SIST ETS 300 450 E1:2004
(Main)Business TeleCommunications (BTC); Ordinary and Special quality voice bandwidth 2-wire analogue leased lines (A2O and A2S); Terminal equipment interface
General Information
- Abstract
Specification of the terminal equipment side of the interface and test procedures for compliance.
- Status
- Published
- Publication Date
- 30-Sep-2004
- Technical Committee
- BTC - Business telecommunications
- Current Stage
- 6060 - National Implementation/Publication (Adopted Project)
- Start Date
- 01-Oct-2004
- Due Date
- 01-Oct-2004
- Completion Date
- 01-Oct-2004
- Mandate
- T-147-2
Overview
SIST ETS 300 450 E1:2004 is a Slovenian standard that specifies the physical, electrical, and test requirements for the terminal equipment interface of 2-wire analogue leased lines used in business telecommunications (BTC). This standard addresses both ordinary (A2O) and special (A2S) quality voice bandwidth leased lines, providing clear criteria for ensuring interoperability and compliance at the interface between terminal equipment and network termination points (NTP) of Open Network Provision (ONP) services, as defined by ETSI standards.
Key Topics
- Terminal Equipment Interface: Outlines the required types of physical connections (such as standardized plugs and terminal blocks) for connecting customer terminal equipment to analogue leased lines.
- Physical and Electrical Characteristics: Details requirements for aspects such as return loss, longitudinal conversion loss, transmission signal categories, and maximum output levels to maintain transmission quality and prevent network disturbance.
- Test Methods for Compliance: Specifies methodologies for verifying interface compliance with criteria such as:
- Return loss (minimizing signal reflection)
- Longitudinal conversion loss (resistance to unwanted signals)
- Loudness rating for voice equipment
- Maximum mean and instantaneous power levels
- Power feeding restrictions to avoid unintended network powering
- Scope Limitations: Focuses on the terminal side interface and does not regulate customer internal wiring or installation practices beyond the NTP.
- Safety and EMC: Requires compliance with general safety standards for connection to telecommunication networks. Electromagnetic compatibility (EMC) requirements are referenced but addressed in broader regulatory frameworks.
Applications
The standard is essential for manufacturers, integrators, and network operators who design or deploy terminal equipment for use with analogue leased line services in business environments. Its practical value includes:
- Ensuring Compatibility: Promotes seamless interconnection across different vendors’ terminal equipment and telecom networks across Europe, supporting open network access as mandated by EU ONP directives.
- Improving Service Quality: Ensures that voice and data transmission over leased lines remain free from interference, excessive signal loss, or distortion, making it crucial for services like telephony, voice mail, modems, and analogue data links.
- Regulatory Compliance: Aids equipment suppliers and telecom operators in meeting EU requirements for leased lines, providing a foundation for product certification and market access.
- Harmonizing Technical Interfaces: Supports the development of interoperable communications infrastructure in international and cross-border business applications.
Related Standards
- SIST ETS 300 448: Specifies connection characteristics and network interface for ordinary quality voice bandwidth 2-wire analogue leased lines (A2O).
- SIST ETS 300 449: Covers special quality voice bandwidth 2-wire analogue leased lines (A2S) and their network interface presentation.
- EN 28877: Defines ISDN basic access interface connectors and contact assignments.
- EN 60950: Addresses general safety for information technology and telecommunication equipment.
- ITU-T Recommendations (e.g., P.56, P.64): Referenced for speech level measurement and loudness calculations.
Practical Value
Adopting SIST ETS 300 450 E1:2004 helps organizations to:
- Minimize operational issues at the network boundary
- Ensure stable and high-quality voice/data services for business users
- Facilitate market acceptance of terminal equipment by demonstrating compliance with harmonized European standards
- Reduce costly field engineering and troubleshooting related to interface incompatibility
Keywords
business telecommunications, 2-wire analogue leased lines, terminal equipment interface, A2O, A2S, voice bandwidth, ONP, leased line compliance, interoperability, network termination point, test procedures, SIST standards, ETSI, voice quality.
