclause 8.3.3.1.3 : Overload release, no need of any verification on
2 pole variants.
Note f : In case of 4-poles devices with different levels of neutral protection (e.g. 60
% or 100 %), only the variant with the highest level has to be tested according to
Table 9b.
Implications : For applicability to 4 pole variants, which means if the neutral current
vary from 60 % to 100%, then all the sequence test has to be done at highest level. 92

Note g: One sample of maximum current rating only, for each test sequence.
Implications: For 1P or 2P variants of circuit breaker , only one sample of maximum
rating has to be tested at each sequence.
Note h: One sample of maximum current rating for each test sequence; in the
case of one or more construction breaks (see 2.1.2 and 7.1.5) within the
frame size, a further sample is tested at the maximum rated current
corresponding to each construction.
Implications : For 4 Pole variants, normally test is done on one sample at max
rating. However, in case of construction breaks, then one more sample with
maximum rating has to be tested for all test sequences.
Note j : This test is not required for electronic trip units.
Implications : For sequence I, subclause 8.3.3.1.3 : Overload release : test is not
required for electronic trip units.
93
Footnotes of Table 9b

Note a : Vacant.
Note b: This test sequence also applies when, for the 4-poles testing, Sequence III on
the 4-poles variant is replaced by Sequence II or Sequence VI (see Table 9)
Implications: This foot note is same as that of Amend 1 . Table 9c is for 3P variants. This
note is about 4P variants.
Note c : One sample of maximum current rating only, tested at max kVA rating
(Icu × corresponding Ue).
Implications: Rated ultimate short-circuit breaking capacity test , Icu needed to be done
only on maximum current rating, tested at max kVA rating ( Icu * corresponding Ue).
Note d: Without verification tests of items c) (undervoltage releases) and d) (shunt
releases).
Implications: Though present in Table 9c, does not relate to any of the clause.
Note e : Applicable only to 1-pole variant; not required for 2-poles variants
Implications : For test sequence I, Subclause 8.3.3.1.2 : Short circuit releases and
Subclause 8.3.3.1.3 : Overload release, no need of any verification on
2 pole variants.
97
Footnotes of Table 9c

Note f: Vacant
Note g: One sample of maximum current rating only, for each test sequence.
Implications: For 1P or 2P or 3P variants of circuit breaker , only one sample of
maximum rating has to be tested at each sequence.
Note h : Vacant
Note j : This test is not required for electronic trip units.
Implications : For sequence I, subclause 8.3.3.1.3 : Overload release : test is not
required for electronic trip units.
98
Footnotes of Table 9c

Annex A  
• The word DISCRIMINATION is replaced by SELECTIVITY throughout annexure .
• Delete "(or Ics)“ in each of the below list.
- A.3.1 in the first paragraph;
- new A.5.1 in the first paragraph;
- A.6.2 b) in the second paragraph;
- A.6.3 in the sixth & eighth paragraphs;
- Figure A.2/A.3.
A.5.1-Discrimination may be partial (see Figure A.4) or total up to the rated short-
circuit breaking capacity Icu (or Ics) of C1.
Selectivity may be partial (see Figure A.4) or total up to the rated short-circuit
breaking capacity Icu of C1.
Replace with

Annex – A…
• The following two sub-clauses were added :
- A.5.2 Tests for verification of selectivity between circuit-breakers.
(O-t- CO with C1 at max and C2 at min time and current settings)
- A.5.3 Results to be obtained.
• Fig. A.7 : Test circuit for verification of selectivity added.
• Under Figure A.7
Replace "W2, W3 = 75 cm…" to "W2 +W3 = 75 cm…“
Remove the line "W3 = 25 cm…”
• Adding Note1, 2, 3 and 4 of Figure A.6 to A.7.

Annex- B Circuit-breakers incorporating residual  
current protection
• B.8.1.2 Additional test sequences
• Below Paragraph added after table B.4
For CBRs having variants with different number of poles, tests shall be made on the
variant with the greatest number of poles. For a variant where there is no
construction break from the tested variant, no additional tests are required. If
the variants construction is not identical to the variant tested then those variants
shall also be tested.
102

Annex L- Circuit-breakers not fulfilling the
requirements for over-current protection
L.1 Scope
This annex covers circuit-breakers which do not fulfill the requirements for over-current
protection specified in the main part of this standard, hereinafter referred as CBIs. They
are capable of being tripped by an auxiliary device, e.g. shunt or under voltage release.
They do not provide circuit protection1) but may trip under short-circuit conditions for self-
protection. They have a conditional short-circuit rating and may be used for isolation.
They may incorporate accessories such as auxiliary and alarm switches for control
purposes, and/or remote operators.
L.7.2.1 General
Add, at the end of the existing text , the following new paragraph:
For CBIs having variants with different number of poles, tests shall be carried out
on each variant.
Changed as
103

