oSIST prEN 50156-1:2022

Electrical equipment for furnaces and ancillary equipment - Part 1: Requirements for application design and installation

This document applies to the application design and installation of electrical equipment, control circuits and safety-related systems for furnaces which are operated with solid, liquid or gaseous fuels and their ancillary equipment. It specifies requirements to meet the operating conditions of furnaces, to reduce the hazards of combustion and to protect the heated systems from damage e.g. by overheating.
Such furnaces and the electrical equipment can be part by way of example of the following plant:
a)   water heating systems;
b)   steam boiler installations (steam and hot-water boilers) and heat recovery steam boilers;
NOTE 1   The requirements of this document apply according to the electrical equipment of electrically heated steam boilers.
NOTE 2   Seagoing vessels and offshore facilities are governed by International Maritime Law and as such are not within the scope of this document. These requirements can be used for such facilities.
c)   warm air heaters;
d)   hot-gas heaters;
e)   heat exchanger systems;
f)   combustion chambers of stationary turbines;
g)   as long as no other standard is applicable for combined heat and power stations, we recommend the use of the requirements of this document;
This document can also be used as reference for electrical equipment requirements for thermo-processing equipment.
The requirements in this document are not applicable to electrical equipment for:
a)   non-electrically heated appliances and burner control systems for household and similar purposes;
b)   furnaces using technologies for the direct conversion of heat into electrical energy;
c)   combustion chambers of non-stationary prime movers and turbines;
d)   central oil supply systems for individual heating appliances;
e)   furnaces using solid fuels for heating purposes for household use with a nominal thermal output up to 1 MW;
f)   furnaces which are used to heat process fluids and gasses in chemical plant.
This document can be used as a basis for the requirements placed on electrical equipment for furnaces, which are excluded from its field of application.
This document specifies special requirements for the management of functional safety.

Elektrische Ausrüstung von Feuerungsanlagen und zugehörige Einrichtungen - Teil 1: Bestimmungen für die Anwendungsplanung und Errichtung

Equipements électriques d'installation de chaudière - Partie 1: Exigences pour la conception, pour l'application et l'installation

Le présent document s'applique à la conception d'application et à l'installation du matériel électrique, des circuits de commande et des systèmes relatifs à la sécurité des fours utilisés avec des combustibles solides, liquides ou gazeux et leurs équipements auxiliaires. Il spécifie les exigences pour respecter les conditions de fonctionnement des fours, pour réduire les dangers de combustion et pour protéger les systèmes chauffés contre les dommages dus par exemple à une surchauffe.
Ces fours et le matériel électrique peuvent faire partie des installations suivantes, par exemple:
a)   systèmes de chauffage à eau;
b)   installations de chaudière à vapeur (chaudières à vapeur et à eau chaude) et chaudières à vapeur à récupération de chaleur;
NOTE 1   Les exigences du présent document s'appliquent en conséquence au matériel électrique de chaudières à vapeur chauffées électriquement.
NOTE 2   Les navires de haute mer et les installations en mer sont régis par le droit maritime international et, de ce fait, n'entrent pas dans le domaine d'application du présent document. Ces exigences peuvent être utilisées pour ces installations.
c)   réchauffeurs à air chaud;
d)   réchauffeurs à gaz chaud;
e)   systèmes d'échangeur de chaleur;
f)   chambres de combustion de turbines fixes;
g)   il est recommandé d'utiliser les exigences du présent document pour autant qu'aucune autre norme ne s'applique aux centrales électriques et thermiques combinées.
Le présent document peut également être utilisé en tant que référence pour les exigences de matériel électrique de l'équipement de thermotraitement.
Les exigences du présent document ne s'appliquent pas au matériel électrique suivant:
a)   appareils non chauffés électriquement et systèmes de commande de brûleur pour applications domestiques et analogues;
b)   fours qui utilisent des technologies de conversion directe de chaleur en énergie électrique;
c)   chambres de combustion de moteurs d'entraînement et de turbines non fixes;
d)   systèmes centraux d'alimentation en combustible pour appareils de chauffage individuels;
e)   fours qui utilisent des combustibles solides aux fins de chauffage pour usages domestiques de puissance thermique nominale inférieure ou égale à 1 MW;
f)   fours utilisés pour chauffer des fluides et gaz de traitement dans des installations chimiques.
Le présent document peut servir de base pour les exigences relatives au matériel électrique des fours qui n'entrent pas dans son domaine d'application.
Le présent document spécifie les exigences particulières de gestion de la sécurité fonctionnelle.

