SIST ETS 300 132-2 E1:2006

• Abstract:

  This European Telecommunication Standard (ETS) contains requirements for:; - the output performance of the direct current (dc) power equipment at the interface "A";; - the input of the telecommunications equipment connected to interface "A" powered by dc.; The dc voltage at interface "A" may be derived from the ac primary supply. The dc supply may incorporate a buffer battery. This ETS also makes reference to safety and EMC standards which are in accordance with the relevant European standards. This ETS aims at providing compatibility between the power supply equipment and the power consuming telecommunications equipment, and also between different system blocks connected to the same power supply.; NOTE 1: To ensure satisfactory performance, the connection of telecommunications equipment into installations is subject to the prevailing conditions of that installation and is subject to the agreement of both parties.; NOTE 2: This ETS is applicable only to -48 Vdc power supply interfaces. However, during a transitional period, other dc voltages may be used in existing installations. Annex A gives guidance on working in conjunction with existing -60 Vdc supply systems. The power supply interface, interface "A" of figure 1, is a physical point to which all the requirements are related. This point is situated between the power supply system(s) and the power consuming telecommunications equipment.; NOTE 3: Interface "A" is located at the power terminals of the telecommunications equipment. Subject to the installation preconditions this point may be located at any other point between the power supply system and the telecommunications equipment by mutual agreement of the relevant parties. The requirements at interface "A" apply to: ; - the output of the power supply equipment or power supply installation of telecommunications centres;; - the power supply input of telecommunications equipment installed at telecommunication centres;; - telecommunications equipment, installed in customers premises, whose dc interface "A" is also used by equipment requiring a supply to this specification.; NOTE 4: Normally there is more than one load unit connected to interface "A". In these cases, interface "A" will undergo further restrictions with respect to noise limits or other disturbances specified in subclause 4.8.; NOTE 5: Disturbances on the power supply interface "A" relating to the continuous wave phenomena above 20 kHz is not covered within this ETS. ETS 300 386-1 [3] is applicable for this frequency range.; NOTE 6: The transients to which immunity is specified in this ETS are characterized by a high energy content such that electrical stress may be caused. Fast transients, the effects of which appear mainly as interference, are covered by ETS. ETS 300 386-1 [3] which details the electromagnetic compatibility of telecommunications equipment. ; NOTE 7: An example of a configuration in which the interface "A" is identified is given in annex E.

• Status: Published
• Publication Date: 31-Jan-2006
• ICS: 33.050.01 - Telecommunication terminal equipment in general
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Feb-2006
• Due Date: 01-Feb-2006
• Completion Date: 01-Feb-2006
• Ref Project: ETSI ETS 300 132-2 ed.1 (1996-09) - Equipment Engineering (EE); Power supply interface at the input to telecommunications equipment; Part 2: Operated by direct current (dc)

SIST ETS 300 132-2 E1:2006 is the Slovenian standard identical to ETS 300 132-2 Edition 1 from ETSI. It specifies the power supply interface at the input to telecommunications equipment when the supply is direct current (dc), with interface "A" centered on the -48 Vdc system. The document is used to check that power supply equipment and telecommunications equipment are compatible in voltage, current, noise, safety, earthing and EMC terms.

What does SIST ETS 300 132-2 E1:2006 specify?

SIST ETS 300 132-2 E1:2006 specifies the output performance of dc power equipment at interface "A" and the input behavior of telecommunications equipment connected to that interface. It is written for -48 Vdc power supply interfaces and gives informative guidance for legacy -60 V systems.

The standard treats interface "A" as the physical point between the power supply system and the powered equipment. That matters in practice because the voltage, current, noise and recovery requirements are referenced to that point, so the exact installation arrangement has to be agreed by the parties involved.

The document is organized into clauses on scope, normative references, definitions and abbreviations, requirements, earthing and bonding, electrical safety, and EMC. It also includes informative annexes for legacy supply systems, safety guidance, inrush-current measurement, noise-injection test arrangements, and identification of interface "A".

