ETSI ES 203 408 V1.1.1 (2016-12)

ETSI ES 203 408 V1.1.1 (2016-12)
ETSI STANDARD
Environmental Engineering (EE);
Colour and marking of DC cable and connecting devices
---------------------- Page: 1 ----------------------
2 ETSI ES 203 408 V1.1.1 (2016-12)
Reference
DES/EE-0253
Keywords
cable, identification, power
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE
Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16
Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88
Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search

The present document may be made available in electronic versions and/or in print. The content of any electronic and/or

print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any

existing or perceived difference in contents between such versions and/or in print, the only prevailing document is the

print of the Portable Document Format (PDF) version kept on a specific network drive within ETSI Secretariat.

Users of the present document should be aware that the document may be subject to revision or change of status.

Information on the current status of this and other ETSI documents is available at

If you find errors in the present document, please send your comment to one of the following services:

No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying

The content of the PDF version shall not be modified without the written authorization of ETSI.

DECT , PLUGTESTS , UMTS and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members.

3GPP and LTE™ are Trade Marks of ETSI registered for the benefit of its Members and

GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.

Intellectual Property Rights ................................................................................................................................ 5

Foreword ............................................................................................................................................................. 5

Modal verbs terminology .................................................................................................................................... 5

Introduction ........................................................................................................................................................ 5

1 Scope ........................................................................................................................................................ 7

2 References ................................................................................................................................................ 7

2.1 Normative references ......................................................................................................................................... 7

2.2 Informative references ........................................................................................................................................ 8

3 Definitions, symbols and abbreviations ................................................................................................... 9

3.1 Definitions .......................................................................................................................................................... 9

3.2 Symbols ............................................................................................................................................................ 10

3.3 Abbreviations ................................................................................................................................................... 10

4 Electrical Distribution identification coverage ....................................................................................... 10

5 Identification principle ........................................................................................................................... 13

5.1 General rules .................................................................................................................................................... 13

5.2 Colour and marking of up to 400VDC conductor wires and cables for A3 or P interface ............................... 14

5.3 Additional recommendation for other DC voltage distribution cabling than up to 400VDC voltage of A3

interface ............................................................................................................................................................ 15

6 DC distribution devices additional colour and marking ......................................................................... 16

6.0 Colour and marking of up to 400VDC other distribution device than wires and cables .................................. 16

6.1 General requirements ....................................................................................................................................... 16

6.2 DC outputs from DC power systems with protective devices .......................................................................... 17

6.3 DC sub-distribution boards (with protective devices) ...................................................................................... 17

6.4 DC power plugs strips inside ICT equipment rooms and cabinets ................................................................... 17

7 Durability of Marking and reading errors limitation .............................................................................. 17

Annex A (informative): Review of Standards or common use of colour and marking of

A.1 Recommended colours for wires in IEC 60757 and IEC 60445 ............................................................ 18

A.2 Other Norms or specifications ................................................................................................................ 18

A.2.0 Introduction ...................................................................................................................................................... 18

A.2.1 Single and bicolours cables used in transportation sector ................................................................................ 18

A.2.2 Cables used in flying aircrafts, ground works machines and boats .................................................................. 19

A.2.3 Colour of personal computer power cables ...................................................................................................... 19

A.2.4 Machine Cabling .............................................................................................................................................. 19

A.2.5 Family of cables coding ................................................................................................................................... 19

A.3 Building distribution cable colour and marking standards ..................................................................... 20

A.3.1 Introduction ...................................................................................................................................................... 20

A.3.2 Low frequency cable and wire reference insulation colour in IEC 60304 ........................................................ 21

A.3.3 New (IEC 60445) ............................................................................................................................................. 21

A.3.3.0 General information om IEC 60445 ........................................................................................................... 21

A.3.3.1 Old Cable Colour Code reminder ............................................................................................................... 21

A.3.3.2 Harmonized Cable colours .......................................................................................................................... 21

