prEN 50288-7
(Main)Multi-element metallic cables used in analogue and digital communication and control - Part 7: Sectional specification for instrumentation and control cables
Multi-element metallic cables used in analogue and digital communication and control - Part 7: Sectional specification for instrumentation and control cables
This document covers multi-element metallic cables suitable for connecting instruments and control systems for analogue or digital signal transmission used in industrial processes carried out in commercial and industrial premises including cables that could be specified for use in Automated Infrastructure Management applications. They could be screened and optionally incorporate armouring and/or moisture or environmental protection layers. The cables are expected to have a mechanically robust construction and electrical transmission handling properties. The electrical, mechanical, transmission and environmental performance characteristics of the cables, related to their reference test methods are detailed in this specification. This sectional specification is to be read in conjunction with EN 50288-1:2013, which contains the essential provisions for its application. Cables covered by this document have maximum rated voltages U0 of 90 V AC, 300 V AC or 500 V AC. Multi-element cables for use in analogue, digital and control circuits are not designed to be used for power supply or to be connected directly to mains electricity supply or other low impedance sources. NOTE These cables are expected to be installed in accordance with the applicable local and national regulations. According to Annex 1 of mandate M/443 EN, depending upon the installation and application these cables might not necessarily fall under the regulation of EN 50575:2014+ A1:2016. Cables intended to have circuit integrity under fire conditions are covered by EN 50288-7-1. Thermocouple extension and compensating cables are covered by EN 50288-7-2.
Mehradrige metallische Daten- und Kontrollkabel für analoge und digitale Übertragung - Teil 7: Rahmenspezifikation für Instrumenten- und Kontrollkabel
Câbles métalliques à éléments multiples utilisés pour les transmissions et les commandes analogiques et numériques - Partie 7: Spécification intermédiaire pour les câbles d’instrumentation et de contrôle
Le présent document couvre les câbles à éléments multiples adaptés au raccordement des instruments et des systèmes de commande pour la transmission de signaux analogiques et numériques utilisés dans des processus industriels exécutés dans des locaux commerciaux et industriels, y compris les câbles pouvant être utilisés pour des applications relatives à la gestion d’infrastructure automatisée. Ils peuvent être écrantés et peuvent éventuellement incorporer une armure et/ou des couches de protection contre l’humidité ou l’environnement. Il est attendu que les câbles présentent une construction mécaniquement robuste et des propriétés de transmission électrique. Les caractéristiques électriques, mécaniques, de transmission et de performance environnementale des câbles, relatives à leurs méthodes d’essai référencées, sont détaillées dans la présente spécification. Les tensions assignées maximales des câbles couverts par le présent document sont de 300 V ou 500 V en courant alternatif. Les câbles à éléments multiples utilisés dans les circuits analogiques, numériques et de commande ne sont pas conçus pour être utilisés au sein d’une alimentation électrique ou pour être connectés directement aux réseaux d’alimentation électrique ou à d’autres sources à faible impédance. NOTE Ces câbles doivent être installés conformément aux réglementations locales et nationales applicables. Conformément à l’Annexe 1 du Mandat M/443 EN, ces câbles peuvent ne pas relever de l’EN 50575 en fonction de leur installation et de leur application. Les câbles destinés à conserver une intégrité des circuits en cas d'incendie sont couverts par le présent document. Il peut exister des cas où les câbles ont nécessairement des caractéristiques de température de fonctionnement supérieures à celles fournies en utilisant des matériaux spécifiés par la série EN 50290. D’autres matériaux adaptés sont à l’étude.
