Teleprotection equipment of power systems - Performance and testing -- Part 1: Command systems

EN following parallel vote * Supersedes HD 543.1 S1

Schutzsignal-Übertragungseinrichtungen für Energieversorgungsnetze - Leistungsmerkmale und Prüfungen -- Teil 1: Systeme mit Übertragung von Befehlen

Matériels de téléprotection des réseaux d'énergie électrique - Performances et essais -- Partie 1: Systèmes de commande

S'applique aux matériels de téléprotection à bande étroite (max. 4 kHz) à signal unique ou multiple. S'applique également aux matériels à fréquences vocales utilisés avec divers systèmes de télécommunications, tels que courant porteur sur ligne d'énergie, liaisons radioélectriques, circuits loués et câbles concédés aux privés. Etablit les prescriptions pour les performances et les méthodes d'essai des voies utilisées par les signaux de transmission d'information de commande nécessaires aux dispositifs de protection des réseaux d'énergie électrique et donne la terminologie s'y rapportant.

Teleprotection eqiupment of power systems - Performance and testing - Part 1: Command systems (IEC 60834-1:1999)

General Information

Status
Published
Publication Date
31-Jan-2001
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Feb-2001
Due Date
01-Feb-2001
Completion Date
01-Feb-2001

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SLOVENSKI STANDARD
SIST EN 60834-1:2001
01-februar-2001
1DGRPHãþD
SIST HD 543.1 S1:1997
Teleprotection eqiupment of power systems - Performance and testing - Part 1:
Command systems (IEC 60834-1:1999)
Teleprotection equipment of power systems - Performance and testing -- Part 1:
Command systems
Schutzsignal-Übertragungseinrichtungen für Energieversorgungsnetze -
Leistungsmerkmale und Prüfungen -- Teil 1: Systeme mit Übertragung von Befehlen

Matériels de téléprotection des réseaux d'énergie électrique - Performances et essais --

Partie 1: Systèmes de commande
Ta slovenski standard je istoveten z: EN 60834-1:1999
ICS:
29.240.20 Daljnovodi Power transmission and
distribution lines
SIST EN 60834-1:2001 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 60834-1:2001
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SIST EN 60834-1:2001
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SIST EN 60834-1:2001
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SIST EN 60834-1:2001
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SIST EN 60834-1:2001
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SIST EN 60834-1:2001
NORME CEI
INTERNATIONALE IEC
60834-1
INTERNATIONAL
Deuxième édition
STANDARD
Second edition
1999-10
Matériels de téléprotection des
réseaux d'énergie électrique –
Performances et essais –
Partie 1:
Systèmes de commande
Teleprotection equipment of power systems –
Performance and testing –
Part 1:
Command systems
 IEC 1999 Droits de reproduction réservés  Copyright - all rights reserved

Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in

utilisée sous quelque forme que ce soit et par aucun procédé, any form or by any means, electronic or mechanical,

électronique ou mécanique, y compris la photo-copie et les including photocopying and microfilm, without permission in

microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http://www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale
PRICE CODE
International Electrotechnical Commission
Pour prix, voir catalogue en vigueur
For price, see current catalogue
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SIST EN 60834-1:2001
60834-1  IEC:1999 – 3 –
CONTENTS
Page

FOREWORD .......................................................................................................................... 7

Clause

1 General............................................................................................................................ 9

1.1 Scope ..................................................................................................................... 9

1.2 Normative references.............................................................................................. 9

1.3 Service conditions................................................................................................. 11

1.4 Telecommunication system used........................................................................... 13

1.5 Definitions............................................................................................................. 15

2 Characteristics of command type teleprotection systems ................................................ 23

2.1 Types of teleprotection command schemes ........................................................... 23

2.2 Overall operating time of teleprotection systems

(telecommunication circuit included)...................................................................... 23

2.3 Transmission times (telecommunication circuit excluded) ...................................... 23

2.4 Security ................................................................................................................ 25