A.3.3.3 Marking and alteration for cohabitation of harmonized and old Cable colours .......................................... 21

A.3.4 DC coding evolution ........................................................................................................................................ 22

A.3.4.1 BS 7671 case............................................................................................................................................... 22

A.3.4.2 Wire colours in China industry and standards ............................................................................................ 22

A.3.4.3 Wire Colours in up to 400VDC DC Solutions ............................................................................................ 23

A.3.4.4 Colours and marking of DC cables in Republic of Korea ........................................................................... 23

Annex B (informative): Justification of the identification wire colour choices................................. 24

Annex C (informative): Wire colour choice in colour range industrial specification ...................... 25

Annex D (informative): Bibliography ................................................................................................... 27

History .............................................................................................................................................................. 28

IPRs essential or potentially essential to the present document may have been declared to ETSI. The information

pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found

in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in

respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web

Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee

can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web

This ETSI Standard (ES) has been produced by ETSI Technical Committee Environmental Engineering (EE).

In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and

"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of

"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.

The present document has been developed to assist the ICT industry in their development and wider use of DC

powering solutions above the DC voltage range mainly used until now for Telecommunication networks equipment

The present document has been jointly developed by ETSI TC EE and ITU-T Study Group 5 in order to ensure an

equivalent technical content. It is published respectively by ITU as Recommendation ITU-T L.1203 [1] and ETSI

DC has been the main source of power of Telecommunication industry since the very beginning as it is efficient,

This solution is a well proven arrangement that has been used for a century in almost all of the sites in cohabitation with

AC for servers and other buildings services (lighting, facility plugs, lifts, etc.).

It is recognized that DC has many potential applications further to those for ICT and that such applications could benefit

from the standards defined in ITU/ETSI. It is also recognized that further standardization activities on LVDC is now

starting in other standardization organizations such as IEC. Thus ITU-T/ETSI will pursue cooperation with such

ETSI and ITU-T have standardized the widespread DC power interface at inputs of Telecom/ICT equipment used in

Telecom networks, Data centers, and customer sites. The legacy interface for billions of equipment is the SELV voltage

range so called -48V, where the plus pole is grounded as defined for example for interface "A" in ETSI

EN 300 132-2 [7]. Other complementary ETSI standards define a whole DC distribution including earthing and bonding

Higher voltages than 48 V are already widely used in Telecom networks for remote powering of signal repeaters on

copper or optical Telecom transmission lines, with a usual operation in symmetrical voltage up to +/- 200 V in RFT-C

Higher power density of ICT equipment and overall site power in MW for Data centers, have led to the use of higher

voltage firstly in AC single or 3 phases up to 400VAC at the input of servers. The need for resilience, energy efficiency

and cost optimization has pushed the introduction of the up to 400VDC power feeding interface standardized in ETSI

EN 300 132-3-1 [8] and in Recommendation ITU-T L.1200 [2]. This is now available on many servers and network

As there is a progressive introduction of the new DC power interface in cohabitation with existing -48 V and AC

distribution, a new standard ETSI EN 301 605 [10] has been introduced to ensure safety and proper operation especially

in mass bonding of EMC sensitive equipment and correct earthing connection to the building structure earthing

It appears that there is also a strong need for Telecom/Data centers operators, equipment manufacturers or installers and

end customers to clarify the colour and marking of cables in their installations. This would avoid confusion and errors

between the different AC and DC power interfaces and distributions used in the building and inside ICT systems.

Considering the user side, and very long background experience in use of DC of the Telecom sector, the present

document makes Recommendations directly contributing to safety principles laid down in IEC Guide 104 [i.9] and

ISO/IEC Guide 51 [i.10]. It accelerates and encourages the preparation of international standards of cable identification

intended for use by manufacturers, users or certification bodies. The present document makes reference to existing IEC

For useful information, colours of cables inside equipment are considered in annex A as DC is already widely used, e.g.

all the electronic being working only in DC, car and trucks electric circuit being in DC, solar PV power plants, etc.

