SIST EN 50272-2:2002

SLOVENSKI STANDARD
SIST EN 50272-2:2002
01-september-2002
Safety requirements for secondary batteries and battery installations - Part 2:
Stationary batteries
Safety requirements for secondary batteries and battery installations -- Part 2: Stationary
batteries
Sicherheitsanforderungen an Batterien und Batterieanlagen -- Teil 2: Stationäre Batterien
Règles de sécurité pour les batteries et les installations de batteries -- Partie 2: Batteries
stationnaires
Ta slovenski standard je istoveten z: EN 50272-2:2001
ICS:
29.220.20 .LVOLQVNLVHNXQGDUQLþOHQLLQ Acid secondary cells and
EDWHULMH batteries
SIST EN 50272-2:2002 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 50272-2:2002

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SIST EN 50272-2:2002
EUROPEAN STANDARD EN 50272-2
NORME EUROPÉENNE
EUROPÄISCHE NORM June 2001
ICS 29.220.20
English version
Safety requirements for secondary batteries and battery installations
Part 2: Stationary batteries
Règles de sécurité pour les batteries et Sicherheitsanforderungen an Batterien
les installations de batteries und Batterieanlagen
Partie 2: Batteries stationnaires Teil 2: Stationäre Batterien
This European Standard was approved by CENELEC on 2000-08-01. 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.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.
This European Standard exists 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 Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic,
Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway,
Portugal, Spain, Sweden, Switzerland and United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2001 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50272-2:2001 E

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SIST EN 50272-2:2002
EN 50272-2:2001 - 2 -
Foreword
This European Standard was prepared by the Technical Committee CENELEC TC 21X, Secondary cells and
batteries.
The text of the draft was submitted to the formal vote and was approved by CENELEC on 2000-08-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2001-12-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2003-04-01
Annexes designated "informative" are given for information only.
In this standard, annexes A and B are informative.
______________

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Introductory note
1. For the preparation of EN 50272-2 the following European country’s national standards have
been taken into consideration:
Germany: DIN VDE 0510 Part 2
Batteries and battery installations
United Kingdom: BS 6133 for lead-acid batteries
BS 6132 for NiCd batteries
Sweden: SS 408 01 10 relating parts for rechargeable batteries,
erection and ventilation
Switzerland: SEV 1000-1 and SEV 1000-2 relating parts of instructions
for installations in buildings
Italy: Doc. D.P.R. 547, art. 302 and 303 ,
Safety in battery installations
CEI 21-6 Part 3
Netherlands: NEN 1010 relating parts of safety regulations for low voltage
installations
Austria ÖVE-C10 Part 2 ,
Batteries and battery installations
France NF C15-100 , article 554
Batteries d‘accumulateurs
Article EC10, Règlement de securité contre l‘incendie relatif aux
établissemments recevant du public
Only those paragraphs have been considered where common agreement was found or specific
need was recognised.
2. The described safety requirements comprise the protective measures to protect from hazards
generated by the electricity, the electrolyte, and the explosive gases when using secondary
batteries. In addition measures are described to maintain the functional safety of batteries and
battery installations.
3. For the electrical safety (protection against electric shock) under clause 5 this document refers to
HD 384.4.41 (IEC 60364-4-41). The pilot function of this standard is fully observed by indication
of cross-reference numbers of the relevant clauses. But interpretation is given where adoption to
direct current (DC) circuits is required.
4. This safety standard comes into force with the date of publication and applies to all new batteries
and battery installations. Previous installations shall conform with the existing national standards
at the time of installation. In case of redesign of old installations this standard applies.