Večelementni kovinski kabli za analogne in digitalne komunikacije in krmiljenje - 7. del: Področna specifikacija za instrumentne in krmilne kable
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN 50288-7:2021
01-februar-2021
Večelementni kovinski kabli za analogne in digitalne komunikacije in krmiljenje - 7.
del: Področna specifikacija za instrumentne in krmilne kable
Multi-element metallic cables used in analogue and digital communication and control -
Part 7: Sectional specification for instrumentation and control cables
Mehradrige metallische Daten- und Kontrollkabel für analoge und digitale Übertragung -
Teil 7: Rahmenspezifikation für Instrumenten- und Kontrollkabel
Câbles métalliques à éléments multiples utilisés pour les transmissions et les
commandes analogiques et numériques - Partie 7: Spécification intermédiaire pour les
câbles d’instrumentation et de contrôle
Ta slovenski standard je istoveten z: prEN 50288-7
ICS:
33.120.20 Žice in simetrični kabli Wires and symmetrical
cables
oSIST prEN 50288-7:2021 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
oSIST prEN 50288-7:2021
---------------------- Page: 2 ----------------------
oSIST prEN 50288-7:2021
EUROPEAN STANDARD DRAFT
prEN 50288-7
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2020
ICS 33.120.10 Will supersede EN 50288-7:2005 and all of its
amendments and corrigenda (if any)
English Version
Multi-element metallic cables used in analogue and digital
communication and control - Part 7: Sectional specification for
instrumentation and control cables
Câbles métalliques à éléments multiples utilisés pour les Mehradrige metallische Daten- und Kontrollkabel für
transmissions et les commandes analogiques et analoge und digitale Übertragung - Teil 7:
numériques - Partie 7: Spécification intermédiaire pour les Rahmenspezifikation für Instrumenten- und Kontrollkabel
câbles d'instrumentation et de contrôle
This draft European Standard is submitted to CENELEC members for enquiry.
Deadline for CENELEC: 2021-02-26.
It has been drawn up by CLC/SC 46XC.
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,
Turkey 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
© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Project: 67768 Ref. No. prEN 50288-7 E
---------------------- Page: 3 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
Contents Page
European foreword . 2
1 Scope . 3
2 Normative references . 3
3 Definitions, symbols and abbreviations . 4
4 Cable construction . 4
4.1 Conductor . 4
4.2 Insulation . 5
4.3 Cable elements . 6
4.4 Identification of cabling elements . 6
4.5 Screening of cabling elements . 6
4.6 Cable make-up . 6
4.7 Longitudinal watertight filling . 6
4.8 Interstitial fillers . 6
4.9 Screening of the cable core . 7
4.10 Moisture barriers . 7
4.11 Protective wrappings . 7
4.12 Inner sheath . 7
4.13 Bedding layers . 8
4.14 Metallic protection . 8
4.15 Integral suspension strand . 8
4.16 Outer sheathing . 8
4.17 Rodent or insect protection . 9
4.18 Chemical and /or environmental protection . 9
5 Test methods and requirements for completed cables. 9
5.1 General . 9
5.2 Electrical tests . 9
5.3 Mechanical tests . 10
5.4 Environmental tests . 11
5.5 Fire performance test methods . 11
Annex A (normative) Insulation or sheath thickness and concentricity — Selection of samples
and evaluation of results . 13
Annex B (normative) Copper braid screening . 14
Annex C (normative) Determination of cable dimensions . 15
Annex D (informative) Thermocouple extension and compensating conductor combinations . 19
Annex ZZ (informative) Relationship between this European standard and the safety objectives
of Directive 2014/35/EU [2014 OJ L96] aimed to be covered . 21
Bibliography . 25
1
---------------------- Page: 4 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
European foreword
This document (prEN 50288-7:2020) has been prepared by SC46XC, “Multicore, multipair and quad data
communication cables”, of Technical Committee CENELEC TC 46X, “Communication cables”.
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 50288-7:2005 and all of its amendments and corrigenda (if any).
This document has been prepared under a mandate given to CENELEC by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive(s).
For the relationship with EU Directive(s) see informative Annex ZZ, which is an integral part of this document.
This document is to be read in conjunction with EN 50288-1, which contains the essential provisions for its
application.
LVD additions highlighted
2
---------------------- Page: 5 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
1 Scope
This document covers multi-element cables suitable for connecting instruments and control systems for
analogue or digital signal transmission used in industrial processes carried out in commercial and industrial
premises including cables that could be specified for use in Automated Infrastructure Management applications.
They could be screened and optionally incorporate armouring and/or moisture or environmental protection
layers.