2.5 Dependability ........................................................................................................ 27

2.6 Nominal frequency band or bit rate ........................................................................ 29

2.7 Nominal impedance............................................................................................... 29

2.8 Guard signals/Command signals ........................................................................... 29

2.9 Levels of guard signals (analogue systems only) ................................................... 29

2.10 Levels of command signals (analogue systems only) ............................................. 29

3 Requirements for command type teleprotection systems................................................. 31

3.1 General equipment interface requirements ............................................................ 31

3.2 Specific power supply requirements....................................................................... 37

3.3 Teleprotection system performance requirements.................................................. 39

4 Methods for performance testing .................................................................................... 47

4.1 General equipment interface tests ......................................................................... 47

4.2 Specific power supply tests ................................................................................... 49

4.3 Teleprotection system performance tests .............................................................. 51

Annex A (informative) Teleprotection system performance tests.......................................... 99

Annex B (informative) Binary symmetric channel (BSC) model .......................................... 107

Annex C (informative) Example of a security analysis for a simple protocol ....................... 109

Figure 1 – Voice frequency configuration .............................................................................. 69

Figure 2 – Power line carrier frequency configuration ............................................................ 69

Figure 3 – Directly connected digital teleprotection (example) ............................................... 69

Figure 4 – Digital teleprotection connected via a multiplexed communication system ............. 69

Figure 5 – Fundamental terms on protection and teleprotection............................................. 71

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SIST EN 60834-1:2001
60834-1  IEC:1999 – 5 –
Page

Figure 6 – Typical operating times for protection systems incorporating teleprotection........... 73

Figure 7 – Test circuit for testing power supply interruptions ................................................. 75

Figure 8 – Test circuit for LF disturbance emission measurement.......................................... 75

Figure 9 – Examples of the probability of missing command versus signal-to-noise ratio ....... 77

Figure 10 – Test set-up for dependability measurement (analogue teleprotection) ................. 79

Figure 11 – Test set-up for dependability measurement (digital teleprotection) ...................... 79

Figure 12 – Test set-up for security measurement (analogue teleprotection).......................... 81

Figure 13 – Test set-up for security measurement (digital teleprotection) .............................. 81

Figure 14 – Examples of probability of unwanted commands versus signal-to-noise ratio

for 200 Bd channel ............................................................................................................. .. 83

Figure 15 – Test set-up for measuring transmission time....................................................... 85

Figure 16 – Test set-up for measuring interference by discrete frequencies........................... 85

Figure 17 – Test set-up for measuring interference by frequency deviation ............................ 87

Figure 18 – Frequency deviation versus time for test set-up in figure 17 ................................ 87

Figure 19 – Test set-up for recovery time measurement for digital teleprotection ................... 89

Figure 20 – Test set-up for recovery time measurement for analogue teleprotection .............. 89

Figure 21 – Performance guidance figures for various teleprotection schemes ...................... 91

Figure 22 – Example of dependability curves for digital teleprotection.................................... 93

Figure 23 – Example of security curve for digital teleprotection.............................................. 95

Figure 24 – Test set-up for measuring jitter at the output of a digital

teleprotection transmitter ......................................................................................................97

Figure 25 – Jitter mask for testing jitter at the input of a digital teleprotection receiver ........... 97

Figure A.1 – Graph showing the uncertainty of probability for a confidence level

of 95 % for various values of E and N ................................................................................. 103

Figure A.2 – Examples of probability of unwanted commands versus signal-to-noise ratio

for a 200 Bd channel........................................................................................................... 105

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SIST EN 60834-1:2001
60834-1  IEC:1999 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
TELEPROTECTION EQUIPMENT OF POWER SYSTEMS –
PERFORMANCE AND TESTING –
Part 1: Command systems
FOREWORD

1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising

all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote

international co-operation on all questions concerning standardization in the electrical and electronic fields. To

this end and in addition to other activities, the IEC publishes International Standards. Their preparation is

entrusted to technical committees; any IEC National Committee interested in the subject dealt with may

participate in this preparatory work. International, governmental and non-governmental organizations liaising

with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization

for Standardization (ISO) in accordance with conditions determined by agreement between the two

organizations.