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EN 50272-2:2001 - 4 -
Contents
Page
1 Scope. 5
2 Main applications . 5
3 Normative references. 5
4 General definitions . 6
5 Protection against electric shock . 8
6 Disconnection and separation. 14
7 Prevention of short circuits and protection from other effects of electric current . 14
8 Provisions against explosion hazards. 16
9 Provision against electrolyte hazard . 19
10 Accommodation, housing . 20
11 Charge current requirements. 22
12 Identification labels, warning notices and instructions for use, installation and maintenance. 23
13 Transportation, storage, disposal and environmental aspects. 24
14 Inspection and monitoring . 24
Annex A (informative) Charging methods, modes of operation. 25
Annex B (informative) Calculation of safety distance d to protect against explosion hazards. 29

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1 Scope
This European Standard applies to stationary secondary batteries and battery installations with
a maximum voltage of DC 1500 V (nominal) and describes the principal measures for
protections against hazards generated from:
- electricity,
- gas emission,
- electrolyte.
It provides requirements on safety aspects associated with the erection, use, inspection,
maintenance and disposal.
It covers lead-acid and NiCd batteries.
2 Main applications
Examples for the main applications are:
- Telecommunications,
- Power Station Operation,
- Central Emergency Lighting and Alarm Systems,
- Uninterruptible Power Supplies,
- Stationary Engine Starting,
- Photovoltaic Systems.
3 Normative references
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of
any of these publications apply to this European Standard only when incorporated in it by
amendment or revision. For undated references the latest edition of the publication referred to
applies (including amendments).
EN 166 Eye protection
EN 345 Safety footwear for professional use
EN 50091-1-2 Uninterruptible power systems (UPS)
General and safety requirements for UPS used in restricted access
locations
EN 50178 Electronic equipment for use in power installations
EN 60079-10 Electrical apparatus for explosive gas atmospheres
Part 10: Classification of hazardous areas (IEC 60079-10)
EN 60529 Degrees of protection provided by enclosures (IP code)
(IEC 60529)
EN 60623 Vented nickel-cadmium prismatic rechargeable single cells
(IEC 60623)
EN 60896-1 Stationary lead-acid batteries - General requirements and methods of test
Part 1: Vented types (IEC 60896-1)
EN 60896-2 Stationary lead-acid batteries - General requirements and methods of test
Part 2: Valve-regulated types (IEC 60896-2)
EN 60900 Hand tools for live working up to 1 kV a.c. and 1,5 kV d.c.
(IEC 60900, mod.)
EN 60950 Safety of information technology equipment (IEC 60950, mod.)
EN 60990 Methods of measurement of touch-current and protective conductor
current (IEC 60990)

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EN 61140 Protection against electric shock - Common aspects for installation and
equipment (IEC 61140)
EN 61660-1 Short-circuit currents in d.c. auxiliary installations in power plants and
substations -- Part 1: Calculation of short-circuit currents (IEC 61660-1)
EN 61660-2 Short-circuit currents in d.c. auxiliary installations in power plants and
substations -- Part 2: Calculation of effects (IEC 61660-2)
HD 193 Voltage bands for electrical installations of buildings
(IEC 60449)
HD 366 Classification of electrical and electronic equipment with regard to
protection against electric shock (IEC 60536)
HD 384.4.41 Electrical installations of buildings
Part 4: Protection for safety -- Chapter 41: Protection against electric
shock (IEC 60364-4-41, mod.)
HD 384.4.43 Electrical installation of building
Part 4: Protection for safety -- Chapter 43: Protection against overcurrent
(IEC 60364-4-43)
HD 384.5.53 Electrical installation of buildings
Part 5: Selection and erection of electrical equipment (IEC 60364-5-53)
HD 384.5.54 Electrical installations of buildings
Part 5: Selection and erection of electrical equipment
Chapter 54: Earthing arrangements and protective conductors
(IEC 60364-5-54, mod.)
HD 384.7.706 Electrical installation of buildings
Part 7: Requirements for special installations or locations
Section 706: Restrictive conductive locations (IEC 60364-7-706)
HD 625.1 Insulation co-ordination for equipment in low-voltage systems
Part 1: Principles, requirements and tests (IEC 60664-1)
IEC 60050-486 International Electrotechnical Vocabulary,
Chapter 486: Secondary cells and batteries
IEC/TR 60755 General requirements for residual current operated protective devices
IEC 61201 Extra-low voltage (ELV) - Limit values
IEC 61340-4-1 Electrostatics - Part 4: Standard test methods for specific applications -
Section 1: Electrostatic behaviour of floor coverings and installed floors
ISO 3864 Safety colours and safety signs
EC Directive 91/157/EEC Batteries and accumulators containing certain dangerous
substances
EC Directive 93/86/EEC Adaptation to technical progress of Directive 91/157/EEC
4 General definitions
4.1 (secondary) cell; (rechargeable) cell; single cell
An assembly of electrodes and electrolyte which constitutes the basic unit of a secondary
battery. (see IEC 60050-486-01-02)
NOTE  This assembly is contained in an individual case and closed by a cover.
4.2 vented (secondary) cell
A secondary cell having a cover provided with an opening through which gaseous products
may escape. (see IEC 60050-486-01-18)