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Frequently Asked Questions
SIST ETS 300 450 E1:2004 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Business TeleCommunications (BTC); Ordinary and Special quality voice bandwidth 2-wire analogue leased lines (A2O and A2S); Terminal equipment interface". This standard covers: Specification of the terminal equipment side of the interface and test procedures for compliance.
Specification of the terminal equipment side of the interface and test procedures for compliance.
SIST ETS 300 450 E1:2004 is classified under the following ICS (International Classification for Standards) categories: 33.040.50 - Lines, connections and circuits. The ICS classification helps identify the subject area and facilitates finding related standards.
SIST ETS 300 450 E1:2004 is associated with the following European legislation: Standardization Mandates: T-147-2. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
SIST ETS 300 450 E1:2004 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-oktober-2004
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SDVRYQRãLULQRWHUQDYDGQRLQSRVHEQRNDNRYRVWMR$2LQ$69PHVQLN
WHUPLQDOVNHRSUHPH
Business TeleCommunications (BTC); Ordinary and Special quality voice bandwidth 2-
wire analogue leased lines (A2O and A2S); Terminal equipment interface
Ta slovenski standard je istoveten z: ETS 300 450 Edition 1
ICS:
33.040.50 Vodi, zveze in tokokrogi Lines, connections and
circuits
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN ETS 300 450
TELECOMMUNICATION February 1996
STANDARD
Source: ETSI TC-BTC Reference: DE/BTC-02028
ICS: 33.020
ONP, leased line, A2O, A2S
Key words:
Business TeleCommunications (BTC);
Ordinary and Special quality voice bandwidth
2-wire analogue leased lines (A2O and A2S);
Terminal equipment interface
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
F-06921 Sophia Antipolis CEDEX - FRANCE
Postal address:
650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
Office address:
c=fr, a=atlas, p=etsi, s=secretariat - secretariat@etsi.fr
X.400: Internet:
Tel.: +33 92 94 42 00 - Fax: +33 93 65 47 16
*
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 300 450: February 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 300 450: February 1996
Contents
Foreword .5
Introduction.5
1 Scope .7
2 Normative references.7
3 Definitions and abbreviations .7
3.1 Definitions .7
3.2 Abbreviations .8
4 Requirements.8
4.1 Physical characteristics.8
4.2 Electrical characteristics .9
4.2.1 Return loss .9
4.2.2 Longitudinal conversion loss .9
4.2.3 Transmission signals.10
4.2.3.1 Equipment with an acoustic input .10
4.2.3.1.1 Sending Loudness Rating (SLR) .10
4.2.3.2 Equipment with internally generated electrical signals .11
4.2.3.2.1 Maximum mean power .11
4.2.3.2.2 Maximum instantaneous power (peak
voltage) .11
4.2.3.2.3 Maximum power in a 10 Hz bandwidth.11
4.2.3.3 Equipment with an electrical input .12
4.2.4 Maximum sending power above 4,3 kHz .12
4.2.5 Power feeding .13
4.3 Safety.13
4.4 ElectroMagnetic Compatibility (EMC) .13
Annex A (normative): Test methods.15
A.1 General.15
A.1.1 Equipment connection .15
A.1.2 Reference impedance.15
A.1.3 Non-reactive termination.15
A.2 Test methods .16
A.2.1 Return loss.16
A.2.2 Longitudinal conversion loss.17
A.2.3 Sending Loudness Rating.18
A.2.4 Maximum mean power .19
A.2.5 Maximum instantaneous power (peak voltage) .20
A.2.6 Maximum power in a 10 Hz bandwidth.21
A.2.7 Maximum sending power above 4,3 kHz.22
A.2.8 Power feeding.23
Annex B (informative): Bibliography.24
History.25
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ETS 300 450: February 1996
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ETS 300 450: February 1996
Foreword
This European Telecommunication Standard (ETS) has been produced by the Business
TeleCommunications (BTC) Technical Committee of the European Telecommunications Standards
Institute (ETSI).