Električna oprema za peči in pomožno opremo - 1. del: Zahteve za zasnovo in vgradnjo

General Information

• Status: Not Published
• Public Enquiry End Date: 31-Dec-2022
• ICS: 27.060.01 - Burners and boilers in general
• Technical Committee: I09 - Imaginarni 09
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 19-Oct-2022
• Due Date: 08-Mar-2023
• Completion Date: 06-Jan-2023
• Directive: 2014/35/EU - Directive 2014/35/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of electrical equipment designed for use within certain voltage limits
• Mandate: M/511 - Mandate to CEN, CENELEC and ETSI relating to harmonised standards in the field of the Low Voltage Directive
• Ref Project: prEN 50156-1 - Electrical equipment for furnaces and ancillary equipment - Part 1: Requirements for application design and installation

Relations

• Revised: SIST EN 50156-1:2015 - Electrical equipment for furnaces and ancillary equipment - Part 1: Requirements for application design and installation
• Effective Date: 06-Oct-2020

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 50156-1:2022
01-december-2022
Električna oprema za peči in pomožno opremo - 1. del: Zahteve za zasnovo in
vgradnjo
Electrical equipment for furnaces and ancillary equipment - Part 1: Requirements for
application design and installation
Elektrische Ausrüstung von Feuerungsanlagen und zugehörige Einrichtungen - Teil 1:
Bestimmungen für die Anwendungsplanung und Errichtung
Equipements électriques d'installation de chaudière - Partie 1: Exigences pour la
conception, pour l'application et l'installation
Ta slovenski standard je istoveten z: prEN 50156-1
ICS:
27.060.01 Gorilniki in grelniki vode na Burners and boilers in
splošno general
oSIST prEN 50156-1:2022 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 50156-1:2022

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oSIST prEN 50156-1:2022


EUROPEAN STANDARD DRAFT
prEN 50156-1
NORME EUROPÉENNE

EUROPÄISCHE NORM

October 2022
ICS 27.060.01 Will supersede EN 50156-1:2015
English Version
Electrical equipment for furnaces and ancillary equipment - Part
1: Requirements for application design and installation
Equipements électriques d'installation de chaudière - Partie Elektrische Ausrüstung von Feuerungsanlagen und
1: Exigences pour la conception, pour l'application et zugehörige Einrichtungen - Teil 1: Bestimmungen für die
l'installation Anwendungsplanung und Errichtung
This draft European Standard is submitted to CENELEC members for enquiry.
Deadline for CENELEC: 2023-01-06.

It has been drawn up by CLC/BTTF 132-2.

If this draft becomes a European Standard, CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CENELEC in three official versions (English, French, German).
A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to
the CEN-CENELEC Management Centre has the same status as the official versions.

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

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.



European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Project: 72741 Ref. No. prEN 50156-1 E