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4.3 valve regulated (secondary) cell
A secondary cell which is closed under normal conditions but has an arrangement which allows
the escape of gas if the internal pressure exceeds a predetermined value. The cell cannot
normally receive addition to the electrolyte. (see IEC 60050-486-01-20)
4.4 gastight sealed (secondary) cell
A secondary cell which remains closed and does not release either gas or liquid when operated
within the limits of charge and temperature specified by the manufacturer. The cell may be
equipped with a safety device to prevent dangerously high internal pressure. The cell does not
require addition to the electrolyte and is designed to operate during its life in its original sealed
state. (see IEC 60050-486-01-21)
4.5 secondary battery
Two or more secondary cells connected together and used as a source of electrical energy.
(see IEC 60050-486-01-03)
4.6 lead-acid battery
A secondary battery in which the electrodes are made mainly from lead and the electrolyte is a
sulphuric acid solution (H2SO4). (see IEC 60050-486-01-04)
4.7 nickel-cadmium battery
An alkaline secondary battery in which the positive material is made mainly from nickel and the
negative material is made mainly from cadmium (see IEC 60050-486-01-07). The electrolyte is
an alkaline solution (potassium hydroxide, KOH).
4.8 stationary battery
A secondary battery which is designed for service in a fixed location and is not habitually
moved from place to place during the operating life. It is permanently connected to the DC
power supply (fixed installation).
4.9 monobloc battery
A secondary battery in which the plate packs are fitted in a multi-compartment container.
(see IEC 60050-486-01-17)
4.10 electrolyte
A liquid or solid phase containing mobile ions which render the phase ionically conductive.
(see IEC 60050-486-02-19)
4.11 gassing; gas emission
The formation of gas produced by electrolysis of the electrolyte.
(see IEC 60050-486-03-24)
4.12 charge; charging (of a battery)
An operation during which a battery receives from an external circuit electrical energy which is
converted into chemical energy. (see IEC 60050-486-01-11)
4.13 float charge
An operation during which the battery is permanently connected to a source of constant voltage
sufficient to maintain the battery in fully charged condition and to recharge the battery in a
specified time. (see IEC 60050-486-04-10, floating battery)
4.14 float (charge) voltage
The constant voltage needed to keep the cell or battery charged.