The scope of the present document is to define common practice for identification of cabling or parts of the DC electric

distribution for the Telecom sites (buildings/rooms) feeding ICT and facilities equipment (power plant, cooling,

This applies to 400VDC cabling for Telecom, ICT equipment and environment equipment using interface defined in

ETSI EN 300 132-3-1 [8] or Recommendation ITU-T L.1200 [2] and avoids confusion between the DC colour and

marking of up to 400VDC distribution and the other power interfaces identification: -48VDC distribution for A

interface, AC and uninterrupted AC given by inverters or UPS used in the building.

• requirements for the colour and identification of separate wires used in DC distribution systems and

installations, and as much as possible inside equipment between A or P interface and end use;

• marking and identification of DC multiwire cables, connectors and any associated equipment for DC power

For DC wires in multiwire cables Recommendations are given for harmonization with separate wire requirements.

Recommendations are given on other distribution items (wires, cables and interconnection items) including the

functional earthing and bonding arrangement for distribution outside and inside equipment to avoid any confusion with

References are either specific (identified by date of publication and/or edition number or version number) or

non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the

Referenced documents which are not found to be publicly available in the expected location might be found at

NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee

The following referenced documents are necessary for the application of the present document.

[1] Recommendation ITU-T L.1203: "Colour and marking identification of up to 400VDC power

[2] Recommendation ITU-T L.1200 (2012): "Direct current power feeding interface up to 400 V at the

[3] IEC 60445 Ed 5.0 2010-08: "Basic and safety principles for man-machine interface, marking and

identification - Identification of equipment terminals, conductor terminations and conductors".

NOTE: IEC DB documents refer to Database of Graphical Symbol. Some are joint with ISO e.g. IEC 60417 and

[7] ETSI EN 300 132-2 (2016): "Environmental Engineering (EE); Power supply interface at the input

to telecommunications and datacom (ICT) equipment; Part 2: Operated by -48 V direct current

[8] ETSI EN 300 132-3-1 (2012): "Environmental Engineering (EE); Power supply interface at the

input to telecommunications and datacom (ICT) equipment; Part 3: Operated by rectified current

source, alternating current source or direct current source up to 400 V; Sub-part 1: Direct current

[9] ETSI EN 300 253 (2015): "Environmental Engineering (EE);Earthing and bonding of ICT

[10] ETSI EN 301 605 (2013): "Environmental Engineering (EE); Earthing and bonding of 400 VDC

References are either specific (identified by date of publication and/or edition number or version number) or

non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the

NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee

The following referenced documents are not necessary for the application of the present document but they assist the

[i.1] ETSI EN 302 099: "Environmental Engineering (EE); Powering of equipment in access network".

[i.2] IEC 60050-195 (1998): "IEC Terminology International Electrotechnical Vocabulary - Part 195:

[i.3] IEC 60050-826 (2004): "International Electrotechnical Vocabulary - Part 826: Electrical

[i.4] British Standard BS 7671 (2008): "Requirements for Electrical Installations. IET Wiring

[i.6] HD 324 S1 (1977): "Colored insulation and bare wire identification package".

[i.7] HD 384.5.514: "Identification, including 514.3: Identification of conductors, now withdrawn".

[i.8] IEC 60364-1 (2005): "Low-voltage electrical installations - Part 1: Fundamental principles,

[i.9] IEC Guide 104: "The preparation of safety publications and the use of basic safety publications

[i.10] ISO/IEC Guide 51: "Safety aspects - Guidelines for their inclusion in standards".

[i.11] IS0 6722 (2006): "Road vehicles - 60 V and 600 V single-core cables - Dimensions, test methods

[i.12] ISO 2574 (1994): "Flying machine electric cable - Identification marking".

http://www.iso.org/iso/fr/home/store/catalogue_ics/catalogue_detail_ics.htm?ics1=1&ics2=70&ics3=&cs

[i.13] ISO 9247 (1990): "Ground work machine - electric wire and cables -- identification and marking

NOTE: Available at http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=16897.