This ETS resulted from a mandate from the Commission of the European Community (CEC) to provide
harmonized standards for the support of the Directive on Open Network Provision (ONP) of leased lines
(92/44/EEC).
There are two other standards directly related to this ETS:
ETS 300 448: "Business TeleCommunications (BTC); Ordinary quality voice bandwidth 2-wire
analogue leased line (A2O); Connection characteristics and network interface
presentation".
ETS 300 449: "Business TeleCommunications (BTC); Special quality voice bandwidth 2-wire
analogue leased line (A2S); Connection characteristics and network interface
presentation".
This ETS is based on information from ITU-T Recommendations and ETSI publications and the relevant
documents are quoted where appropriate.
Transposition dates
Date of adoption of this ETS: 2 February 1996
Date of latest announcement of this ETS (doa): 31 May 1996
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 30 November 1996
Date of withdrawal of any conflicting National Standard (dow): 30 November 1996
Introduction
The Council Directive on the application of ONP to leased lines (92/44/EEC) concerns the harmonization
of conditions for open and efficient access to, and use of, the leased lines provided over public
telecommunications networks, and the availability throughout the European Union (EU) of a minimum set
of leased lines with harmonized technical characteristics.
The consequence of the Directive is that telecommunications organizations within the EU shall make
available a set of leased lines within and between points in these countries with specified connection
characteristics and specified interfaces.
Two classes of standard will be used for the interfaces of terminal equipment designed for connection to
the ONP leased lines. ETSs, which are voluntary, give the full technical specifications for these interfaces,
whereas Technical Basis for Regulations (TBRs) give the essential requirements under the Second Phase
Directive (91/263/EEC) for attachment to the leased lines. This standard, which is an ETS, belongs to the
first category. The TBR (prTBR 15) is a subset of this corresponding ETS.
CCITT Recommendations M.1020 (1988) and M.1040 (1988) are used as the basis for the leased line
standards to which this terminal equipment interface relates.
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ETS 300 450: February 1996
Blank page
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ETS 300 450: February 1996
1 Scope
This European Telecommunication Standard (ETS) specifies the full physical and electrical characteristics
and corresponding test principles for a terminal equipment interface for connection to the network
termination points of Open Network Provision (ONP) ordinary quality or special quality voice bandwidth
2-wire analogue leased lines defined by ETS 300 448 and ETS 300 449. This ETS is not written for
regulatory purposes.
This ETS is written only to ensure that the interface of the terminal equipment is compatible with the ONP
ordinary quality or special quality voice bandwidth 2-wire analogue leased line. It is applicable to all
interfaces designed for connection to these leased lines, however in the cases of apparatus that carries a
particular service, of complex apparatus and of apparatus in private networks, other ETSs may apply in
addition to this ETS.
Customer premises wiring and installation between the terminal equipment and the NTP are outside the
scope of this ETS.
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 28877 (1989): "Information processing systems - Interface connector and
contact assignments for ISDN basic access interface located at reference points
S and T".
[2] EN 60950 (1992): "Safety of information technology equipment including
electrical business equipment".
[3] ITU-T Recommendation P.56 (1993): "Objective measurement of active speech
level".
[4] ITU-T Recommendation P.64 (1993): "Determination of sensitivity/ frequency
characteristics of local telephone systems to permit calculation of their loudness
ratings".
NOTE: This ETS also contains a number of informative references which have been included
to indicate the sources from which material has been derived, hence they do not have
an associated normative reference number. Details of these publications are given in
annex B. In some cases, the same publication may have been referenced in both a
normative and an informative manner.
3 Definitions and abbreviations
3.1 Definitions
For the purposes of this ETS, the following definitions apply:
leased lines: The telecommunications facilities provided by a public telecommunication network that
provide defined transmission characteristics between network termination points and that do not include
switching functions that the user can control, (e.g. on-demand switching).
