IEC 60755-1:2022

General safety requirements for residual current operated protective devices - Part 1: Residual current operated protective devices for DC systems

IEC 60755-1:2022 gives requirements, recommendations and information for the drafting of standards for residual current operated protective devices, intended to be used in DC systems, hereafter referred to as DC-RCDs.
This group safety publication is primarily intended for use by technical committees in the preparation of standards in accordance with the principles laid down in IEC Guide 104 and lSO/lEC Guide 51. It is not intended for use by manufacturers or certification bodies.

General Information

• Status: Published
• Publication Date: 23-Oct-2022
• ICS: 29.120.50 - Fuses and other overcurrent protection devices
• Technical Committee: SC 23E - Circuit-breakers and similar equipment for household use
• Drafting Committee: WG 2 - TC 23/SC 23E/WG 2
• Current Stage: PPUB - Publication issued
• Start Date: 18-Nov-2022
• Completion Date: 24-Oct-2022

Standards Content (Sample)

IEC 60755-1
®

Edition 1.0 2022-10
INTERNATIONAL
STANDARD

GROUP SAFETY PUBLICATION

General safety requirements for residual current operated protected devices –
Part 1: Residual current operated protective devices for DC systems

IEC 60755-1:2022-10(en)

---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
Copyright © 2022 IEC, Geneva, Switzerland

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.


IEC Secretariat Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland

About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always have
committee, …). It also gives information on projects, replaced access to up to date content tailored to your needs.
and withdrawn publications.

Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 300 terminological entries in English
details all new publications released. Available online and once
and French, with equivalent terms in 19 additional languages.
a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc

If you wish to give us your feedback on this publication or need
further assistance, please contact the Customer Service
Centre: [e-mail].

---------------------- Page: 2 ----------------------
IEC 60755-1

®


Edition 1.0 2022-10




INTERNATIONAL



STANDARD













GROUP SAFETY PUBLICATION





General safety requirements for residual current operated protected devices –

Part 1: Residual current operated protective devices for DC systems


























INTERNATIONAL

ELECTROTECHNICAL


COMMISSION





ICS 29.120.50 ISBN 978-2-8322-5867-5




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


® Registered trademark of the International Electrotechnical Commission

---------------------- Page: 3 ----------------------
– 2 – IEC 60755-1:2022 © IEC 2022
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 7
3 Terms and definitions . 7
4 Classification . 9
5 Characteristics of residual current devices . 9
6 Marking and other product information . 12
7 Conditions for operation in service and for installation . 12
8 Requirements for construction and operation . 12
9 Tests . 15
Annex A (informative) Recommended diagram for short-circuit tests . 29
Bibliography . 32

Figure 118 – Example of test circuit for verification of ageing of electronic components . 27
Figure 200 – Examples of installation. 28
Figure A.101 – Diagram for all the short-circuit tests . 30

Table 100 – Example for values of rated operational voltage (U ) . 22
e
Table 101 – Values of influencing quantities . 22
Table 102 – Marking for DC-RCDs according to 4.15.1 . 23
Table 103 – Marking for DC-RCDs according to 4.15.2 and 4.15.3 . 24
Table 104 – Standard values of maximum break time for non-time-delay DC-RCDs . 24
Table 108 – Standard values of break time and non-actuating time for time-delay
DC‑RCDs . 25
Table 113 – Tripping current limits . 25
Table 130 – Withstand values and duration of temporary overvoltages . 25
Table 145 – Immunity tests . 26
Table 146 – Voltage dips and short interruptions levels . 26

---------------------- Page: 4 ----------------------
IEC 60755-1:2022 © IEC 2022 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

GENERAL SAFETY REQUIREMENTS FOR RESIDUAL
CURRENT OPERATED PROTECTED DEVICES –

Part 1: Residual current operated protective devices for DC systems

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 60755-1 has been prepared by subcommittee 23E: Circuit breakers and similar equipment
for household use, of IEC technical committee 23: Electrical accessories. It is an International
Standard.
This document is intended to be used in conjunction with IEC 60755.
The text of this International Standard is based on the following documents:
Draft Report on voting
23E/1273/FDIS 23E/1299/RVD

Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.