[i.14] IEC EN 60204-1 (2000): "Safety of machinery -Electrical equipment of machines -Part 1:General

NOTE: IEC/EN 60204-1 is now "Appliance of reference designations on machinery" in accordance with

ISO/IEC/EN 81346 (September 2010) EU Directive 2006/42/EC on machinery (www.81346.com).

[i.15] IEC 60304 (1982): "Standard colours for insulation for low-frequency cables and wires".

NOTE 1: Refered to as "RAL" in the present document, available at http://www.ralcolours.com/.

NOTE 2: RAL is the trade name of a colour matching system supplied by by the RAL gGmbH (RAL non-profit

LLC), which is a subsidiary of the German RAL Institute. This information is given for the convenience

of users of the present document and does not constitute an endorsement by ETSI of the product named.

Equivalent products may be used if they can be shown to lead to the same results.

NOTE 2: Pantone is the trade name of a colour matching system supplied Pantone Inc. This information is given

for the convenience of users of the present document and does not constitute an endorsement by ETSI of

the product named. Equivalent products may be used if they can be shown to lead to the same results.

[i.19] IEC 60446 (withdrawn) (2007): "Basic and safety principles for man-machine interface, marking

[i.20] CCSA YD/T 2378 (2011): "240V Direct Current Power supply system for Telecommunications".

For the purposes of the present document, the following terms and definitions apply:

400VDC: up to 400 Volt Direct Current voltage as defined in Recommendation ITU-T L.1200 [2]

electrical equipment: item used for purposes like generation, conversion, distribution or utilization of electric energy

(e.g. electrical machines, transformers, switch gear and control gear, measuring instruments, wiring systems,

identification: colour, graphical symbol, text in alphanumeric notation located on or adjacent to wire or cable terminals

NOTE: The two letters IT are coding one of the 3 families of electrical distribution where connection to earth is

made through high resistance or impedance device i.e. HRMG in ETSI EN 301 605 [10].

line conductor: AC phase conductor or DC pole conductor (deprecated) conductor which is energized in normal

operation and capable of contributing to the transmission or distribution of electric energy but which is not a neutral

TNS: AC distribution earthing arrangements as defined in IEC 60364-1 [i.8] where earthing and neutral wires are

A (interface) ICT/Telecom equipment -48VDC power interface in ETSI EN 300 132-2 [7]

A3 (interface) ICT/Telecom equipment up to 400VDC power interface in ETSI EN 300 132-3-1 [8]

P ICT equipment up to 400VDC power feeding interface in Recommendation ITU-T L.1200 [2]

• Building distribution with A interface (-48V), AC grid and inverter outputs power and A3 or P interface (up to

Figure 1 shows such building where distribution DC and protective earthing-[PE] bonding shall comply with

• Example of power feeding distribution of DC from centralized or decentralized permanent power supply at

Figure 1: DC distribution at building level from DC source to ICT/telecom systems

The identifying colour, graphical symbol or alphanumeric notation shall be located on, or adjacent to the corresponding

There shall be no confusion between the different identification modes i.e. wire insulation colour or coloured sleeve,

For identification of conductors, only colours and code among those permitted in IEC 60757 [4] shall be used (see

The identification of colour is required end to end in the installation for DC from DC source to interface A3 or P and

inside equipment till internal end use inside ICT or facilities equipment (Cooling, Power conversion, Sub distribution,

DC cabling inside power source equipment is recommended to use the same marking and colour as defined in the power

It is accepted to have different identification marking solution along an end to end distribution (insulation colour,

markers, sleeves, symbol and text, etc.) provided they are compliant to the present document. In that case wires and

The colour and marking identification requirements shall be applied on new installation at level of room or building and