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4.15 float charge current
The current resulting from the float charge.
4.16 boost charge
A partial charge generally at high-rate for a short period. (see IEC 60050-486-04-04)
4.17 boost charge voltage
The constant voltage -at higher voltage level- needed to recharge a battery in a specified time
and / or to restore full capacity after a longer period of float charging or insufficient recharge.
4.18 boost charge current
The current arising from the boost charge voltage.
4.19 discharge; discharging (of a battery)
An operation during which a battery delivers current to an external circuit by the conversion of
chemical energy into electrical energy. (see IEC 60050-486-01-12)
4.20 overcharge; overcharging (of a cell or battery)
Continued charging after the full charge of a cell or battery. (see IEC 60050-486-03-35)
5 Protection against electric shock
Measures shall be taken in stationary battery installations for protection against direct contact
and indirect contact
or
against both direct and indirect contact.
These measures are described in detail in HD 384.4.41 and EN 61140. The following clauses
describe the typical measures to be taken for battery installations and the resulting
amendments.
The appropriate equipment standards (EN 50178, HD 366/IEC 60536, EN 60990) apply to
batteries and direct current distribution circuits located inside equipment.
5.1 Protection against direct contact
In battery installations, protection shall be ensured against direct contact with live parts in
accordance with HD 384.4.41, subclause 412.1 to 412.4 inclusive.
The following protective measures apply:
”Protection by insulation of live parts”;
”Protection by barriers or enclosures”;
”Protection by obstacles”;
”Protection by placing out of reach”.
Protection by obstacles or by placing out of reach is expressly permitted in battery installations.
It requires however that batteries with nominal voltages from >DC 60 V to DC 120 V between
terminals and/or with nominal voltages from >DC 60 V to DC 120 V with respect to earth shall
be located in accommodation with restricted access, and batteries with a nominal voltage
above DC 120 V shall be located in locked accommodation with restricted access. Doors to
battery rooms and cabinets are regarded as obstacles and shall be marked with the warning
labels according to 12.1.

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Batteries with nominal voltages up to or equal DC 60 V do not require protection against direct
contact, as long the whole installation corresponds to the conditions for SELV (safety extra low
voltage) and PELV (protective extra low voltage) (see 5.3.1).
Short circuit protection may be required (see clause 7.1).
If protection by barriers or enclosures is applied, a degree of protection EN 60529 IP 2X or
IPXXB shall at least be used.
5.2 Protection against indirect contact
In battery installations, protection against indirect contact shall be applied in accordance with
HD 384.4.41, clause 413.
The following measures can be selected:
”Protection by automatic disconnection of supply”;
”Protection by use of Class II equipment or by equivalent insulation”;
”Protection by non-conducting locations” (used in specific applications only);
”Protection by earth-free local equipotential bonding” (used in specific applications only);
”Protection by electrical separation”.
A nominal touch voltage of DC 120 V shall not be exceeded (see HD 193, HD 384.4.41 and
IEC 61201).
Certain of these methods of protection require a protective conductor. Protective conductors or
conductors with a protective function shall not be disconnected by a switching device. No
switching device is permitted in a protective conductor. They shall not contain overcurrent
protection devices (see HD 384.4.41, clause 413). For dimensioning the cross-sectional areas
of protective conductors, see HD 384.5.54.
Battery stands or battery cabinets made from metal shall either be connected to the protective
conductor or insulated from the battery and the place of installation. This insulation shall
correspond to the conditions for protection by insulation according to HD 384.4.41, subclause
413.2. Other simultaneously accessible conductive parts, i.e. metal ducts, shall be out of reach.
For requirements on creepage distances and clearances, see HD 625.1, using a value of 4000
V for the high-voltage impulse test.
The following protective devices are used with direct current, as applicable to the type of power
system:
a) fuses;
b) overcurrent protective devices;
c) Residual current or differential protective devices (RCD’s), suitable for DC current;
NOTE  Residual current protective devices (RCD’s) in accordance with IEC 60755 shall be of type B suitable for
DC fault current.
d) insulation monitoring devices (e.g. in IT-systems);
e) fault-voltage operated protective devices (see HD 384.4.41, subclause 413.1.4.4).
5.2.1 Protection by automatic disconnection of supply
5.2.1.1 TN-System
In a TN-system (see HD 384.4.41, subclause 413.1.3) the positive or negative terminal (see
Figure 1 and Figure 2) or the central point (in special cases also an non-central point) of the
battery installation shall be connected to earth.