---------------------- Page: 5 ----------------------
– 4 – IEC 60755-1:2022 © IEC 2022
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 60755 series, published under the general title General safety
requirements for residual current operated protected devices, can be found on the IEC website.
This International Standard is to be used in conjunction with IEC 60755:2017.
The following differing practices of a less permanent nature exist in the countries indicated
below:
– IEC 60755:2017, IEC 60755:2017, 5.3.1.12: 1 000 A, 2 000 A, 2 500 A, 7 500 A and 9 000 A
are also considered preferred values (Korea and Japan);
– IEC 60755:2017, IEC 60755:2017, 8.1.1: multiple settings are not allowed (Australia,
Germany, Denmark, the UK and Switzerland);
– IEC 60755:2017, IEC 60755:2017, 8.1.2: the colours red and green are not used for contact
position indication (US).
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

---------------------- Page: 6 ----------------------
IEC 60755-1:2022 © IEC 2022 – 5 –
INTRODUCTION
Residual current devices are used for protection against electric shocks.
In IEC 60364 (all parts), residual current devices are used for automatic disconnection of supply
in case of fault (see Clause 411 of IEC 60364-4-41:2005+AMD1:2017) and residual current
devices with rated residual operating current not exceeding 30 mA are used as additional
protection (see Clause 415 of IEC 60364-4-41:2005+AMD1:2017). The IEC has developed a
set of standards for residual current operated protective devices intended to be used in AC
systems.
DC systems are used for applications such as photovoltaic installations, data and telecom
centres and electric vehicle charging systems. In addition, standards for plugs and socket-
outlets for ICT equipment installed in data centres and telecom centres have been published.
Residual current devices for DC systems are used to provide fault protection and/or additional
protection (according to IEC 60364-4-41:2005 and IEC 60364-4-41:2005/AMD1:2017).
This document defines the operating characteristics for residual current operated protective
devices for DC systems. Details of how they should be installed to provide the desired level of
protection are specified in the various parts of the IEC 60364 series. The operating
characteristics given in this document are based on the information contained in IEC 60479 (all
parts).
This document has been prepared as a Group Safety Publication by subcommittee 23E in
accordance with its Group Safety Function for residual current devices. It is intended for use by
technical committees in the preparation of standards for residual current unit, function or
devices when it is intended to provide protective measures according to IEC 60364 (all parts).
It is not intended for use as a stand-alone document, for example, for certification.
This document is intended for use in conjunction with IEC 60755. Where a particular subclause
of IEC 60755 is not mentioned in this Part 1, that subclause applies as far as is reasonable.
Where this Part 1 states "addition", "deletion" or "replacement", the corresponding requirement,
test specification or explanatory material in IEC 60755 should be adapted accordingly.

---------------------- Page: 7 ----------------------
– 6 – IEC 60755-1:2022 © IEC 2022
GENERAL SAFETY REQUIREMENTS FOR RESIDUAL
CURRENT OPERATED PROTECTED DEVICES –

Part 1: Residual current operated protective devices for DC systems



Replacement of Clause 1 of IEC 60755:2017 by:
1 Scope
This document gives requirements, recommendations and information for the drafting of
standards for residual current operated protective devices, intended to be used in DC systems,
hereafter referred to as DC-RCDs.
NOTE 1 When referring to IEC 60755, "RCD" shall be understood as "DC-RCD".
This document is primarily intended to be used as a reference for drafting product safety
standards for:
– DC-RCD intended for general use;
– DC-RCD specifically intended to be incorporated in a specific item of equipment;
– DC-RCD embedded in an equipment.
This document is applicable for standards covering devices:
– which detect a residual current,
– compare it to a reference value, and
– open the contacts when the residual current exceeds this reference value.
Any association of devices, each one of them performing separately one or two of the above-
mentioned functions but acting together in order to accomplish all three functions, is also
covered by this document.
DC-RCDs are intended to provide fault protection, the exposed conductive parts of the
installation being connected to a protective conductor, in accordance with IEC 60364-4-41:2005
and IEC 60364-4-41:2005/AMD1/2017.
DC-RCDs having a rated residual operating direct current not exceeding 80 mA and having a
rated voltage not exceeding 220 V DC for single-pole or 440 V DC for two-pole are also used
as a provision for additional protection, according to IEC 60364-4-41.
NOTE 2 Further requirements for higher voltages are under consideration.
NOTE 3 The value of 80 mA was the result of a calculation based on the content of clause 6 of IEC 60479-1:2018
and 5.3.4 of IEC 60479-2:2019.
NOTE 4 In Austria the value of 80 mA is considered as provisional until a broader and more solid set of data than
the actual basis of the IEC 60479 series is available for DC.
In accordance with IEC 60364-4-42, residual current devices with a rated residual operating
current not exceeding 300 mA can also be used to provide protection against fire hazards due
to insulation faults.
DC-RCDs are suitable for isolation. They are suitable for use in TN, TT, and, under specific
conditions, IT systems.