Annex	What it covers
A	Guidance for existing -60 V systems
B	Safety information and guidance
C	Measuring inrush current and transferring the pulse to the limit chart
D	Test arrangements for injecting electrical noise at interface "A"
E	Identification of interface "A"
F	Bibliography

What are the key requirements of SIST ETS 300 132-2 E1:2006?

SIST ETS 300 132-2 E1:2006 sets the operating envelope for a -48 Vdc telecom power interface and then checks how equipment behaves during normal operation, abnormal voltage, switching events and noise. In practice, the document tells designers and testers what the supply may look like, how much disturbance equipment must survive, and how much noise it may put back onto the power distribution.

Voltage at interface "A"

Clause 4.1 sets the nominal supply voltage at interface "A" to -48 V, with the positive conductor connected to earth. Clause 4.2 gives the normal service range for that supply, and that range is the basis for routine operation and acceptance testing.

Clause 4.3 says equipment shall survive abnormal steady-state voltages without damage, and it shall return to service automatically when the supply comes back into the normal range. In practice, this means the equipment must tolerate supply dips and overvoltages without manual reset or protective device trip-out.

Clause 4.3 also covers short-duration transients. The equipment shall not be damaged, and after the transient it shall continue to function within specification without manual intervention.

Power-supply behavior and protection

Clause 4.4 limits voltage changes due to regulation of the power supply. The equipment must keep operating without data loss or false alarms while the interface voltage rises or falls at the permitted transition rate.

Clause 4.5 requires the supply at interface "A" to be protected by circuit breakers, fuses or similar devices, and it says the inrush energy has to be considered when the supply system is specified. Clause 4.6 limits the current drain during recovery from abnormal service, so the load does not overload the supply while it is returning to normal.

Surge current and conducted noise

Clause 4.7 limits the surge current when interface "A" is connected. The requirement is expressed as a relationship between instantaneous surge current and maximum continuous input current, so equipment makers have to control inrush rather than only steady-state current.

Clause 4.8 sets conducted immunity requirements for noise present at interface "A". It separates narrowband noise from wideband noise, and the measurement methods use spectrum analysis or a psophometer depending on the case. For a buyer or lab, this means the equipment must keep working even when the dc distribution contains low-frequency noise from power converters or shared loads.

Clause 4.9 sets conducted emissions limits for noise sent back from the telecommunications equipment into the supply. That matters because one load can disturb other loads on the same dc distribution, especially where several units share interface "A".

Earthing, safety and EMC

Clause 5 points earthing and bonding in telecommunications centres to ETS 300 253. Clause 6 ties the -48 Vdc interface to the safety requirements for SELV/TNV circuits in EN 60950. Clause 7 points EMC requirements to ETS 300 386-1. Together, these clauses tell the reader that the dc power interface has to be considered together with grounding, electrical safety and electromagnetic compatibility.

What terms does SIST ETS 300 132-2 E1:2006 define?

• interface "A" - The terminals where the power supply is connected to the system block; it is the reference point for the whole standard.
• system block - A functional group of equipment that depends on connection to the same power supply for operation and performance.
• load unit - Power-consuming equipment that is part of a system block.
• normal service voltage range - The steady-state voltage range over which the equipment maintains normal service.
• abnormal voltage range - The steady-state voltage range over which the equipment is not expected to maintain normal service but must survive undamaged.
• EUT - Equipment Under Test, the device placed on the test setup during current and noise measurements.
• LISN - Line Impedance Stabilization Network, used in the test circuits to define the supply impedance during measurements.
• dc - Direct current, used for the power interface and as a suffix on voltage and current values.

Who uses SIST ETS 300 132-2 E1:2006?

Telecommunications equipment manufacturers use this standard to design dc-input equipment that can accept the required voltage range and survive supply disturbances. Power supply designers use it to size protection, account for inrush current and control noise on shared dc distributions.

Network operators, installation engineers and system integrators use it when connecting multiple load units to the same interface "A" in telecommunication centres or customer premises. Test laboratories and quality teams use it for compliance testing of voltage tolerance, recovery behavior, surge current, immunity and emissions.

