HD 60364-4-46:2016

Low-voltage electrical installations - Part 4-46: Protection for safety - Isolation and switching

This Harmonization Document deals with – non-automatic local and remote isolation and switching measures which prevent or remove dangers associated with electrical installations or electrically powered equipment; and – switching for the control of circuits or equipment.

Errichten von Niederspannungsanlagen - Teil 4-46: Schutzmaßnahmen - Trennen und Schalten

Installations électriques à basse tension - Partie 4-46 : Protection pour assurer la sécurité - Sectionnement et commande

Nizkonapetostne električne inštalacije - 4-46. del: Zaščitni ukrepi - Ločevanje in stikanje

Ta harmonizacijski dokument obravnava
– ukrepe za neavtomatsko lokalno in oddaljeno ločevanje in stikanje, ki preprečujejo ali odstranjujejo nevarnosti v zvezi z električnimi inštalacijami ali električno opremo in
– stikanje za nadzor tokokrogov ali opreme.

General Information

• Status: Published
• Publication Date: 10-Nov-2016
• Withdrawal Date: 10-Nov-2019
• ICS: 29.120.50 - Fuses and other overcurrent protection devices
• ICS: 91.140.50 - Electricity supply systems
• Technical Committee: CLC/TC 64 - Electrical installations and protection against electric shock
• Drafting Committee: CLC/TC 64/WG 07 - Selection and erection of electrical equipment - Switchgear and controlgear
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 11-Nov-2016
• Due Date: 02-Apr-2017
• Completion Date: 11-Nov-2016
• Ref Project: SIST HD 60364-4-46:2017 - Low-voltage electrical installations - Part 4-46: Protection for safety - Isolation and switching

Relations

• Replaces: HD 384.4.46 S2:2001 - Electrical installations of buildings - Part 4: Protection for safety - Chapter 46: Isolation and switching
• Effective Date: 28-Jan-2023
• Amended By: HD 60364-4-46:2016/A11:2017 - Low-voltage electrical installations - Part 4-46: Protection for safety - Isolation and switching
• Effective Date: 23-Jan-2023

Overview

The HD 60364-4-46:2016 standard, issued by CLC, addresses low-voltage electrical installations with a focus on protection for safety through isolation and switching. This Harmonization Document provides essential guidance on non-automatic local and remote isolation and switching measures designed to prevent or eliminate risks associated with electrical installations and electrically powered equipment. It also covers switching systems used for controlling electrical circuits or equipment.

This standard is part of the broader HD 60364 series, which relates to electrical safety provisions in low-voltage installations across Europe, facilitating harmonization among member countries. The document emphasizes safety for persons, livestock, and property by ensuring correct isolation and switching operations.

Key Topics

• Isolation Requirements:
  Every electrical installation must include provisions for isolating power supplies at various points. Isolation devices should disconnect all live conductors to allow safe maintenance, prevent unintentional energizing, and ensure discharge of any residual electrical energy where required.

• Functional Switching:
  This relates to controlling parts of circuits independently, with guidelines ensuring appropriate switching devices are used-such as prohibiting single-pole switching in neutral conductors except for specific lighting circuit control. Functional switches must also manage alternative power sources without creating hazardous parallel connections.

• Auxiliary Circuit Protection:
  Auxiliary circuits must be designed and protected to avoid faults that could cause unintended equipment operation or malfunction, reducing risk in control systems.

• Motor Control Safety:
  Motor circuits should prevent automatic restarts after power failures or voltage drops when such restarts pose danger. There should also be provisions preventing hazardous reversal of motor direction after braking and ensuring phase reversals do not impair motor safety.

• Switching for Maintenance:
  Means for safely switching off equipment prior to mechanical maintenance must be provided, including protection against unintentional reactivation. Electrical isolation must correspond to the level of risk involved.