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Contents Page
European foreword . 6
Introduction . 8
1 Scope .10
2 Normative references .10
3 Terms and definitions .12
4 General requirements .20
4.1 Concept and scope definition .20
4.2 Environmental requirements .20
4.2.1 General .20
4.2.2 Environmental and operating conditions .20
4.2.3 Electromagnetic compatibility.20
4.2.4 Ambient temperature .21
4.2.5 Humidity.21
4.2.6 Contamination .21
4.2.7 Vibration and shock .22
4.2.8 Equipment used in flammable atmospheres .22
4.3 Power supply .22
4.3.1 General .22
4.3.2 Power stations .22
5 Incoming supply connections and devices for disconnecting and emergency stop.22
5.1 Incoming supply and equipment connections .22
5.1.1 Types of connection .22
5.1.2 Terminations .23
5.2 Devices for disconnecting power supplies .24
5.2.1 General .24
5.2.2 Disconnecting switch .25
5.2.3 Excluded circuits .25
5.3 Emergency stop .25
5.3.1 General .25
5.3.2 Emergency stop device for furnaces in heating installations .26
5.3.3 Emergency stop device for other furnaces, e.g. steam boilers .26
5.3.4 Application as isolating switch .26
6 Protection against electric shock .26
6.1 Protection against direct contact .26
6.2 Protection against indirect contact .26
7 Environmental protection of the equipment .27
7.1 Protection against ingress of solid foreign bodies .27
7.2 Protection against water .27
8 Equipotential bonding .27
8.1 General .27
8.2 Equipotential bonding as a protective measure in case of indirect contact .27
8.3 Equipotential bonding for the purpose of lightning protection .28
8.4 Functional equipotential bonding .28
9 Auxiliary circuits .28
9.1 Supply to auxiliary circuits .28
9.1.1 Supply from 3-phase or AC systems .28
9.1.2 Supply from DC mains .29
9.1.3 Auxiliary circuits connected between the line conductors .29
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9.2 Voltage for auxiliary circuits . 29
9.2.1 Operating voltage of auxiliary circuits . 29
9.2.2 Preferred nominal voltages . 30
9.3 Connection to the protective conductor . 30
9.4 Overcurrent protection of auxiliary circuits . 30
9.4.1 Rating of overcurrent protective devices . 30
9.4.2 Overcurrent protection of auxiliary circuits connected to the protective conductor . 30
9.4.3 Overcurrent protection of auxiliary circuit with the middle conductor connected to the
protective conductor . 30
9.4.4 Overcurrent protection of auxiliary circuits with no electrical connection to the protective
conductor . 30
9.4.5 Overcurrent protection of control system supply transformers . 31
9.4.6 Rating and setting of overcurrent protection . 31
9.5 Measures to prevent danger from short circuits to exposed conductive parts or earth . 31
9.6 Influence of capacitance and leakage resistance . 31
10 Additional requirements for the application of a safety-related system . 31
10.1 General safety requirements . 32
10.1.1 General principles of the safety life cycle. 32
10.1.2 Objective . 33
10.1.3 Requirements . 35
10.1.4 Planning . 41
10.2 Concept and scope definition . 46
10.2.1 Objective . 46
10.2.2 Requirements . 46
10.2.3 Verification . 47
10.3 Hazard and risk analysis . 47
10.3.1 Objective . 47
10.3.2 Requirements . 47
10.3.3 Verification . 48
10.4 Safety requirements allocation . 50
10.4.1 Objective . 50
10.4.2 Requirements . 50
10.4.3 Measures for fault avoidance . 52
10.4.4 Verification . 52
10.5 Design . 53
10.5.1 Objective . 53
10.5.2 Requirements . 53
10.5.3 Measures for fault avoidance . 60
10.5.4 Consideration of times. 60
10.5.5 Hardware design . 61
10.5.6 Plant specific application software . 65
10.5.7 Periodical test . 68
10.5.8 Documentation . 68
10.5.9 Verification . 68
10.6 Installation and commissioning . 68
10.6.1 Objective . 68
10.6.2 Requirements . 68
10.6.3 Measures for fault avoidance . 69
10.6.4 Verification . 70
10.7 Safety validation . 71
10.7.1 Objective . 71
10.7.2 Requirements . 71
10.7.3 Measures for fault avoidance . 74
10.8 Operation and maintenance . 75
10.8.1 Objective . 75
10.8.2 Requirements . 75
10.9 Modification and retrofit . 79
10.9.1 Causes for modification and/or retrofit . 79
10.9.2 Objectives . 79
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10.9.3 Requirements .79
10.9.4 Measures against unauthorised changes or overriding .80
10.9.5 Verification .80
10.10 Decommissioning .80
10.10.1 Objectives .80
10.10.2 Requirements .81
10.10.3 Verification .81
10.11 Assessment .81
10.11.1 Objectives .81
10.11.2 Verification .81
11 Electrical equipment .81
11.1 General requirements .81
11.2 Creepage distances and clearances .82
11.3 Motors .82
11.4 Transformers .82
11.5 Switching devices .82
11.6 Operator control devices .82
11.7 Immersion electrodes .83
11.8 Trace heating systems .83
12 Cables and cords .83
12.1 General requirements .83
12.2 Insulation .83
12.3 Current-carrying capacity .84
12.4 Conductors of separate circuits .84
13 Warning signs and item designation .84
13.1 Warning signs .84
13.2 Functional identification .84
13.3 Item designations .85
14 Technical documentation .85
14.1 General .85
14.2 Documentation describing functions and connections .85
14.2.1 General .85
14.2.2 Documentation describing functions .85
14.2.3 Requirements for periodical tests .86
14.2.4 Documentation describing connections .86
14.2.5 Documentation describing the process .86
14.2.6 Documentation of the risk assessment .86
14.3 Documents for type approved components .86
14.4 Documentation of the application software .86
Annex A (informative) Configurations of programmable safety devices (PSD) with reference to
EN 61508 .88
A.1 General .88
A.2 Configuration 1oo1 .89
A.3 Configuration 1oo1D .90
A.4 Configuration 1oo2 .91
A.5 Configuration 1oo2D .92
A.6 Configuration 2oo3 .93
A.7 Configuration 2oo3D .95
Annex B (informative) Lifecycle of programmable safety device.96
Annex C (informative) Management of functional safety .97
Annex D (informative) Examples of determining the safety integrity level SIL using the risk graph
method .98
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D.1 General . 98
D.2 Risk parameter C (Consequences of the hazardous event) . 98
D.3 Risk parameter F (Frequency and duration of the time spent in the hazard area) . 98
D.4 Risk parameter P (Possibility of preventing the hazardous event) . 98
D.5 Risk parameter W (Likelihood of occurrence of the hazardous event) . 98
Annex ZZ (informative) Relationship between this European standard and the safety objectives of
Directive 2014/35/EU [2014 OJ L96] aimed to be covered . 100
Bibliography . 101