Which standards are used with SIST ETS 300 132-2 E1:2006?

SIST ETS 300 132-2 E1:2006 is used with a small set of safety, EMC and measurement standards. Its companion part is Part 1, which covers equipment operated by alternating current (ac) derived from direct current (dc) sources.

• EN 60950 - Supplies the safety requirements used in Clause 6 and in the safety guidance annexes.
• ETS 300 253 - Covers earthing and bonding of telecommunication equipment in telecommunication centres.
• ETS 300 386-1 - Provides the EMC framework for disturbances above 20 kHz and for radiated EMC matters.
• ITU-T Recommendation O.41 - Defines the psophometer used for wideband noise measurements.
• ITU-T Recommendations Q.551 to Q.554 - Provide the transmission context cited for noise contribution limits in digital and analogue exchange applications.
• IEC 364-4-41 - Gives protection against electric shock for installations.
• MIL-STD-462 - Is cited with an example of noise-injection measurement arrangements.

What does the SIST ETS 300 132-2 E1:2006 document contain?

The document contains limit charts, voltage ranges and measurement circuits for dc power interface behavior. It also includes figures for the interface "A" concept, inrush current testing, and narrowband and wideband noise measurement at the supply interface.

Annex C gives a practical method for measuring inrush current and transferring the recorded pulse to the limit chart. Annex D shows an example test arrangement for injecting electrical noise at interface "A". Annex E gives a system-level identification example for interface "A", which helps when the physical location of the interface is not obvious in a real installation.

SLOVENSKI STANDARD
01-februar-2006
Inženiring opreme (EE) – Napajalni vmesnik na vhodu v telekomunikacijsko
opremo – 2. del: Obratovanje z enosmerno napetostjo (dc)
Equipment Engineering (EE); Power supply interface at the input to telecommunications
equipment; Part 2: Operated by direct current (dc)
Ta slovenski standard je istoveten z: ETS 300 132-2 Edition 1
ICS:
33.050.01 Telekomunikacijska Telecommunication terminal
terminalska oprema na equipment in general
splošno
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN ETS 300 132-2
TELECOMMUNICATION September 1996
STANDARD
Source: ETSI TC-EE Reference: DE/EE-02001.2
ICS: 33.020
Key words: Power supply
Equipment Engineering (EE);
Power supply interface at the input to
telecommunications equipment;
Part 2: Operated by direct current (dc)
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE
Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: [e-mail]
Tel.: [phone] - Fax: [phone]
Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1996. All rights reserved.

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ETS 300 132-2: September 1996
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.

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ETS 300 132-2: September 1996
Contents
Foreword .5
1 Scope .7
2 Normative references.8
3 Definitions and abbreviations .9
3.1 Definitions .9
3.2 Abbreviations .9
4 Requirements.10
4.1 Nominal value of the supply voltage .10
4.2 Normal service voltage range at interface "A" .10
4.3 Abnormal service voltage range at interface "A".10
4.3.1 Abnormal service voltage under steady-state conditions.10
4.3.2 Recovery from steady state abnormal voltage.10
4.3.3 Short duration voltage transients.10
4.3.4 Recovery from short duration voltage transients.11
4.4 Voltage changes due to the regulation of the power supply .11
4.5 Supply protection at interface "A".11
4.6 Maximum current drain following abnormal service .11
4.7 Surge current on connection of interface "A".11
4.7.1 Limits.11
4.7.2 Measurements.12
4.8 Conducted immunity requirements of the telecommunications equipment at
interface "A" .13
4.8.1 Immunity to narrowband noise .13
4.8.2 Immunity to wideband noise.14
4.9 Conducted emissions requirements of the telecommunications equipment at
interface "A" .15
4.9.1 Emissions of narrowband noise .15
4.9.2 Emissions of wideband noise.16
5 Earthing and bonding .17
6 Electrical safety requirements .17
7 EMC requirements .17
Annex A (informative): 60 V systems .18
dc
Annex B (informative): Information and guide on safety .19
Annex C (informative): Guide for measuring inrush current and for transferring the recorded pulses
onto the limit chart .20
C.1 Measurement .20
C.2 Pulse waveform transformation.20
Annex D (informative): Test arrangements for the injection of electrical noise at interface "A" .22
Annex E (informative): Identification of interface "A".23
Annex F (informative): Bibliography.24