• Emergency Switching Off:
  The standard specifies requirements for emergency switch-off devices to quickly remove unexpected hazards. These devices must operate using a single action, cut power to all live conductors, and not introduce further risks during operation.

• Special National Conditions:
  The document outlines national deviations and local practices relevant to isolation and switching, such as neutral conductor treatment in specific countries like France, Germany, Norway, and the Netherlands.

Applications

HD 60364-4-46:2016 is critical for a broad range of applications, including:

• Industrial Electrical Installations:
  Ensures safety protocols during machine control and maintenance, protecting workers and equipment with reliable isolation and switching mechanisms.

• Residential and Commercial Buildings:
  Facilitates compliance with safety regulations for lighting, circuit control, and emergency power disconnection-critical for occupant safety.

• Electrical Equipment Control:
  Supports design of motor control circuits, auxiliary systems, and functional switching devices that comply with safety requirements, preventing hazards like unexpected startups or dangerous phase reversals.

• Emergency Safety Systems:
  Guides installation of emergency switching devices that allow quick disconnection to avoid electric shocks or fire hazards during unforeseen dangerous events.

Related Standards

This standard references and complements key documents within the HD 60364 series and other IEC standards, including:

• HD 60364-4-41: Protection against electric shock in low-voltage installations.
• HD 60364-5-53: Selection and erection of electrical equipment - Switchgear and controlgear.
• HD 60364-5-557: Selection and erection of electrical equipment – Auxiliary circuits.

These interconnected standards together ensure a comprehensive and harmonized approach for electrical safety in low-voltage environments, covering protection, equipment selection, and application-specific safety requirements.

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Keywords: low-voltage electrical installations, isolation and switching, electrical safety, functional switching, emergency switching off, motor control safety, electrical maintenance, CLC standard, HD 60364-4-46, electrical protection measures, national electrical regulations.

Standards Content (Sample)

SLOVENSKI STANDARD
01-januar-2017
1DGRPHãþD
SIST HD 384.4.46 S2:2002
1L]NRQDSHWRVWQHHOHNWULþQHLQãWDODFLMHGHO=DãþLWQLXNUHSL/RþHYDQMHLQ
VWLNDQMH
Low-voltage electrical installations - Part 4-46: Protection for safety - Isolation and
switching
Errichten von Niederspannungsanlagen - Teil 4-46: Schutzmaßnahmen - Trennen und
Schalten
Installations électriques à basse tension - Partie 4-46 : Protection pour assurer la
sécurité - Sectionnement et commande
Ta slovenski standard je istoveten z: HD 60364-4-46:2016
ICS:
29.120.50 9DURYDONHLQGUXJD Fuses and other overcurrent
PHGWRNRYQD]DãþLWD protection devices
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

HARMONIZATION DOCUMENT HD 60364-4-46

DOCUMENT D'HARMONISATION
HARMONISIERUNGSDOKUMENT
November 2016
ICS 29.120.50; 91.140.50 Supersedes HD 384.4.46 S2:2001
English Version
Low-voltage electrical installations -
Part 4-46: Protection for safety -
Isolation and switching
Installations électriques à basse tension -  Errichten von Niederspannungsanlagen -
Partie 4-46 : Protection pour assurer la sécurité - Teil 4-46: Schutzmaßnahmen -
Sectionnement et commande Trennen und Schalten
This Harmonization Document was approved by CENELEC on 2016-07-04. CENELEC members are bound to comply with the
CEN/CENELEC Internal Regulations which stipulate the conditions for implementation of this Harmonization Document at national level.
Up-to-date lists and bibliographical references concerning such national implementations may be obtained on application to the CEN-
CENELEC Management Centre or to any CENELEC member.
This Harmonization Document exists in three official versions (English, French, German).
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2016 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. HD 60364-4-46:2016 E
Contents Page
European foreword . 3
460 Introduction . 4
460.1 Scope . 4
460.2 Normative references . 4
461 General . 4
462 Isolation . 4
463 Functional switching (control) . 5
463.1 General . 5
463.2 Auxiliary circuits . 6
463.3 Motor control . 6
464 Switching off for mechanical maintenance . 6
465 Emergency switching off . 7
Annex A (informative) Explanation of emergency operation functions . 8
A.1 General . 8
A.2 Emergency operation . 8
A.3 Emergency stop . 8
A.4 Emergency start . 8
A.5 Emergency switching off . 8
A.6 Emergency switching on . 8
Annex B (normative)  Special national conditions . 9
Annex C (informative) A-deviations . 11