The cables are expected to have a mechanically robust construction and electrical transmission handling
properties. The electrical, mechanical, transmission and environmental performance characteristics of the
cables, related to their reference test methods are detailed in this specification.
Cables covered by this document have maximum rated voltages of 300 V or 500 V a.c.
Multi-element cables for use in analogue, digital and control circuits are not designed to be used for power
supply or to be connected directly to mains electricity supply or other low impedance sources.
NOTE These cables are expected to be installed in accordance with the applicable local and national regulations.
According to Annex 1 of mandate M/443 EN, depending upon the installation and application these cables might
not necessarily fall under the regulation of EN 50575.
Cables intended to have circuit integrity in a fire are covered by this document.
There could be occasions when cables are required to have higher operating temperature ratings than those
provided by using materials specified by the EN 50290 series. Suitable alternative materials are under
consideration.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references, the
latest edition of the referenced document (including any amendments) applies.
EN 10218-1, Steel wire and wire products - General - Part 1: Test methods
EN 10244-2, Steel wire and wire products - Non-ferrous metallic coatings on steel wire - Part 2: Zinc or zinc
alloy coatings
EN 10257-1, Zinc or zinc alloy coated non-alloy steel wire for armouring either power cables or
telecommunication cables - Part 1: Land cables
EN 50200, Method of test for resistance to fire of unprotected small cables for use in emergency circuits
EN 50288-1:2013, Multi-element metallic cables used in analogue and digital communication and control - Part
1: Generic specification
EN 50289 (series), Communication cables — Specifications for test methods
EN 50290 (series), Communication cables
EN 50307, Lead and lead alloys - Lead and lead alloy sheaths and sleeves of electric cables
EN 50362, Method of test for resistance to fire of larger unprotected power and control cables for use in
emergency circuits
EN 60228, Conductors of insulated cables (IEC 60228)
EN 60332-1-2, Tests on electric and optical fibre cables under fire conditions - Part 1-2: Test for vertical flame
propagation for a single insulated wire or cable - Procedure for 1 kW pre-mixed flame (IEC 60332-1-2)
3
---------------------- Page: 6 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
EN 60332-3, (series), Tests on electric and optical fibre cables under fire conditions (IEC 60332-3 series)
EN 60584-1, Thermocouples - Part 1: EMF specifications and tolerances (IEC 60584-1)
EN 60584-3, Thermocouples - Part 3: Extension and compensating cables - Tolerances and identification
system (IEC 60584-3)
EN 60708, Low-frequency cables with polyolefin insulation and moisture barrier polyolefin sheath (IEC 60708)
EN 60754-1, Test on gases evolved during combustion of materials from cables - Part 1: Determination of the
halogen acid gas content (IEC 60754-1)
EN 60754-2, Test on gases evolved during combustion of materials from cables - Part 2: Determination of acidity
(by pH measurement) and conductivity (IEC 60754-2)
EN 60811-201, Electric and optical fibre cables - Test methods for non-metallic materials - Part 201: General
tests - Measurement of insulation thickness (IEC 60811-201)
EN 60811-202, Electric and optical fibre cables - Test methods for non-metallic materials - Part 202: General
tests - Measurement of thickness of non-metallic sheath (IEC 60811-202)
EN 61034-2, Measurement of smoke density of cables burning under defined conditions - Part 2: Test procedure
and requirements (IEC 61034-2)
IEC 60189-2, Low-frequency cables and wires with PVC insulation and PVC sheath — Part 2: Cables in pairs,
triples, quads and quintuples for inside installations
IEC 60331-1, Tests for electric cables under fire conditions — Circuit integrity — Part 1: Test method for fire
with shock at a temperature of at least 830°C for cables of rated voltage up to and including 0,6/1,0 kV and with
an overall diameter exceeding 20 mm
IEC 60331-2, Tests for electric cables under fire conditions — Circuit integrity — Part 2: Test method for fire
with shock at a temperature of at least 830°C for cables of rated voltage up to and including 0,6/1,0 kV and with
an overall diameter not exceeding 20mm
IEC 60331-21, Tests for electric cables under fire conditions — Circuit integrity — Part 21: Procedures and
requirements — Cables of rated voltage up to and including 0,6/1,0 kV
3 Definitions, symbols and abbreviations
For the purposes of this document, the terms and definitions given in EN 50288-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
4 Cable construction
4.1 Conductor
Conductors shall be solid, stranded or flexible plain or metal coated copper in accordance with Class 1, 2 or 5
2 2
of EN 60228 in the range of 0,5 mm to 2,5 mm . For multi-core cables the maximum conductor resistance
shall be as EN 60228, and for finished multi-pair, multi-triple and multi-quad cables the maximum resistance of
EN 60228 shall be increased by 2 %.