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ETS 300 132-2: September 1996
History. 25

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ETS 300 132-2: September 1996
Foreword
This European Telecommunication Standard (ETS) has been produced by the Equipment Engineering
(EE) Technical Committee of the European Telecommunications Standards Institute (ETSI).
This ETS concerns the requirements for the interface between telecommunications equipment and its
power supply, and includes requirements relating to its stability and measurement. References are also
made to the safety aspects, in various IEC and CENELEC documents which are normative to this ETS.
Various other references and detailed measurement and test arrangements are contained in informative
annexes.
This ETS consists of 2 parts as follows:
Part 1: "Operated by alternating current (ac) derived from direct current (dc) sources"
Part 2: "Operated by direct current (dc)"
Transposition dates
Date of adoption of this ETS: 16 August 1996
Date of latest announcement of this ETS (doa): 31 December 1996
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 30 June 1997
Date of withdrawal of any conflicting National Standard (dow): 30 June 1997

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ETS 300 132-2: September 1996
Blank page
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ETS 300 132-2: September 1996
1 Scope
This European Telecommunication Standard (ETS) contains requirements for:
- the output performance of the direct current (dc) power equipment at the interface "A";
- the input of the telecommunications equipment connected to interface "A" powered by dc.
The dc voltage at interface "A" may be derived from the ac primary supply. The dc supply may incorporate
a buffer battery.
This ETS also makes reference to safety and EMC standards which are in accordance with the relevant
European standards.
This ETS aims at providing compatibility between the power supply equipment and the power consuming
telecommunications equipment, and also between different system blocks connected to the same power
supply.
NOTE 1: To ensure satisfactory performance, the connection of telecommunications equipment
into installations is subject to the prevailing conditions of that installation and is subject
to the agreement of both parties.
NOTE 2: This ETS is applicable only to -48 V power supply interfaces. However, during a
dc
transitional period, other dc voltages may be used in existing installations. Annex A
gives guidance on working in conjunction with existing -60 V supply systems.
dc
The power supply interface, interface "A" of figure 1, is a physical point to which all the requirements are
related. This point is situated between the power supply system(s) and the power consuming
telecommunications equipment.
NOTE 3: Interface "A" is located at the power terminals of the telecommunications equipment.
Subject to the installation preconditions this point may be located at any other point
between the power supply system and the telecommunications equipment by mutual
agreement of the relevant parties.
The requirements at interface "A" apply to:
- the output of the power supply equipment or power supply installation of telecommunications
centres;
- the power supply input of telecommunications equipment installed at telecommunication centres;
- telecommunications equipment, installed in customers premises, whose dc interface "A" is also
used by equipment requiring a supply to this specification.
NOTE 4: Normally there is more than one load unit connected to interface "A". In these cases,
interface "A" will undergo further restrictions with respect to noise limits or other
disturbances specified in subclause 4.8.
NOTE 5: Disturbances on the power supply interface "A" relating to the continuous wave
phenomena above 20 kHz is not covered within this ETS. ETS 300 386-1 [3] is
applicable for this frequency range.
NOTE 6: The transients to which immunity is specified in this ETS are characterized by a high
energy content such that electrical stress may be caused. Fast transients, the effects
of which appear mainly as interference, are covered by ETS. ETS 300 386-1 [3] which
details the electromagnetic compatibility of telecommunications equipment.
NOTE 7: An example of a configuration in which the interface "A" is identified is given in
annex E.
Page 8
ETS 300 132-2: September 1996
telecommunications
equipment
DC power supply conductors
system block
interface A
Figure 1: General identification of the power interface "A"
The purpose of this ETS is:
- to use a power supply system with the same characteristics for all telecommunications equipment
defined in the area of application;