Final draft ETSI ES 203 408 V1.0.2 (2016-10)
ETSI STANDARD
Environmental Engineering (EE);
Colour and marking of DC cable and connecting devices
---------------------- Page: 1 ----------------------
2 Final draft ETSI ES 203 408 V1.0.2 (2016-10)
Reference
DES/EE-0253
Keywords
cable, identification, power
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE
Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16
Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88
Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search

The present document may be made available in electronic versions and/or in print. The content of any electronic and/or

print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any

existing or perceived difference in contents between such versions and/or in print, the only prevailing document is the

print of the Portable Document Format (PDF) version kept on a specific network drive within ETSI Secretariat.

Users of the present document should be aware that the document may be subject to revision or change of status.

Information on the current status of this and other ETSI documents is available at

If you find errors in the present document, please send your comment to one of the following services:

No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying

The content of the PDF version shall not be modified without the written authorization of ETSI.

DECT , PLUGTESTS , UMTS and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members.

3GPP and LTE™ are Trade Marks of ETSI registered for the benefit of its Members and

GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.

Intellectual Property Rights ................................................................................................................................ 5

Foreword ............................................................................................................................................................. 5

Modal verbs terminology .................................................................................................................................... 5

Introduction ........................................................................................................................................................ 5

1 Scope ........................................................................................................................................................ 7

2 References ................................................................................................................................................ 7

2.1 Normative references ......................................................................................................................................... 7

2.2 Informative references ........................................................................................................................................ 8

3 Definitions, symbols and abbreviations ................................................................................................... 9

3.1 Definitions .......................................................................................................................................................... 9

3.2 Symbols ............................................................................................................................................................ 10

3.3 Abbreviations ................................................................................................................................................... 10

4 Electrical Distribution identification coverage ....................................................................................... 10

5 Identification principle ........................................................................................................................... 13

5.1 General rules .................................................................................................................................................... 13

5.2 Colour and marking of up to 400VDC conductor wires and cables for A3 or P interface ............................... 14

5.3 Additional recommendation for other DC voltage distribution cabling than up to 400VDC voltage of A3

interface ............................................................................................................................................................ 15

6 DC distribution devices additional colour and marking ......................................................................... 16

6.0 Colour and marking of up to 400VDC other distribution device than wires and cables .................................. 16

6.1 General requirements ....................................................................................................................................... 16

6.2 DC outputs from DC power systems with protective devices .......................................................................... 17

6.3 DC sub-distribution boards (with protective devices) ...................................................................................... 17

6.4 DC power plugs strips inside ICT equipment rooms and cabinets ................................................................... 17

7 Durability of Marking and reading errors limitation .............................................................................. 17

Annex A (informative): Review of Standards or common use of colour and marking of

A.1 Recommended colours for wires in IEC 60757 and IEC 60445 ............................................................ 18

A.2 Other Norms or specifications ................................................................................................................ 18

A.2.0 Introduction ...................................................................................................................................................... 18

A.2.1 Single and bicolours cables used in transportation sector ................................................................................ 18

A.2.2 Cables used in flying aircrafts, ground works machines and boats .................................................................. 19

A.2.3 Colour of personal computer power cables ...................................................................................................... 19

A.2.4 Machine Cabling .............................................................................................................................................. 19

A.2.5 Family of cables coding ................................................................................................................................... 19

A.3 Building distribution cable colour and marking standards ..................................................................... 20

A.3.1 Introduction ...................................................................................................................................................... 20

A.3.2 Low frequency cable and wire reference insulation colour in IEC 60304 ........................................................ 21

A.3.3 New (IEC 60445) ............................................................................................................................................. 21

A.3.3.0 General information om IEC 60445 ........................................................................................................... 21

A.3.3.1 Old Cable Colour Code reminder ............................................................................................................... 21

A.3.3.2 Harmonized Cable bcolours ........................................................................................................................ 21