2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an

international consensus of opinion on the relevant subjects since each technical committee has representation

from all interested National Committees.

3) The documents produced have the form of recommendations for international use and are published in the form

of standards, technical reports or guides and they are accepted by the National Committees in that sense.

4) In order to promote international unification, IEC National Committees undertake to apply IEC International

Standards transparently to the maximum extent possible in their national and regional standards. Any

divergence between the IEC Standard and the corresponding national or regional standard shall be clearly

indicated in the latter.

5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any

equipment declared to be in conformity with one of its standards.

6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject

of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 60834-1 has been prepared by IEC technical committee 57: Power

system control and associated communications.
This second edition cancels and replaces the first edition published in 1988.
The text of this standard is based on the following documents:
FDIS Report on voting
57/406/FDIS 57/425/RVD

Full information on the voting for the approval of this standard can be found in the report on

voting indicated in the above table.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 3.

Annexes A, B and C are for information only.

The committee has decided that this publication remains valid until 2004. At this date, in

accordance with the committee’s decision, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
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SIST EN 60834-1:2001
60834-1  IEC:1999 – 9 –
TELEPROTECTION EQUIPMENT OF POWER SYSTEMS –
PERFORMANCE AND TESTING –
Part 1: Command systems
1 General
1.1 Scope

This part of IEC 60834 applies to teleprotection command systems used to convey command

information, generally in conjunction with protection equipment. It aims at establishing

performance requirements and recommended testing methods for command type teleprotection

equipment. The information conveyed by the teleprotection equipment can be in analogue or

digital form.

The command type teleprotection equipment referred to in this standard can be power line

carrier equipment or voice frequency equipment which is used in connection with various

telecommunication systems, such as power line carrier (PLC), radio links, optical fibre, rented

circuits, leased or privately owned cables. In addition the command type teleprotection can be

digital equipment which is used with a digital telecommunication system or media such as

optical fibres, radio links, leased or privately owned digital links.

The command type teleprotection equipment may be separate or provided as an integral part of

the protection equipment.

In addition to teleprotection equipment performance tests, tests have to be carried out on the

power supply of the teleprotection equipment. All the tests should be regarded as type tests.

NOTE – According to the International Electrotechnical Vocabulary (IEV), a type test is defined as a test of one or

more devices made to a certain design to show that the design meets certain specifications.

1.2 Normative references

The following normative documents contain provisions which, through reference in this text,

constitute provisions of this part of IEC 60834. For dated references, subsequent amendments

to, or revisions of, any of these publications do not apply. However, parties to agreements

based on this part of IEC 60834 are encouraged to investigate the possibility of applying the

most recent editions of the normative documents indicated below. For undated references, the

latest edition of the normative document referred to applies. Members of IEC and ISO maintain

registers of currently valid International Standards.

IEC 60050(151):1978, International Electrotechnical Vocabulary – Chapter 151: Electrical and

magnetic devices

IEC 60050(448):1995, International Electrotechnical Vocabulary – Chapter 448: Power system

protection
---------------------- Page: 11 ----------------------
SIST EN 60834-1:2001
60834-1  IEC:1999 – 11 –

IEC 60060-1:1989, High voltage test techniques – Part 1: General definitions and test

requirements

IEC 60870-2-1:1995, Telecontrol equipment and systems – Part 2: Operating conditions –

Section 1: Power supply and electromagnetic compatibility

IEC 60870-2-2:1996, Telecontrol equipment and systems – Part 2: Operating conditions –

Section 2: Environmental conditions (climatic, mechanical and other non-electrical influences)

IEC 61000-4-1:1992, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement

techniques – Section 1: Overview of immunity tests. Basic EMC publication

ITU-T G.823:1993, The control of jitter and wander within digital networks which are based on

the 2048 kbit/s hierarchy

CISPR 22:1997, Information technology equipment – Radio disturbance characteristics – Limits

and methods of measurement
1.3 Service conditions

With reference to IEC 60870-2-1 and IEC 60870-2-2, the following specifications shall apply.