Conductor joints shall be as EN 50288-1.
4
---------------------- Page: 7 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
Stranded and flexible conductors shall consist of wires circular in cross section assembled, without insulation
between them, by concentric stranding or by bunching.
Conductors for thermocouple extension and compensating cables as described in Annex D shall be solid,
stranded or flexible. The materials shall comply with EN 60584-3.
When the installed length of cable results in a high conductor resistance, larger conductor sizes can be used.
Additional conductor wrapping of mineral tape(s) may be applied for circuit integrity in a fire. The thickness of
such mineral tape(s) shall not be included in the thickness of the insulation.
Designing the cable, consideration should be paid to the maximum admissible current stated in the detail
specification. It is assumed that the raise of temperature of the inner conductor when submitted to the maximum
current under nominal ambient conditions does not affect the mechanical properties of the cable. i.e. the
temperature rise due to the current is below the continuous maximum permitted temperature of the dielectric
and the sheath material.
All cables covered by this document may be subjected to voltages greater than 50 V AC or 75 V DC according
to the relevant sectional or detail specification.
In this case, care and attention shall be paid to the requirements of the “Principle Elements of the Safety
Objectives for Electrical Equipment Designed for Use within Certain Voltage Limits (LVD - 2014/35/EU)” by the
sectional or detail specification. Relevant sectional or detail specifications shall include a respective Annex ZZ.
However, cables covered by this document are not intended for direct connection to the mains electricity supply
or other low impedance sources.
4.2 Insulation
The insulating material shall be selected from those listed below. It shall be applied to comply with the
requirements of EN 50288-1.
PVC EN 50290-2-21
Polyethylene EN 50290-2-23
Polypropylene EN 50290-2-25
Halogen free flame retardant compound EN 50290-2-26
Cross-linked polyethylene EN 50290-2-29
Silicone rubber insulation Material specification is
under consideration
The minimum thickness at any point of the insulation shall not be less than the value given in Table 1, for the
specified voltage rating, and the concentricity shall not fall below 75 % when measured using the procedure in
Annex A.
There could be occasions when cables are required to have higher operating temperature ratings than those
provided by using materials specified by the EN 50290 series. Suitable alternative materials are under
consideration.
Table 1 — Minimum insulation thickness
Conductor size Minimum thickness
2 mm
mm
Voltage rating
300 V 500 V
0,5 0,26 0,44
0,75 0,26 0,44
1,0 0,26 0,44
5
---------------------- Page: 8 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
Conductor size Minimum thickness
2 mm
mm
Voltage rating
300 V 500 V
1,3 0,35 0,44
1,5 0,35 0,44
2,5 - 0,53
4.3 Cable elements
Cable elements shall be in accordance with EN 50288-1:2013, 4.3.
The lay length of a pair, triple or quad shall not exceed 100 mm for cables with conductor cross-
2 2
section ≤ 1,5 mm , nor 150 mm for cables with conductor cross-section 2,5 mm .
4.4 Identification of cabling elements
Unless otherwise specified e.g. by means of numbered cores or tapes, the coding for identification shall be as
given in IEC 60189-2 or EN 60708, as appropriate. The colours shall meet the requirements of
EN 50288-1:2013, 4.4.
Coloured or numbered non-hygroscopic binder tapes may be applied over screened cabling elements (see 4.5)
as identification.