European foreword
This document (HD 60364-4-46:2016) was prepared by CLC/TC 64 “Electrical installations and
protection against electric shock”.
The following dates are fixed:
— latest date by which the document has to be implemented (dop) 2017-05-11
at national level by publication of an identical national
standard or by endorsement
— latest date by which the national standards conflicting with (dow) 2019-11-11
the document have to be withdrawn
This document supersedes HD 384.4.46 S2:2001.
edition: the contents of this document has been revised so that it only includes general requirements
on measures for isolation and switching to provide for the safety of persons, livestock and property.
NOTE Complementarily the text of HD 60364-5-537:2016 has been adapted to give requirements on
implementation of the measures provided in HD 60364-4-46:2016 and requirements for proper functioning, in
terms of selection and erection of electrical equipment for isolation and switching.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
460 Introduction
460.1 Scope
This Harmonization Document deals with
– non-automatic local and remote isolation and switching measures which prevent or remove
dangers associated with electrical installations or electrically powered equipment; and
– switching for the control of circuits or equipment.
460.2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
HD 60364-4-41, Low-voltage electrical installations – Part 4-41: Protection for safety – Protection
against electric shock (IEC 60364-4-41)
HD 60364-5-53:2015-11, Low-voltage electrical installations – Part 5-53: Selection and erection of
electrical equipment - Switchgear and controlgear
HD 60364-5-557:2013 + A11:2016, Low-voltage electrical installations – Part 5-557: Selection and
erection of electrical equipment – Auxiliary circuits (IEC 60364-5-55:2011/A1:2012)
461 General
461.1 According to the intended function(s), every device provided for isolation or switching shall
comply with the relevant requirements of HD 60364-5-53.
NOTE Clause 537 of HD 60364–5-53:2015-11 refers to HD 384.5.537 S2, which is now replaced by
HD 60364-5-537:2016.
461.2 In TN-C systems and in the TN-C part of the TN-C-S systems, the PEN conductor shall not be
isolated or switched.
In TN-S systems and in the TN-S part of the TN-C-S systems, isolation or switching of the neutral
conductor is not required if protective equipotential bonding is installed and either
– the neutral conductor is reliably connected to earth by a low resistance to meet the disconnection
times of the protective devices according to the requirements of HD 60364-4-41 or
– the distribution system operator (DSO) declares that either the PEN or the N conductor of the
supply is reliably connected to earth by a low resistance to meet the disconnection times of the
protective devices according to the requirements of HD 60364-4-41.
462 Isolation
462.1 Each electrical installation shall have provisions for isolation from each supply.
462.2 Every circuit shall be provided with isolation means for all live conductors, except as detailed in
461.2.
Provisions may be made for isolation of a group of circuits by a common means, if the service
conditions allow this.
462.3 Suitable means shall be provided to prevent any equipment from being unwantedly or
unintentionally energized/operated.
462.4 Where residual electrical energy is potentially present, suitable means shall be provided for its
discharge.
Where relevant, a warning label indicating the discharge time or the delay required before the
enclosure may be opened shall be provided.
NOTE Storage units do not need to be discharged since they are considered to be supply sources.
463 Functional switching (control)
463.1 General
463.1.1 Functional switching shall be provided for each part of a circuit which may require to be
controlled independently of other parts of the installation.
463.1.2
...