A.3.3.3 Marking and alteration for cohabitation of harmonized and old Cable colours .......................................... 21

A.3.4 DC coding evolution ........................................................................................................................................ 22

A.3.4.1 BS 7671 case............................................................................................................................................... 22

A.3.4.2 Wire colours in China industry and standards ............................................................................................ 22

A.3.4.3 Wire Colours in up to 400VDC DC Solutions ............................................................................................ 23

A.3.4.4 Colours and marking of DC cables in Republic of Korea ........................................................................... 23

Annex B (informative): Justification of the identification wire colour choices................................. 24

Annex C (informative): Wire colour choice in colour range industrial specification ...................... 25

Annex D (informative): Bibliography ................................................................................................... 27

History .............................................................................................................................................................. 28

IPRs essential or potentially essential to the present document may have been declared to ETSI. The information

pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found

in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in

respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web

Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee

can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web

This final draft ETSI Standard (ES) has been produced by ETSI Technical Committee Environmental Engineering (EE),

In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and

"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of

"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.

The present document has been developed to assist the ICT industry in their development and wider use of DC

powering solutions above the DC voltage range mainly used until now for Telecommunication networks equipment

The present document has been jointly developed by ETSI TC EE and ITU-T Study Group 5 in order to ensure an

equivalent technical content. It is published respectively by ITU as Recommendation ITU-T L.1203 [1] and ETSI

DC has been the main source of power of Telecommunication industry since the very beginning as it is efficient,

This solution is a well proven arrangement that has been used for a century in almost all of the sites in cohabitation with

AC for servers and other buildings services (lighting, facility plugs, lifts, etc.).

It is recognized that DC has many potential applications further to those for ICT and that such applications could benefit

from the standards defined in ITU/ETSI. It is also recognized that further standardization activities on LVDC is now

starting in other standardization organizations such as IEC. Thus ITU-T/ETSI will pursue cooperation with such

ETSI and ITU-T have standardized the widespread DC power interface at inputs of Telecom/ICT equipment used in

Telecom networks, Data centers, and customer sites. The legacy interface for billions of equipment is the SELV voltage

range so called -48V, where the plus pole is grounded as defined for example for interface "A" in ETSI

EN 300 132-2 [7]. Other complementary ETSI standards define a whole DC distribution including earthing and bonding

Higher voltages than 48 V are already widely used in Telecom networks for remote powering of signal repeaters on

copper or optical Telecom transmission lines, with a usual operation in symmetrical voltage up to +/- 200 V in RFT-C

Higher power density of ICT equipment and overall site power in MW for Data centers, have led to the use of higher

voltage firstly in AC single or 3 phases up to 400VAC at the input of servers. The need for resilience, energy efficiency

and cost optimization has pushed the introduction of the up to 400VDC power feeding interface standardized in ETSI

EN 300 132-3-1 [8] and in Recommendation ITU-T L.1200 [2]. This is now available on many servers and network

As there is a progressive introduction of the new DC power interface in cohabitation with existing -48 V and AC

distribution, a new standard ETSI EN 301 605 [10] has been introduced to ensure safety and proper operation especially

in mass bonding of EMC sensitive equipment and correct earthing connection to the building structure earthing

It appears that there is also a strong need for Telecom/Data centers operators, equipment manufacturers or installers and

end customers to clarify the colour and marking of cables in their installations. This would avoid confusion and errors

between the different AC and DC power interfaces and distributions used in the building and inside ICT systems.

Considering the user side, and very long background experience in use of DC of the Telecom sector, the present

document makes Recommendations directly contributing to safety principles laid down in IEC Guide 104 [i.9] and

ISO/IEC Guide 51 [i.10]. It accelerates and encourages the preparation of international standards of cable identification

intended for use by manufacturers, users or certification bodies. The present document makes reference to existing IEC

For useful information, colours of cables inside equipment are considered in annex A as DC is already widely used, e.g.

all the electronic being working only in DC, car and trucks electric circuit being in DC, solar PV power plants, etc.