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The exposed conductive parts of the equipment shall be connected to the protective conductor
1) 2) 3)
(PE) , the PEN-conductor (PEN) , or the earthing functional and protective conductor (FPE) ,
which is connected to the point on the battery having earth potential. Additional earthing of the
protective conductor may be required in order to ensure that its potential deviates as little as
possible from earth potential.
For fixed mounted electrical equipment the disconnecting time shall be within 5 s after a fault
occurs.
NOTE  For portable equipment and socket-outlet circuits HD 384.4.41, subclause 413.1.3.3 applies.
L+
L-
PE
d.c. power source
FPE
PEN
battery
load
Figure1 - TN system with separate protective conductor (PE)
in the entire system (TN-S network)
In the TN-S system, the protective conductor (PE) must be free of load current.
L+
d.c. power source
battery
load
Figure 2 - TN system with functional earthing and protective (FPE, PEN)
combined with an external line conductor (TN-C) system)
In the TN-C system for DC-installations, the protective conductor and the earthed line
conductor carrying the load current are combined. The cross-sectional area of the PEN or FPE
2
conductor shall be at least 10 mm Cu.

1)
For definitions see HD 384.5.54.
2)
Introduced with reference to HD 384.5.54.
3)
For definitions see EN 60950.

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5.2.1.2 TT-System
In a TT-System (see Figure 3) the positive or negative pole or another point on the battery
installation shall be connected to earth (system earth electrode).
The exposed conductive parts of the electrical installation may be earthed individually, in
groups or collectively to a common earth electrode which is separate from the system earth
electrode.
All exposed conductive parts collectively protected by the same protective device, shall be
connected together with protective conductors to an earth electrode common to all those parts.
Simultaneously accessible conductive parts shall be connected to the same earth electrode
(HD 384.4.41, subclause 413.1.4.1).
Apart from the protective devices mentioned in 5.2, fault-voltage operated protective devices
are also applicable (HD 384.4.41, subclause 413.1.4.4 )
In TT-system circuits, when the protective device is an overcurrent protective device, the
disconnecting time for all equipment shall be within 5 s, after a fault occurs. According to
HD 384.4.41, subclause 413.1.4.4 overcurrent protective devices are only applicable for
protection against indirect contact, where a very low value earth resistor R exists.
a
NOTE  R is the sum of the resistance of the earth electrode and the protective conductors for the exposed conductive
a
parts.
For discrimination purpose disconnecting times of up to 1 s are admitted, when using residual
current devices.
L+
L-
d.c. power source
PE
PE
battery load
Figure 3 - TT system
5.2.1.3 IT-System
In an IT system (see Figure 4) no point of the battery installation is directly connected to earth.
It shall be insulated from earth or connected to earth through a sufficiently high impedance
(e.g. through an insulation monitoring device).
All exposed conductive parts of equipment shall be earthed individually, in groups or
collectively to a common earth electrode via a protective conductor.
Exposed conductive parts which are protected by a common protective device shall be
connected by protective conductors to a common earth electrode. Exposed conductive parts
which are simultaneously accessible shall be connected to the same earth electrode
(HD 384.4.41, subclause 413.1.5.1).

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Apart from the safety devices mentioned in 5.2, insulation monitoring devices suitable for DC
voltages may also be used.
In an IT-system, disconnection is not required at the occurrence of the first fault from a live part to
the exposed conductive parts or to earth. If an insulation monitoring device is provided, this device
shall initiate an audible and/or visual signal (HD 384.4.41, subclause 413.1.5.4).
Precautions must be taken to prevent hazardous touch voltage levels in the event of a second
fault (e.g. disconnection by an overcurrent protective device, a residual current or fault voltage
protective device) (see HD 384.4.41, subclause 413.1.5.8).
L+
L-
PE
d.c. power source
R <
insulation
monitoring
device
battery
   load
Figure 4 - IT system
5.2.1.4 Intermediate DC current circuits with electrical connection to the AC supply
Systems of this type (Figure 5) are used, for example, in intermediate DC circuits of converter
devices, e.g. UPS systems according to EN 50091-1-2. Overcurrent protective devices are
necessary in all conductors which lead to the battery.
L1
L2
inverter
rectifier
battery PE
Figure 5 - Convertors with intermediate DC circuit (IT-System) (Example)
It shall be ensured that no AC voltage appears at the battery terminals whose rms voltage
value with respect to earth is above the maximum battery charging voltage. To ensure this, the
DC system can be provided with an appropriate detection device, which either monitors the
fault or disconnects the rectifier circuit.