Special requirements or detailed specifications for other environmental conditions (climatic,

mechanical or other non-electrical influences), not covered in the following but considered

relevant for the proper operation and life of the equipment, shall be agreed between user and

manufacturer, preferably referring to specific classes mentioned in the IEC references above.

Class C2 is the preferred specification for severe environments (temperature range: –25 °C to

+55 °C) except that high relative humidity shall be specified as 95 %.
1.3.1 Ambient conditions

The stated performance requirements shall be satisfied for the conditions corresponding to

location class B3 (enclosed locations – air temperature controlled), the main characteristic

being the following:
• temperature range +5 °C to +40 °C
1.3.2 Supply voltage with battery operation

The nominal d.c. voltage is typically 250 V, 220 V, 125 V, 110 V, 60 V, 48 V or 24 V.

The stated performance requirements shall be satisfied for the following voltage tolerance

class:
• voltage tolerance DC3 –20 % to +15 %
---------------------- Page: 12 ----------------------
SIST EN 60834-1:2001
60834-1  IEC:1999 – 13 –
1.3.3 Supply voltage with a.c. mains operation

The nominal a.c. voltage shall be chosen from the preferred values of 230 V r.m.s. or 110 V r.m.s

single-phase 50 Hz or 60 Hz.

The stated performance requirements shall be satisfied for the following tolerance classes:

• voltage tolerance AC2 +10 % to –15 %
• frequency tolerance F3 ±5 %
• harmonic content H1 <5 %
1.3.4 Storage conditions

During storage or shipment, the equipment shall not suffer any damage when the ambient

conditions correspond to location class C3 for storage and to class C2 for transportation, the

main characteristic being:
• temperature range –40 °C to +70 °C
1.4 Telecommunication system used
The telecommunication system can be
a) cable links for voice frequency transmission;
b) carrier frequency links for cables and overhead lines;
c) carrier frequency links on aerial cables on power lines;
d) power line carrier (PLC) links;
e) point-to-point radio links (microwave);
f) leased circuits;
g) optical fibres.

The telecommunication systems should be chosen with care since they can be influenced by

noise, change of parameters and other types of interference which may cause unwanted

operation or the non-operation of the teleprotection equipment.

Figure 1 shows teleprotection equipment working in an audio-frequency configuration

(e.g. using part of a 4 kHz band). The signals are conveyed from the transmitter to the receiver

via a telecommunication system.
Figure 2 shows a configuration using a power line carrier link.

Figures 1 and 2 apply to teleprotection systems transmitting and receiving frequency shift

keyed carrier or normally quiescent signals.

Figure 3 shows a configuration in which digital teleprotection is directly connected via an

optical fibre.

Figure 4 is an alternative arrangement where the digital teleprotection is connected to a digital

telecommunication system via multiplexing equipment.
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SIST EN 60834-1:2001
60834-1  IEC:1999 – 15 –

Figures 3 and 4 apply to teleprotection systems transmitting and receiving digital data.

Figures 1 to 4 serve only as examples. Other configurations are possible but are not shown.

1.5 Definitions

For the purposes of this part of IEC 60834, the following definitions apply. Refer also to figure 5

which clarifies the relationship between terms in use.
1.5.1
protection

the provisions for detecting faults or other abnormal conditions in a power system, for enabling

fault clearance, for terminating abnormal conditions, and for initiating signals or indications

NOTE 1 – The term "protection" is a generic term for protection equipments or protection systems.

NOTE 2 – The term "protection" may be used to describe the protection of a complete power system or the

protection of individual plant items in a power system e.g. transformer protection, line protection, generator

protection.