Network Termination Point (NTP): All physical connections and their technical access specifications
which form part of the public telecommunications network and are necessary for access to and efficient
communication through that public network.
reference impedance Z : This is a complex impedance made up of a resistance of 270 Ω in series with
R
a parallel combination of 750 Ω and 150 nF. See also subclause A.1.2.
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ETS 300 450: February 1996
terminal equipment: Equipment intended to be connected to the public telecommunication network; i.e.:
- to be connected directly to the termination of a public telecommunication network; or
- to interwork with a public telecommunication network being connected directly or indirectly to the
termination of a public telecommunication network,
in order to send, process, or receive information.
voice bandwidth: The band of frequencies over the range 300 Hz to 3 400 Hz.
3.2 Abbreviations
For the purposes of this ETS, the following abbreviations apply:
a Return loss in dB
dc direct current
DTMF Dual Tone Multi-Frequency
EMC ElectroMagnetic Compatibility
NTP Network Termination Point
ONP Open Network Provision
p Sound pressure at the mouth reference point (used in the calculation of SLR)
m
rms root mean square
SLR Sending Loudness Rating
S Sending sensitivity (used in the calculation of SLR)
mJ
S Sending sensitivity at frequency f (used in the calculation of SLR)
mJn n
TNV Telecommunications Network Voltage (see EN 60950 [2], subclause 3.4)
W
Sending weighting factor (used in the calculation of SLR)
sn
Z Reference impedance
R
Z Termination impedance
T
4 Requirements
4.1 Physical characteristics
Requirement: The terminal equipment shall provide one or more of the following connection methods:
a) an 8-contact plug of the type specified in EN 28877 [1] with contact assignments as specified in
table 1;
b) a set of connection contacts (e.g. an insulation displacement connector or screw terminal block) to
which solid conductors with diameters in the range 0,4 to 0,6 mm may be connected;
c) a wiring arrangement connected by any means to the terminal equipment, with unterminated solid
wire conductors with diameters in the range 0,4 to 0,6 mm at the distant end from the terminal
equipment.
Where a) and c) are provided, these may be detachable by the user such that only one is connected to the
terminal equipment at any one time.
NOTE: The normal presentation of the leased line is by means of a socket.
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ETS 300 450: February 1996
Table 1: Contact assignments
Contact number terminal equipment
1 Unused
2 Unused
3 Unused
4 & 5 Pair
6 Unused
7 Unused
8 Unused
Test: There shall be a visual inspection that one or more of the connection methods are provided. The
contact assignments and connection methods are tested indirectly through the tests in annex A.
4.2 Electrical characteristics
The requirements of subclause 4.2 apply only in the intended operating state of the terminal equipment.
4.2.1 Return loss
Requirement: The return loss of the impedance presented by the terminal equipment interface with
respect to the reference impedance, in the frequency range 200 Hz to 4 000 Hz, shall be greater than or
equal to 8 dB throughout the range when tested using a stimulus signal at a voltage equivalent to that of a
signal power of -9 dBm at 1 020 Hz.
Test: The test shall be conducted according to subclause A.2.1.
4.2.2 Longitudinal conversion loss
Requirement: The longitudinal conversion loss of the terminal equipment interface shall be greater than
or equal to the values given in table 2 and figure 1.
NOTE: The longitudinal conversion loss specifies the unwanted transverse signal detected by
the terminal equipment when a longitudinal signal is applied equally to the terminals of
the interface. Certain networks may have high longitudinal signal levels (e.g. 65 V root
mean square (rms)); in this case, a higher longitudinal conversion loss may be
necessary to ensure adequate operation of the terminal equipment.
Table 2: Longitudinal conversion loss, minimum values
Frequency range Minimum value
300 Hz to 600 Hz 40 dB
600 Hz to 3 400 Hz 46 dB
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ETS 300 450: February 1996
Longitudinal conversion loss dB
300 400 500 600 1000 2000 3400 5000
Frequency Hz
Figure 1: Longitudinal conversion loss, minimum values
Test: The test shall be conducted according to subclause A.2.2.