Annex M- Modular residual current devices
(without integral current breaking device)
M.8.1.1 Type tests
Add, after the existing Table M.3 and before the existing text below Table
M.3 , the following new paragraph:
For terminal - type MRCDs having variants with different number of poles, tests shall
be made on the variant with the greatest number of poles. For a variant where
there is no construction break from the tested variant, no additional tests are required.
If the variants construction is not identical to the variant tested then those variants shall
also be tested.
104

Annex O
Instantaneous trip circuit-breakers (ICB)
Add , at the end of the existing text, the following new paragraph:
For ICBs having variants with different number of poles, tests shall be made on the variant
with the greatest number of poles. The other variant (s) shall be submitted to the tests
of sequence III only (without the verification of overload releases).
O.6.1.2 Test sequences
Tests shall be made according to sequences II and III of this standard without the
verification of overload releases.
Added
105

Annex C Individual pole short-circuit test sequence
C.2 Test of individual pole short- circuit breaking capacity
The applied voltage shall be phase-to-phase voltage corresponding to the
maximum rated operational voltage of the circuit-breaker at which it is suitable
for application on phase-earthed systems.
Replace the first sentence of the existing second paragraph by the following
new sentence:
The test voltage shall be the phase - to - phase voltage corresponding to the
for application on phase -earthed systems, taking into account the requirements
for recovery voltage of 8.3.2.2.6.
Replace with
106

H.2 Individual pole short circuit
The applied voltage shall be the phase-to-phase voltage corresponding to the
for application on IT systems.
Replace with
Replace the first sentence of the second existing paragraph by the following
new sentence:
The test voltage shall be the phase - to - phase voltage corresponding to the
maximum rated operational voltage of the circuit - breaker at which it is
suitable for application on IT systems, taking into account the requirements for
recovery voltage of 8.3.2.2.6 .
Annex H :Test sequence for circuit-breakers for IT
systems
107

Annex E- Items subject to agreement between
manufacturer and user
In the existing table, replace "8.3.2.6.4" of the 5th line by "8.3.2.6.4.3" .
In the existing table, replace "8.3.4 .4 " of the ninth line by "8.3.4.5".
In the existing table, insert the following new eleventh line:
8.5 Special tests – Damp heat, salt mist, vibration and shock
Delete the last existing line "F.4.1.3 ..." of the table.
Changed as / correction of error
108

Annex K
Annex K- Glossary of symbols related to products
covered by this standard
Replace in the existing Figure K.1, introduced by Amendment 1,"IR" by "Ir" and
"tR" by "tr“.
109
• Rated voltage of the voltage source of an MRCD - Us
• Rated voltage of the monitored circuit for an MRCD - Un
• Rated residual short time withstand current of an MRCD - I∆w
• Rated conditional short circuit current - Icc
• Rated conditional residual SC current of an MRCD - I∆c
• MRCD’s of type B which is for AC/DC and pulsed dc
• Test device CBR or MRCD - T
MRCD: Modular residual current devices (without integral current
breaking device)
CBR: circuit breaker providing residual current protection
New symbols have been added :

Definitions added in Annex R
R.2.1 auto-reclosing
• automatic-reclosing
operating sequence of a mechanical switching device whereby, following its opening,
it closes automatically depending on the specific conditions
R.2.2 auto-reclosing operating residual current (IΔar)
value of the residual current at which (and below which) CBAR recloses automatically
under the specified conditions
R.2.3 intermittent monitoring voltage
voltage outputted to loads from CBARs to monitor earth leakage faults, which is
generated
with a constant time interval for a constant period of time
R.2.4 continuous monitoring voltage
voltage outputted to loads from CBARs to monitor earth leakage faults, which is
generated continuously
112

Classification in Annex R
R.3.1 According to the method of construction
R.3.1.1 Integral type (circuit-breakers)
CBARs as one a single unit comprising an auto-reclosing function unit (for example, PCB, etc) integrated
by the manufacturer with circuit-breakers.
R.3.1.2 Semi-integral type (circuit-breakers)
CBARs, internal circuits or components including the wire within which are affected (i.e. modified) by
the mutual connections between circuit-breakers and auto-reclosing device for interfacing the
control signal or measuring signal, regardless of the methods assembled into common or separate
external enclosure.
R.3.1.3 Independent type (auto-reclosing) (devices)
A series of auto-reclosing devices independently (i.e. externally) connected without the modification of
internal circuits or components of the circuit-breakers.
NOTE This kind of device is not produced as being assembled with a circuit-breaker. When it is used in connection with the
circuit-breaker, however, the assembled product itself maintains the same purpose as the CBAR stated in this annex.
Therefore, independent type auto-reclosing devices shall comply with the scope and requirements of this annex.
R.3.2 According to the method of auto-reclosing
R.3.2.1 Time delay (or time-dependent) type TD
CBAR or ARD in which the auto-reclosing takes place after a time-delay without consideration of the
circuit conditions. The number of consecutive reclosing operations is limited (e.g. three operations).
R.3.2.2 Earth leakage monitoring type M
CBAR or ARD which monitors the earth leakage current in the circuit and does not allow reclosure if or
where the earth leakage current exceeds IΔar 113