NOTE 3 – Protection does not include items of power system plant provided, for example, to limit overvoltages on

the power system. However, it includes items provided to control the power system voltage or frequency deviations

such as automatic reactor switching, load-shedding, etc.
[IEV 448-11-01]
1.5.2
protection equipment

an equipment incorporating one or more protection relays and, if necessary, logic elements

intended to perform one or more specified protection functions
NOTE – A protection equipment is part of a protection system.

Example: Distance protection equipment, phase comparison protection equipment. (One-phase

comparison equipment is part of one line-end of a phase comparison protection system.)

[IEV 448-11-03]
1.5.3
protection system

an arrangement of one or more protection equipments, and other devices intended to perform

one or more specified protection functions

NOTE 1 – A protection system includes one or more protection equipments, instrument transformer(s), wiring,

tripping circuit(s), auxiliary supply(s) and, where provided, communication system(s). Depending upon the

principle(s) of the protection system, it may include one end or all ends of the protected section and, possibly,

automatic reclosing equipment.
NOTE 2 – The circuit-breaker(s) are excluded.
[IEV 448-11-04]
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SIST EN 60834-1:2001
60834-1  IEC:1999 – 17 –
1.5.4
selectivity of protection

the ability of a protection to identify the faulty section and/or phase(s) of a power system

[IEV 448-11-06]
1.5.5
unit protection

a protection whose operation and section selectivity are dependent on the comparison of

electrical quantities at each end of the protected section

NOTE – In the USA, the term "unit protection" designates the protection provided for an electrical generator.

[IEV 448-11-09]
1.5.6
non-unit protection

a protection whose operation and section selectivity are dependent on the measurement of

electrical quantities at one end of the protected section by the measuring relays and, in some

cases, on the exchange of logic signals between the ends

NOTE – The section selectivity of non-unit protection may depend upon its setting, particularly with regard to time.

[IEV 448-11-10]
1.5.7
distance protection

a non-circuit protection whose operation and selectivity depend on local measurement of

electrical quantities from which the equivalent distance to the fault is evaluated by comparing

with zone settings
[IEV 448-14-01]
1.5.8
underreach

the condition of a protection, generally distance protection, when the shortest zone setting

corresponds to a reach shorter than the protected section
[IEV 448-14-05]
1.5.9
overreach

the condition of a protection, generally distance protection, when the shortest zone setting

corresponds to a reach longer than the protected section
[IEV 448-14-07]
1.5.10
teleprotection equipment

equipment specially designed to be used in conjunction with a protection system. The

teleprotection equipment, which is connected to a telecommunication link between both ends of

the protected circuit, transforms the information given by the protection equipment into a form

suitable for transmission
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SIST EN 60834-1:2001
60834-1  IEC:1999 – 19 –
1.5.10.1
teleprotection system

system composed of teleprotection equipment and an associated telecommunication system

between the ends of a protected circuit
1.5.10.2
teleprotection channel

frequency band or bit rate provided by the telecommunication system in order to permit the

transmission of protection signals

NOTE – The teleprotection channel may be either analogue or digital. In an analogue teleprotection channel the

instantaneous signal varies continuously, even though the information is of a digital nature. In a digital

teleprotection channel only certain discrete levels (usually two or three) are permitted. In a digital teleprotection

system, it is usual to convey bit timing information synchronously with the data. This timing information can be

either integrated with the data or transmitted as a separate clock signal depending on the interface type. Timing

information should be regarded as part of the teleprotection channel.
1.5.10.3
telecommunication system – telecommunication link

system composed of telecommunication equipment and the associated physical link required to

transmit information signals over a distance
1.5.11
pilot wire protection
protection associated with telecommunication using metallic wires
[IEV 448-15-04]
1.5.12
power-line-carrier protection
protection associated with telecommunication using power-line carrier
[IEV 448-15-05]
1.5.13
microwave link protection
protection associated with telecommunication using a microwave link
[IEV 448-15-06]
1.5.14
communication-aided distance protection
distance protection which utilises communication to improve its performance
1.5.15
permissive protection