The scope of the present document is to define common practice for identification of cabling or parts of the DC electric

distribution for the Telecom sites (buildings/rooms) feeding ICT and facilities equipment (power plant, cooling,

This applies to 400VDC cabling for Telecom, ICT equipment and environment equipment using interface defined in

ETSI EN 300 132-3-1 [8] or Recommendation ITU-T L.1200 [2] and avoids confusion between the DC colour and

marking of up to 400VDC distribution and the other power interfaces identification: -48VDC distribution for A

interface, AC and uninterrupted AC given by inverters or UPS used in the building.

• requirements for the colour and identification of separate wires used in DC distribution systems and

installations, and as much as possible inside equipment between A or P interface and end use;

• marking and identification of DC multiwire cables, connectors and any associated equipment for DC power

For DC wires in multiwire cables Recommendations are given for harmonization with separate wire requirements.

Recommendations are given on other distribution items (wires, cables and interconnection items) including the

functional earthing and bonding arrangement for distribution outside and inside equipment to avoid any confusion with

References are either specific (identified by date of publication and/or edition number or version number) or

non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the

Referenced documents which are not found to be publicly available in the expected location might be found at

NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee

The following referenced documents are necessary for the application of the present document.

[1] Recommendation ITU-T L.1203: "Colour and marking identification of up to 400VDC power

[2] Recommendation ITU-T L.1200 (2012): "Direct current power feeding interface up to 400 V at the

[3] IEC 60445 Ed 5.0 2010-08: "Basic and safety principles for man-machine interface, marking and

identification - Identification of equipment terminals, conductor terminations and conductors".

NOTE: IEC DB documents refer to Database of Graphical Symbol. Some are joint with ISO e.g. IEC 60417 and

[7] ETSI EN 300 132-2 (2016): "Environmental Engineering (EE); Power supply interface at the input

to telecommunications and datacom (ICT) equipment; Part 2: Operated by -48 V direct current

[8] ETSI EN 300 132-3-1 (2012): "Environmental Engineering (EE); Power supply interface at the

input to telecommunications and datacom (ICT) equipment; Part 3: Operated by rectified current

source, alternating current source or direct current source up to 400 V; Sub-part 1: Direct current

[9] ETSI EN 300 253 (2015): "Environmental Engineering (EE);Earthing and bonding of ICT

[10] ETSI EN 301 605 (2013): "Environmental Engineering (EE); Earthing and bonding of 400 VDC

References are either specific (identified by date of publication and/or edition number or version number) or

non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the

NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee

The following referenced documents are not necessary for the application of the present document but they assist the

[i.1] ETSI EN 302 099: "Environmental Engineering (EE); Powering of equipment in access network".

[i.2] IEC 60050-195 (1998): "IEC Terminology International Electrotechnical Vocabulary - Part 195:

[i.3] IEC 60050-826 (2004): "International Electrotechnical Vocabulary - Part 826: Electrical

[i.4] British Standard BS 7671 (2008): "Requirements for Electrical Installations. IET Wiring

[i.6] HD 324 S1 (1977): "Colored insulation and bare wire identification package".

[i.7] HD 384.5.514: "Identification, including 514.3: Identification of conductors, now withdrawn".

[i.8] IEC 60364-1 (2005): "Low-voltage electrical installations - Part 1: Fundamental principles,

[i.9] IEC Guide 104: "The preparation of safety publications and the use of basic safety publications

[i.10] ISO/IEC Guide 51: "Safety aspects - Guidelines for their inclusion in standards".

[i.11] IS0 6722 (2006): 2Road vehicles - 60 V and 600 V single-core cables - Dimensions, test methods

[i.12] ISO 2574 (1994): "Flying machine electric cable - Identification marking".

http://www.iso.org/iso/fr/home/store/catalogue_ics/catalogue_detail_ics.htm?ics1=1&ics2=70&ics3=&cs

[i.13] ISO 9247 (1990): "Ground work machine - electric wire and cables -- identification and marking

NOTE: Available at http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=16897.