---------------------- Page: 8 ----------------------
IEC 60755-1:2022 © IEC 2022 – 7 –
DC-RCDs are resistant to unwanted tripping including the case where surge voltages (as a
result of switching transients or induced by lightning) cause loading currents in the installation
without occurrence of flashover.
This group safety publication is primarily intended for use by technical committees in the
preparation of standards in accordance with the principles laid down in IEC Guide 104 and
lSO/lEC Guide 51. It is not intended for use by manufacturers or certification bodies.
One of the responsibilities of a technical committee is, wherever applicable, to make use of
group safety publications in the preparation of its publications. The requirements, test methods
or test conditions of this group safety publication will not apply unless specifically referred to or
included in the relevant publications.
2 Normative references
Clause 2 of IEC 60755:2017 is applicable except as follows:
Addition:
IEC 61000-4-2, Electromagnetic compatibility (EMC) – Part 4-2: Testing and measurement
techniques – Electrostatic discharge immunity test
IEC 61000-4-3, Electromagnetic compatibility (EMC) – Part 4-3: Testing and measurement
techniques – Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-4, Electromagnetic compatibility (EMC) – Part 4-4: Testing and measurement
techniques – Electrical fast transient/burst immunity test
IEC 61000-4-5, Electromagnetic compatibility (EMC) – Part 4-5: Testing and measurement
techniques – Surge immunity test
IEC 61000-4-6, Electromagnetic compatibility (EMC) – Part 4-6: Testing and measurement
techniques – Immunity to conducted disturbances, induced by radio-frequency fields
IEC 61000-4-16, Electromagnetic compatibility (EMC) – Part 4-16: Testing and measurement
techniques – Test for immunity to conducted, common mode disturbances in the frequency
range 0 Hz to 150 kHz
IEC 61000-4-17, Electromagnetic compatibility (EMC) – Part 4-17: Testing and measurement
techniques – Ripple on d.c. input power port immunity test
IEC 61000-4-29, Electromagnetic compatibility (EMC) – Part 4-29: Testing and measurement
techniques – Voltage dips, short interruptions and voltage variations on d.c. input power port
immunity tests
IEC 61543:2022, Residual current-operated protective devices (RCDs) for household and
similar use – Electromagnetic compatibility
3 Terms and definitions
Clause 3 of IEC 60755:2017 is applicable except as follows:
Addition:

---------------------- Page: 9 ----------------------
– 8 – IEC 60755-1:2022 © IEC 2022
3.101
residual operating direct current
value of residual direct current which causes the DC residual current device to operate under
specified conditions
[SOURCE: IEC 60050-442:2019, 442-05-72]
3.102
residual non-operating direct current
value of residual direct current at and below which the DC residual current device does not
operate under specified conditions
[SOURCE: IEC 60050-442:2019, 442-05-73]
3.103
residual direct current making and breaking capacity
value of a residual prospective direct current which a DC residual current device can make,
carry for its opening time and break under specified conditions of use and behaviour
[SOURCE: IEC 60050-442:2019, 442-05-74, modified]
3.104
conditional direct short-circuit current
value of a prospective direct current, which a DC residual current device without integral short-
circuit protection, but protected by a short-circuit protective device in series, can withstand
under specified conditions of use and behaviour
[SOURCE: IEC 60050-442:2019, 442-05-75]
3.105
conditional residual direct short-circuit current
value of a residual direct prospective current, which a DC residual current device without
integral short-circuit protection, but protected by a short-circuit protective device in series, can
withstand under specified conditions of use and behaviour
[SOURCE: IEC 60050-442;2019, 442-05-76, modified]
3.106
mid-point
common point between two symmetrical circuit elements the opposite ends of which are
electrically connected to different line conductors of the same circuit
[SOURCE: IEC 60050-195:1998, 195-02-04]
3.107
M-pole
part of a DC-RCD associated exclusively with one electrically separated conducting path
intended to connect and to disconnect the mid-point
3.108
time constant
rise time T = L/R (ms) of a prospective direct current to reach a value of 0,632 times the
maximum peak current