4.5 Screening of cabling elements
When screening of individual cable elements is specified, it shall be selected from those listed below and applied
in accordance with EN 50288-1:2013, 4.5:
a) a plain or coated metal braid with a minimum filling factor of 0,6 when calculated in accordance with
Annex B;
b) a combination of a foil, and a plain or coated metal braid with a minimum filling factor of 0,3 when calculated
in accordance with Annex B. The use of a drain wire is optional when this type of screen is applied;
c) a foil applied with a minimum overlap of 20 % and with a drain wire in direct contact with the metallic side
of the foil.
Metal braid wire diameters are given in Table B.1.
4.6 Cable make-up
The cable elements shall be assembled together in concentric layers or in unit construction to form the cable
core.
The cable core assembly shall be protected by wrappings of non-hygroscopic tape.
Successive layers may be separated from each other by interlayer binders of non-hygroscopic tape.
4.7 Longitudinal watertight filling
When a longitudinal watertight filling is specified, it shall be selected from the methods given in
EN 50288-1:2013, 4.7.
4.8 Interstitial fillers
When fillers are used they shall meet the requirements of EN 50288-1:2013, 4.8.
6
---------------------- Page: 9 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
4.9 Screening of the cable core
The cable core shall be protected with a protective layer as described in 4.11 or 4.13 when it is covered with a
screen.
When screening of the cable core is specified, it shall be selected from those listed below, and applied in
accordance with EN 50288-1:2013, 4.9:
a) a plain or coated metal braid with a minimum filling factor of 0,6 when calculated in accordance with
Annex B;
b) a combination of a foil, and a plain or coated metal braid with a minimum filling factor of 0,3 when calculated
in accordance with Annex B. The use of a drain wire is optional when this type of screen is applied;
c) a foil applied with a minimum overlap of 20 % and with a drain wire in direct contact with the metallic side
of the foil.
Metal braid wire diameters are given in Table B.1.
Screening over the cable core may also be in the form of a laminated sheath (moisture barrier as 4.10 or multi-
layer sheath as 4.18. b).
4.10 Moisture barriers
When a moisture barrier is specified it shall be applied to meet the requirements of EN 50288-1:2013, 4.10 for
a laminated sheath, consisting of a longitudinal overlapped metallic tape, bonded within the overlapping and to
the inner surface of an extruded sheath. The tape shall coated on one or two sides where in the case of one
side coating a tinned copper drain wire shall be applied in direct contact with the metallic surface of the tape.
The thickness of the metallic part of the tape shall be at least 0,15 mm.
4.11 Protective wrappings
A wrapping layer may be applied under a sheath.
A wrapping layer may be applied under a metallic protection layer.
The wrapping layer shall be of a material compatible with the cable components with which it is in contact.
4.12 Inner sheath
When an additional inner sheath is applied under a metallic sheath (4.14) and may be applied under a lead
sheath (4.18), it shall be selected from the materials listed below. It shall comply with the requirements of
EN 50288-1:
a) PVC to EN 50290-2-22;
b) Polyethylene to EN 50290-2-24;
c) Halogen free flame retardant compound to EN 50290-2-27.
The nominal thickness shall be calculated in accordance with Table C.1.
The nominal thickness (ISRt) shall be calculated in accordance with the following formula:
IS = 0,04 x D + 0,7 mm (min 0,8 mm)
Rt
The minimum thickness at any point shall not fall below the nominal value by more than 15 % + 0,1 mm.
There could be occasions when cables are required to have higher operating temperature ratings than those
provided by using materials specified by the EN 50290 series. Suitable alternative materials are under
consideration.
7
---------------------- Page: 10 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
4.13 Bedding layers
A bedding layer shall be applied between a lead sheath and a metallic protection. This layer may be extruded
(materials as in 4.12) or comprise helically applied tape or tapes.
The bedding layer shall be extruded when gland diameter requirements are specified.
The nominal thickness shall be calculated in accordance with Table C.5, where the diameter under the bedding
layer (F ) is calculated in accordance with Table C.1.
L
There could be occasions when cables are required to have higher operating temperature ratings than those
provided by using materials specified by the EN 50290 series. Suitable alternative materials are under
consideration.
4.14 Metallic protection
Metallic protection, when specified, shall be in accordance with EN 50288-1:2013, 4.14.