4.2.3 Transmission signals
The source and nature of the output signal from the terminal equipment interface can be classified in
several different ways thus dividing the terminal equipments into several non-exclusive categories. One
type of terminal equipment may therefore need to be treated as a member of more than one of the
categories. For the purposes of this ETS, the general categories requiring identification are defined as
follows:
a) any terminal equipment where the output signal is derived in real time from an integral
acoustic interface. See subclause 4.2.3.1;
b) any terminal equipment where the output signal is generated electrically within the terminal
equipment. See subclause 4.2.3.2;
c) any through connecting terminal equipment where the output signal is derived from another
electrical interface. See subclause 4.2.3.3.
NOTE: Terminal equipments may belong to more than one category. A telephone may be in
both category a) for telephony and category b) for the generation of Dual Tone Multi-
Frequency (DTMF) tones. A function for generating synthetic or recorded speech or
music, such as is found in answering machines or voice mail, is included in
category b).
4.2.3.1 Equipment with an acoustic input
4.2.3.1.1 Sending Loudness Rating (SLR)
Requirement: The minimum SLR of the terminal equipment, when terminated with the reference
impedance Z , shall be greater than or equal to -5 dB.
R
NOTE: The minimum SLR value of -5 dB refers to the actual measured value rather than the
nominal value, i.e. there is no tolerance on the specified value, and has been specified
to ensure no harm to the network. It is recommended that for normal operation, the
SLR should be greater than or equal to -2 dB.
Test: The test shall be conducted according to subclause A.2.3.
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ETS 300 450: February 1996
4.2.3.2 Equipment with internally generated electrical signals
4.2.3.2.1 Maximum mean power
Requirement: The mean power level in the frequency range 200 Hz to 3 800 Hz in any one minute period
shall be not greater than -9 dBm when the terminal equipment interface is terminated with the reference
impedance Z .
R
Test: The test shall be conducted according to subclause A.2.4.
4.2.3.2.2 Maximum instantaneous power (peak voltage)
The maximum instantaneous power is expressed in terms of the peak voltage.
Requirement: The peak voltage from the terminal equipment interface shall not be greater than 2,0 V
over the frequency range 200 Hz to 3 800 Hz when the terminal equipment interface is terminated with the
reference impedance Z .
R
Test: The test shall be conducted according to subclause A.2.5.
4.2.3.2.3 Maximum power in a 10 Hz bandwidth
Requirement: The maximum power within a 10 Hz bandwidth centred at any frequency within the
frequency band 0 Hz to 4 300 Hz, and wholly contained within that frequency band, shall not exceed the
limits given in table 3 and figure 2 when the terminal equipment interface is terminated with the reference
impedance Z .
R
Exceptionally, when sending DTMF tones, the maximum power in a 10 Hz bandwidth between the
frequencies 1 200 Hz and 1 700 Hz shall not exceed -3 dBm.
NOTE: Generally, DTMF tones will have a duty cycle of 50 % or less.
Table 3: Maximum power in a 10 Hz bandwidth
Points Frequency range kHz Maximum sending power dBm
(see fig. 2)
0,0 -33
A 0,03 -33
B 0,1 -16
C 0,3 -6
D 3,4 -6
E 3,8 -15
F 4,3 -44
NOTE: Limits for intermediate frequencies are found by drawing a
straight line between the break points in table 3 on a
logarithmic(frequency) - linear(dB) scale.
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ETS 300 450: February 1996
0 0,03 0,1 0,3 3,4 3,8 4,3
Frequency kHz
-6
CD
-10
-15
-16
E
B
-20
-30
-33
A
-40
F
-44
-50
Measurement bandwidth 10 Hz
Not to scale
Maximum
power dBm
Figure 2: Maximum power in a 10 Hz bandwidth
Test: The test shall be conducted according to subclause A.2.6.
4.2.3.3 Equipment with an electrical input
There is no requirement on the level of the output signal in the frequency range 0 Hz to 4 300 Hz where
the ou
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