Design Requirements
114
R.7.1 Design requirements
As a complement to Clause 7.1 and Annex B.7.1 of this standard, the following additional requirements shall
apply:
R.7.1.1 Mode selection
Both auto-reclosing (mode) and manual-reclosing (mode) shall be equipped together with a select switch to
choose either of the two functions.
NOTE It means that in some cases, it is necessary for the operator to disable the auto-reclosing functions for
purposes of surveillance inspection, routine testing, etc.
Compliance is checked by inspection and by the clause of R.5.
R.7.1.2 Indication lamps
Indication lamps (for example, normal operation mode, auto-reclosing standby mode, if applicable, burnout state
of built-in fuse, etc) shall be equipped clearly visible with CBARs after the installation.
Compliance is checked by inspection and during the tests of the relevant clause.
R.7.1.3 CBARs using line voltage
In case of using line voltage in order to monitor the earth leakage faults on load, the built-in protection devices
(fuse, etc.) shall be connected to the relevant circuits for safety. Also those kinds of protection devices shall
have the product certificate or test report for their functions, which the manufacturer should submit.
NOTE 1 However, protection devices have no need to be removable or replaceable.
When the relevant circuit is connected to every pole on the line side of CBARs, each pole shall be all equipped
with protection devices.
NOTE 2 Current limiting devices or safety isolating transformers are not regarded as protection devices.
Moreover, for the burnout of the protection devices (fuse, etc.), the method of indicating the burnout (for
example lamps) shall be mounted on the front side of CBARs. In the absence of such indication methods,
CBARs shall not be reclosed even manually by operating means in the burnout state of protection devices.
Compliance is checked by inspection and by the circuit diagrams, parts list, certificate, test report, which the
manufacturer should submit.
R.7.1.4 CBARs using batteries
In case of using batteries in order to monitor the earth leakage faults on load, those batteries shall have the
product certificate, or test report for their functions, which the manufacturer should submit.

Rated values
B.4.1.1 Rated residual operating current (IΔn)
The r.m.s. value of a sinusoidal residual operating current (see B.2.2.4) assigned to the CBR by
the manufacturer, at which the CBR shall operate under specified conditions.
NOTE For a CBR with multiple settings of residual operating current, the highest setting is used to
designate its rating. See, however, Clause B.5 concerning marking.
B.4.2.1 Preferred values of rated residual operating current (IΔn)
Preferred values of rated residual operating current are
0,006 A – 0,01 A – 0,03 A – 0,1 A – 0,3 A – 0,5 A – 1 A – 3 A – 10 A – 30 A
Higher values may be required.
IΔn may be expressed as a percentage of the rated current.
B.4.1.2 Rated residual non-operating current (IΔno)
The r.m.s. value of sinusoidal residual non-operating current (see B.2.2.5) assigned to the CBR
• by the manufacturer at which the CBR does not operate under specified conditions.
B.4.2.2 Minimum value of rated residual non-operating current (IΔno)
The minimum value of rated residual non-operating current is 0.5 IΔn.
115

B.8.10
116
B.8.10 Verification of the residual short-circuit making and breaking capacity
This test is intended to verify the ability of the CBR to make, to carry for a specified time and to break
residual short-circuit currents.
B.8.10.1 Test conditions
The CBR shall be tested according to the general test conditions specified in 8.3.2.6, using Figure 9 of IEC
60947-1, but connected in such a manner that the short-circuit current is a residual current.
The test is carried out at phase to neutral voltage on one pole only which shall not be the neutral pole..
Where applicable, the CBR is adjusted at the lowest setting of residual operating current and at the maximum
setting of time-delay.
B.8.10.2 Test procedure
The sequence of operations to be performed is
O – t – CO
B.8.10.3 Conditions of the CBR after test
B.8.10.3.1 Following the test of B.8.10.2 the CBR shall show no damage likely to impair its
further use and shall be capable, without maintenance, of
– withstanding a voltage equal to twice its maximum rated operational voltage, under the conditions of
8.3.3.4.1 item 4) of IEC 60947-1. For the purposes of this standard, circuits incorporating solid-state devices
shall be disconnected for the tests;
– making and breaking its rated current at its maximum rated operational voltage.
B.8.10.3.2 The CBR shall be capable of performing satisfactorily the tests specified in
B.8.2.4.3, but at a value of 1,25 IΔn and without measurement of break time. The test is made on any one
pole, taken at random. If the CBR has an adjustable residual operating current, the test is made at the lowest
setting, at a current of a value of 1,25 times that setting.

ABB – S800 PV Circuit connection for high voltage
120

IEC 60947-2 Guide for Low-Voltage Circuit Breakers

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