- to facilitate interworking of different (types of) load units;
- to facilitate the standardization of telecommunications equipment;
- to facilitate the installation, operation and maintenance in the same network of equipment and
telecommunications systems from different origins.
2 Normative references
This ETS incorporates by dated and 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 ETS only when incorporated in it by amendment or revision. For undated references the latest
edition of the publication referred to applies.
[1] EN 60950: "Safety of information technology equipment, including electrical
business equipment".
[2] ETS 300 253: "Equipment Engineering (EE); Earthing and bonding of
telecommunication equipment in telecommunication centres".
[3] ETS 300 386-1 (1994): "Equipment Engineering (EE); Public telecommunication
network equipment; Electro-Magnetic Compatibility (EMC) requirements;
Part 1: Product family overview, compliance criteria and test levels".
[4] ITU-T Recommendation O.41: "Psophometer for use on telephone-type
circuits".
[5] ITU-T Recommendation Q.551: "Transmission characteristics of digital
exchanges".
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ETS 300 132-2: September 1996
[6] ITU-T Recommendation Q.552: "Transmission characteristics at 2-wire
analogue interfaces of digital exchange".
[7] ITU-T Recommendation Q.553: "Transmission characteristics at 4-wire
analogue interfaces of a digital exchange".
[8] ITU-T Recommendation Q.554: "Transmission characteristics at digital
interfaces of a digital exchange".
[9] IEC 364-4-41 (1982): "Electrical installations of buildings - Part 4: Protection for
safety - Chapter 41: Protection against electric shock".
[10] US Department of Defense MIL-STD-462: "Electromagnetic interference
characteristics, measurement of".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of this ETS, the following definitions apply:
abnormal voltage range: The range of steady-state voltage over which the equipment will not be
expected to maintain normal service but will survive undamaged.
customer premises: Any location which is the sole responsibility of the customer.
interface "A": The terminals at which the power supply is connected to the system block (see figure 1).
NOTE 1: This is a functional definition and not an exact depiction of the physical location.
load unit: Power consuming equipment, that is part of a system block.
nominal voltage value: The nominal value of the voltage that designates the type of supply.
normal service voltage range: The range of steady-state voltages over which the equipment will
maintain normal service.
normal service: The service mode where telecommunications equipment operates within its
specification.
power supply: A power source to which telecommunications equipment is intended to be connected.
system block: A functional group of equipment depending for its operation and performance on its
connection to the same power supply.
NOTE 2: A system block may consist of equipment or a functional group of equipment. Different
examples of configurations at interface "A" are given in annex E.
telecommunication centre: Any location where telecommunications equipment is installed and which is
the sole responsibility of the operator.
3.2 Abbreviations
For the purposes of this ETS, the following abbreviations apply:
dc direct current (also when used as a suffix to units of measurement)
EUT Equipment Under Test
I maximum current (see subclause 4.7.1)
m
I nominal current
nom
I instantaneous surge current (see subclause 4.7.1)
t
Page 10
ETS 300 132-2: September 1996
L inductance of inductive element of LISN
LISN Line Impedance Stabilization Network
... (subscripted letter following unit) psophometrically weighted
p
R resistance of resistive element of LISN
rms root mean square (also when used as a suffix to units of measurement)
t time
Z capacitive impedance of immunity measurement circuit
c
Z resistive impedance of immunity measurement circuit
m
4 Requirements
4.1 Nominal value of the supply voltage
The nominal value of the voltage at interface "A" shall be -48 V (positive conductor is connected to
dc
earth).
NOTE 1: In most cases the voltage of interface "A" will be complemented by a 24 cell lead-acid
battery.
NOTE 2: During a transitional period, other dc voltages may be used in existing installations.
Annex A gives guidance on merging equipment with existing -60 V supply systems.
dc
4.2 Normal service voltage range at interface "A"
The normal service voltage range for the -48 V nominal supply at interface "A" shall be -40,5 to -57,0 V .
dc dc
NOTE 1: The voltages specified are measured at interface "A". It should be n
...