[i.14] IEC EN 60204-1 (2000): "Safety of machinery -Electrical equipment of machines -Part 1:General

NOTE: IEC/EN 60204-1 is now "Appliance of reference designations on machinery" in accordance with

ISO/IEC/EN 81346 (September 2010) EU Directive 2006/42/EC on machinery (www.81346.com).

[i.15] IEC 60304 (1982): "Standard colours for insulation for low-frequency cables and wires".

NOTE 1: Refered to as "RAL" in the present document, available at http://www.ralcolours.com/.

NOTE 2: RAL is the trade name of a colour matching system supplied by by the RAL gGmbH (RAL non-profit

LLC), which is a subsidiary of the German RAL Institute. This information is given for the convenience

of users of the present document and does not constitute an endorsement by ETSI of the product named.

Equivalent products may be used if they can be shown to lead to the same results.

NOTE 2: Pantone is the trade name of a colour matching system supplied Pantone Inc. This information is given

for the convenience of users of the present document and does not constitute an endorsement by ETSI of

the product named. Equivalent products may be used if they can be shown to lead to the same results.

[i.19] IEC 60446 (withdrawn) (2007): "Basic and safety principles for man-machine interface, marking

[i.20] CCSA YD/T 2378 (2011): "240V Direct Current Power supply system for Telecommunications".

For the purposes of the present document, the following terms and definitions apply:

400VDC: up to 400 Volt Direct Current voltage as defined in Recommendation ITU-T L.1200 [2]

electrical equipment: item used for purposes like generation, conversion, distribution or utilization of electric energy

(e.g. electrical machines, transformers, switch gear and control gear, measuring instruments, wiring systems,

line conductor: AC phase conductor or DC pole conductor (deprecated) conductor which is energized in normal

operation and capable of contributing to the transmission or distribution of electric energy but which is not a neutral

identification: colour, graphical symbol, text in alphanumeric notation located on or adjacent to wire or cable terminals

NOTE: The two letters IT are coding one of the 3 families of electrical distribution where connection to earth is

made through high resistance or impedance device i.e. HRMG in ETSI EN 301 605 [10].

TNS: AC distribution earthing arrangements as defined in IEC 60364-1 [i.8] where earthing and neutral wires are

A (interface) ICT/Telecom equipment -48VDC power interface in ETSI EN 300 132-2 [7]

A3 (interface) ICT/Telecom equipment up to 400VDC power interface in ETSI EN 300 132-3-1 [8]

P ICT equipment up to 400VDC power feeding interface in Recommendation ITU-T L1200 [2]

• Building distribution with A interface (-48V), AC grid and inverter outputs power and A3 or P interface (up to

Figure 1 shows such building where distribution DC and protective earthing-[PE] bonding shall comply with

• Example of power feeding distribution of DC from centralized or decentralized permanent power supply at

Figure 1: DC distribution at building level from DC source to ICT/telecom systems

Figure 2: Example of different DC architectures and distributions at building or technical room level

The identifying colour, graphical symbol or alphanumeric notation shall be located on, or adjacent to the corresponding

There shall be no confusion between the different identification modes i.e. wire insulation colour or coloured sleeve,

For identification of conductors, only colours and code among those permitted in IEC 60757 [4] shall be used (see

The identification of colour is required end to end in the installation for DC from DC source to interface A3 or P and

inside equipment till internal end use inside ICT or facilities equipment (Cooling, Power conversion, Sub distribution,

DC cabling inside power source equipment is recommended to use the same marking and colour as defined in the power

It is accepted to have different identification marking solution along an end to end distribution (insulation colour,

markers, sleeves, symbol and text, etc.) provided they are compliant to the present document. In th