---------------------- Page: 10 ----------------------
IEC 60755-1:2022 © IEC 2022 – 9 –
3.109
rated direct making and breaking capacity
I
m
value of a prospective direct current, which a DC residual current device is capable of making
and breaking at a stated voltage under specified conditions of use and behaviour
4 Classification
Clause 4 of IEC 60755:2017 is applicable except as follows:
Deletion of Subclause 4.4.
4.10 According to the number of poles and current paths
Subclause 4.10 of IEC 60755:2017 is applicable except as follows:
Replacement of notes to 4.10.1 and 4.10.3:
NOTE In this case, the M-path does not contain any switching contact.
Deletion of 4.10.5 and 4.10.6.
4.15 According to the intended use
Deletion in note 1:
e.g. IEC 61008-1
Addition:
4.101 According to the current direction through the poles
4.101.1 Polarised DC-RCD
4.101.2 Non-polarised DC-RCD
5 Characteristics of residual current devices
5.1 Summary of characteristics
Subclause 5.1 of IEC 60755:2017 is applicable except as follows:
Deletion of the third dash.
Replacement of the fourth, fifth, sixth and seventh dashes:
– rated direct making and breaking capacity I (see 5.2.4);
m
– rated residual operating direct current I (see 5.2.5);
Δn
– rated residual non-operating direct current I (see 5.2.6);
Δno
– rated residual direct making and breaking capacity I (see 5.2.7);
Δm
Replacement of the ninth, tenth and eleventh dashes:
– operating characteristics (see 5.2.10)
– rated conditional short-circuit direct current I (see 5.2.8);
nc

---------------------- Page: 11 ----------------------
– 10 – IEC 60755-1:2022 © IEC 2022
– rated conditional residual short-circuit direct current I (see 5.2.9);
Δc

Wherever in IEC 60755, it is referred to
– rated making and breaking capacity I
m
– rated residual operating current I
Δn
– rated residual non-operating current I
Δno

– rated residual making and breaking capacity I
Δm
– rated conditional short-circuit current Inc
– rated conditional residual short-circuit current I
Δc

It should be read as:
– rated direct making and breaking capacity I ;
m
– rated residual operating direct current I ;
Δn
– rated residual non-operating direct current I ;
Δno
– rated residual direct making and breaking capacity I ;
Δm
– rated conditional short-circuit direct current I ;
nc
– rated conditional residual short-circuit direct current I ;
Δc
5.2 Rated quantities and other characteristics
Subclause 5.2 of IEC 60755:2017 is applicable except as follows:
Deletion of 5.2.3.
Replacement in 5.2.4, 5.2.7, 5.2.8 and 5.2.9:
"RMS value of the AC component" by "value of the prospective direct current"
Replacement of 5.2.10:
5.2.10 Operating characteristics
DC-RCD ensures tripping for residual smooth direct currents, whether suddenly applied or
slowly rising, independent of polarity.
Addition:
5.2.101 Time-delay DC-RCD
Time-delay DC-RCD which complies with the relevant part of Table 108 if applicable.
5.3 Standard and preferred values
Clause 5.3 of IEC 60755:2017 is applicable except as follows:
Addition:
All rated values shall be read as DC values.