When round or flat galvanised steel wires are used, the minimum thickness shall be 0,80 mm (see Annex C).
Flat galvanised steel wire may only be applied to cables where the diameter under the armour, calculated in
accordance with Annex C, is > 15 mm.
The round steel wires of single wire armour shall comply with the requirements of EN 10257-1 and EN 10218-1.
The coating of the wires shall comply with the requirements of EN 10244-2.
When a single or double layer of steel or brass tapes is used, the minimum thickness of tape shall be 0,20 mm
for steel and 0,075 mm for brass.
When a metal braid is specified the minimum wire diameter shall be 0,30 mm. The minimum filling factor shall
be 0,57 when calculated as Annex B.
Metal braid wire diameters are given in Annex C.
4.15 Integral suspension strand
Not applicable.
4.16 Outer sheathing
The outer sheathing material shall be appropriate to the operating environment and may be selected from the
materials listed below. It shall be applied in accordance with EN 50288-1:2013, 4.16:
a) PVC to EN 50290-2-22;
b) Polyethylene to EN 50290-2-24;
c) Halogen free flame retardant compound to EN 50290-2-27.
The nominal thickness (SRt) shall be calculated in accordance with the following formulae:
a) without metallic protection S = 0,04 x D + 0,7 mm (min 0,8 mm)
Rt
b) with metallic protection S = 0,028 x D + 1,1 mm (min 1,3 mm)
Rt
where D is the diameter under the outer sheath calculated in accordance with Table C.1.
For cables without metallic protection, the minimum thickness at a point shall not fall below the nominal value
by more than 15 % + 0,1 mm. The minimum average thickness, rounded to 0,1 mm, shall not be less than
nominal thickness.
For cables with metallic protection (4.14), the minimum thickness at any point shall not fall below the nominal
value by more than 20 % + 0,2 mm
8
---------------------- Page: 11 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
4.17 Rodent or insect protection
When rodent or insect protection is required, the method used shall be chosen from those in EN 50288-1:2013,
4.17.
There are no dimensional requirements.
4.18 Chemical and /or environmental protection
When chemical or environmental protection is required, one of the following methods shall be used.
a) Lead sheath
The lead sheath shall comply with EN 50307.
The nominal thickness (L ) of the lead or lead alloy sheath shall be calculated using the following formula:-
Rt
L = 0,03 x D + 0,7 mm (min of 0,8 mm)
Rt
where D is the diameter under the lead sheath, calculated in accordance with Table C.1.
The minimum thickness at any point shall not be less than 0,95 L – 0,1 mm.
Rt
b) Multi layer sheath
The multi layer sheaths shall comprise a laminated sheath (4.10) and an additional layer of polyamide.
The laminated sheath shall consist of a longitudinal overlapped aluminium tape bonded to an extruded layer of
high density polyethylene according to EN 50290-2-24. The thickness of the polyethylene layer shall be
calculated as in 4.12 with a minimum thickness of 1,0 mm.
The thickness of the aluminium tape shall be at least 0,15 mm without coating.
The thickness of the polyamide covering shall be at least 0,3 mm at any point irrespective of cable diameter.
NOTE A material specification for polyamide is under consideration.
5 Test methods and requirements for completed cables
5.1 General
Table 2 to Table 4 give the tests to be applied, together with the respective limits, in order to demonstrate
compliance with this specification.
5.2 Electrical tests
Table 2 — Low-frequency and d.c. electrical measurements
EN 50288- Parameter Test method Requirement
1:2013,
Clause No.
5.1.1.1 Conductor EN 50289-1-2 a
EN 60228 for multicore cables and
resistance
maximum shall be increased by 2 % for
multi-pair, multi-triple, and multi-quad
cables.
5.1.1.2 Conductor EN 50289-1-2 N/A
resistance
unbalance
9
---------------------- Page: 12 ----------------------
oSIST prEN 50288-7:2021
prEN 50288-7:2020 (E)
EN 50288- Parameter Test method Requirement
1:2013,
Clause No.
5.1.1.3 Dielectric strength EN 50289-1-3 Duration
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.