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The protective provisions applied in the single/three-phase AC supply shall -where technically
possible- be retained for the DC circuit, and if necessary extended by suitable ancillary
components so that, in the event of a fault, no hazardous touch voltage (> AC 50 V or
> DC 120 V) remains at the exposed conductive parts of the equipment.
NOTE  Residual current protective devices(RCD’s) in accordance with IEC 60755 shall be of type B suitable for DC fault
current.
5.2.2 Protection by use of Class II equipment or by equivalent insulation
Protection by double or reinforced insulation must be employed for electrical equipment to
comply with protection Class II according to HD 366/IEC 60536 or equipment with equivalent
insulation (see HD 384.4.41, subclause 413.2.1.1)
5.2.3 Protection by electrical separation
For the application of protection by electrical separation see HD 384.4.41, subclause 413.5.
A separation source must be used as the source of supply (HD 384.4.41, subclause 413.5.1.1).
An ”equivalent current source” within the meaning of HD 384.4.41, subclause 413.5.1.1 is a
battery with isolated mounting during discharge. The separation shall comply with the test
requirements for protective insulation in accordance with HD 384.4.41, subclause 413.2.4.
5.3 Protection against both direct and indirect contact
The protective provisions described in 5.3.1 (safety extra low voltage, SELV) and 5.3.2
(protective extra low voltage, PELV) shall only be used for battery installations with nominal
voltages up to DC 120 V.
They simultaneously meet the requirements for protection against both direct and indirect
contact.
NOTE  In these cases the requirements for metal battery stands and cabinets specified in 5.2 do not apply.
5.3.1 Protection by SELV (safety extra low voltage) or by PELV (protective extra low
voltage) in accordance with HD 384.4.41, subclause 411.1
Protection against electric shock is ensured when the following conditions are met
simultaneously:
− The power source complies with the safety requirements in accordance with
HD 84.4.41, subclause 411.1.2, which reliably prevents the mains AC voltage
exceeding the values specified in HD 384.4.41, subclause 411.1.1 on the DC side in
the event of a fault.
− The arrangement of the circuits complies with HD 384.4.41, subclause 411.1.3.
It shall be ensured that live parts or exposed conductive parts of SELV circuits cannot
be connected to live parts or exposed conductive parts of circuits of an other circuit.
If the nominal DC voltage of the battery installation does not exceed DC 60 V and the above
conditions are met, then in general, protection against direct contact with live parts may be
omitted (exceptions see HD 384.7.706).
Where the nominal voltages exceeds DC 60 V then protection against direct contact with live
parts shall be provided by
− barriers or enclosures of minimum protection type EN 60529 IP 2X or IP XXB;
or
− insulation which withstands a test voltage of AC 500 V for 1 minute, (see HD 384.4.41,
subclause 411.1.4.3 for SELV circuits and HD 384.4.41, subclause 411.1.5.1 for PELV
circuits;
or
− protection through obstacles or distance which is expressly permitted in accordance
with 5.1 in battery installations and battery rooms, see HD 384.4.41, subclause 412.3.

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5.3.2 Protection by FELV (functional extra low voltage) without protective separation
If the nominal voltage does not exceed DC 120 V, but the conditions in accordance with 5.3.1,
- relevant to an electrochemical power source, which is independent or separated by
protection separation
and/or
- relevant to the arrangement of the circuits (e.g. connection of a conductor to the
protective conductor of
...