---------------------- Page: 12 ----------------------
IEC 60755-1:2022 © IEC 2022 – 11 –
Replacement of 5.3.1 by:
5.3.1 Values of rated operational voltage (U )
e
The values of rated operational voltage shall be defined in the relevant product standard.
Examples are given in Table 100.
Replacement of 5.3.3 by:
5.3.3 Standard values of rated residual operating direct current (I )
Δn
Standard values of rated residual operating direct current are:
0,02 A – 0,08 A – 0,3 A – 0,6 A – 1 A – 2 A – 3 A – 5 A – 10 A – 20 A – 30 A
NOTE 1 The value of 80 mA was the result of a calculation based on the content of 5.3.4 of IEC TS 60479-2:2017.
NOTE 2 In Austria the value of 80 mA is considered as provisional until a broader and more solid set of data than
the actual basis of the IEC 60479 series is available for DC.
5.3.4 Standard value of residual non-operating current (I )
Δno
Subclause 5.3.4 of IEC 60755:2017 is applicable except as follows:
Removal of the note.
Removal of 5.3.5.
5.3.7 Standard values of operating time
Replacement of 5.3.7.1:
5.3.7.1 Standard values of maximum break time for non-time delay DC-RCDs
Standard values of maximum break time for non time-delay type DC-RCDs are given in
Table 104.
5.3.7.2 Standard values of actuating and non-actuating times for time-delay type
residual current devices
Subclause 5.3.7.2 of IEC 60755:2017 is applicable except as follows:
Replacement of fourth paragraph:
Time-delay type DC-RCDs are permitted only for I higher than 0,08 A.
Δn
Replacement of fifth paragraph:
Standard values of actuating and non-actuating times for time-delay type DC-RCDs are given
in Table 108.
5.3.9 Standard minimum value of non-operating overcurrent in case of a single phase
load through a three- or four-pole or four-current-paths RCD
Replacement of 5.3.9:

---------------------- Page: 13 ----------------------
– 12 – IEC 60755-1:2022 © IEC 2022
5.3.9 Standard minimum value of non-operating overcurrent in case of a single phase
load through a three-pole DC-RCD or a DC-RCD with three current paths
The standard minimum value of non-operating overcurrent in case of a single-phase load
through a three-pole DC-RCD or a DC-RCD with three-current-paths shall be defined in the
relevant product standard.
NOTE For DC-RCDs with integral overcurrent protection, this minimum value can be lower, depending on the
characteristics of the overcurrent protection.
5.3.10 Minimum value of the rated making and breaking capacity (I )
m
Subclause 5.3.10 of IEC 60755:2017 is applicable except as follows:
Deletion of third paragraph.
5.3.11 Minimum value of the rated residual making and breaking capacity (I )
Δm
Subclause 5.3.11 of IEC 60755:2017 is applicable except as follows:
Deletion of third paragraph.
6 Marking and other product information
6.1 Information and marking for DC-RCDs according to 4.15.1
Subclause 6.1 of IEC 60755:2017 is applicable except as follows:
Replacement of first paragraph:
The information given in column 2 of Table 102 shall be provided. The position of marking shall
be specified in the relevant product standard (e.g. visible after installation, on the product, in
the leaflet or manufacturer’s catalogue).
Deletion of last paragraph.
6.2 Information and marking for RCDs according to 4.15.2 and 4.15.3
Subclause 6.2 of IEC 60755:2017 is applicable except as follows:
Replacement of Table 3 by Table 103.
7 Conditions for operation in service and for installation
7.1 Preferred ranges of application, reference values of influencing quantities/factors
and the associated test tolerances
Subclause 7.1 of IEC 60755:2017 is applicable except as follows:
Replacement of Table 1 by Table 101.
8 Requirements for construction and operation
8.1.2 Mechanism
Subclause 8.1.2 of IEC 60755:2017 is applicable except as follows:

---------------------- Page: 14 ----------------------
IEC 60755-1:2022 © IEC 2022 – 13 –
Replacement of first paragraph:
The moving contacts of all poles of multipole DC-RCDs shall be coupled so that all poles, except
the mid-point M-pole, if any, make and break substantially together, whether operated manually
or automatically.
Replacement of second paragraph:
The mid-point M-pole of three-pole DC-RCDs shall not close after and shall not open before the
other poles.
Replacement of second dash of ninth paragraph:
– a separate indicator.
If a separate indicator is used to indicate the position of the main contacts, this shall show the
colour red for the closed position and the colour green for the open position.
8.1.3 Clearance and creepage distances
Subclause 8.1.3 IEC 60755:2017 is applicable except as follows:
Replacement of second paragraph:
The clearances and creepage distances for insulation and for isolation shall be in accordance
with IEC 60664-1.
8.5 Operating characteristics
8.5.2 Operation in response to the type of residual current
Replacement of 8.5.2:
The tripping characteristic of DC-RCDs shall ensure adequate protection against residual
current w
...