a protection, generally distance protection, in which the receipt of a signal permits the local

protection to initiate tripping
[IEV 448-14-09]
1.5.16
permissive underreach protection (PUP)

protection, generally distance protection, using telecommunication, with underreach protection

at each section end and in which a signal is transmitted when a fault is detected by the

underreach protection. Receipt of the signal at the other end initiates tripping if other local

permissive protection at the other end has detected the fault
[IEV 448-15-11]
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SIST EN 60834-1:2001
60834-1  IEC:1999 – 21 –
1.5.17
permissive overreach protection (POP)

protection, generally distance protection, using telecommunication, with overreach protection at

each section end and in which a signal is transmitted when a fault is detected by the overreach

protection. Receipt of the signal at the other end permits the initiation of tripping by the local

overreach protection
[IEV 448-15-16]
1.5.18
accelerated underreach protection (AUP)

protection, generally distance protection, using telecommunication, with underreach protection

at each section end and in which a signal is transmitted when a fault is detected by the

underreach protection. Receipt of the signal at the other end permits a sequential

measurement by an overreach zone to initiate tripping
[IEV 448-15-13]
1.5.19
blocking protection

a protection, generally distance protection, in which the receipt of a signal blocks the local

protection from initiating tripping
[IEV 448-14-10]
1.5.20
blocking overreach protection (BOP)

protection, generally distance protection, using telecommunication, with overreach protection at

each section end and in which a signal is transmitted when a reverse external fault is detected.

Receipt of the signal at the other end blocks the overreach protection at that end from initiating

tripping
[IEV 448-15-14]
1.5.21
longitudinal differential protection

protection the operation and selectivity of which depend on the comparison of magnitude or the

phase and magnitude of the currents at the ends of the protected section
[IEV 448-14-16]
1.5.22
phase comparison protection

protection whose operation and selectivity depend on the comparison of the phase of the

currents at each end of the protected section
[IEV 448-14-18]
1.5.23
intertripping

the tripping of circuit-breaker(s) by signals initiated from protection at a remote location

independent of the state of the local protection
[IEV 448-15-08]
---------------------- Page: 17 ----------------------
SIST EN 60834-1:2001
60834-1  IEC:1999 – 23 –
2 Characteristics of command type teleprotection systems

The following subclauses deal with the terms used in the description and/or specification of

teleprotection systems (see also 3.3.1).
2.1 Types of teleprotection command schemes
a) Permissive tripping schemes (see 1.5)

This term refers to schemes where the received command initiates tripping in conjunction

with a local protection equipment. Command channels of this type can operate in an audio

frequency band, a PLC frequency band or at a digital bit rate. The channel is often

designed with the premise that dependability of operation should be high even under

conditions when, due to a power system disturbance, the telecommunication medium may

be adversely affected.
b) Intertripping schemes (direct or transfer tripping) (see 1.5)

This term refers to schemes where the received command initiates tripping without

qualification by local protection. Intertrip channels utilise similar principles to permissive trip

channels; however, security against unwanted operation and dependability of correct

operation are prime requirements. Speed of operation is usually sacrificed to meet security

and dependability requirements, particularly in analogue systems.
c) Blocking protection schemes (see 1.5)

This term refers to schemes where the received command blocks the operation of local

protection. These channels utilise similar principles to permissive trip channels; however,

dependability of operation and speed are prime requirements.
2.2 Overall operating time of teleprotection systems
(telecommunication circuit included)

The overall operating time T is the time elapsed between the instant of change in state at the

command input and the instant of the corresponding change in state at the command output,

including propagation time and additional delay due to noise.

The overall operating time of a teleprotection system influences the fault clearance time (see

figure 6).
NOTE – Fault clearance time T as shown in figure 6 is typical only.
2.3 Transmission times (telecommunication circuit excluded)

The transmission time of a teleprotection system is the time elapsed between the instant of

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