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European foreword
This document (prEN 50156-1:2022) has been prepared by CLC/BTTF 132-2 “Revision of EN 50156 ‘Electrical
equipment for furnaces and ancillary equipment’”.
This document is currently submitted to the Enquiry.
The following dates are proposed:
• latest date by which the existence of this (doa) dor + 6 months
document has to be announced at national
level
• latest date by which this document has to be (dop) dor + 12 months
implemented at national level by publication of
an identical national standard or by
endorsement
• latest date by which the national standards (dow) dor + 36 months
conflicting with this document have to be (to be confirmed or
withdrawn modified when voting)
This document will supersede EN 50156-1:2015 and all of its amendments and corrigenda (if any).
prEN 50156-1:2022 includes the following significant technical changes with respect to EN 50156-1:2015:
— harmonization of the definitions to the new version of EN 61508;
— check and updating of the normative references;
— creation of the Annex ZZ for the harmonization to the new Low Voltage Directive;
— significant changes in Clause 4.1 and 10;
— EN 50156-3 will not be created.
This document has been prepared under a Standardization Request given to CENELEC by the European
Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s)
/ Regulation(s).
For relationship with EU Directive(s) / Regulation(s), see informative Annex ZZ, which is an integral part of this
document.
This document covers the Principle Elements of the Safety Objectives for Electrical Equipment Designed for
Use within Certain Voltage Limits 2014/35/EU [2014 OJ L96].
This document is the first part of a series of European standards which specify the requirements for equipment
of safety functions for furnaces, especially safety related system to protect personnel, the furnace with its
ancillary equipment against hazards related to heat generation, the heated system and to operate reliably during
normal conditions, and abnormal conditions which can be foreseen.
This document has been prepared by the German National Committee with the participation of experts of other
National Committees. It is currently divided into 2 parts under the generic title “Electrical equipment for furnaces
and ancillary equipment”:
— Part 1: Requirements for application design and installation;
— Part 2: Requirements for design, development and type approval of safety devices and subsystems;
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oSIST prEN 50156-1:2022
prEN 50156-1:2022 (E)
This document is based on EN 61508:2010 “Functional safety of electrical/electronic/ programmable electronic
safet
...