IEC 60131-4

SLOVENSKI STANDARD
SIST IEC 60255-12:1995
01-avgust-1995
Electrical relays - Part 12: Directional relays and power relays with two input
energizing quantities
Electrical relays - Part 12: Directional relays and power relays with two input energizing
quantities
Relais électriques - Douzième partie: Relais directionnels et relais de puissance à deux
grandeurs d'alimentation d'entrée
Ta slovenski standard je istoveten z: IEC 60255-12
ICS:
29.120.70 Releji Relays
SIST IEC 60255-12:1995 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST IEC 60255-12:1995

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SIST IEC 60255-12:1995
NORME CEI
INTERNATIONALE IEC
255-12
INTERNATIONAL
Première
édition
STANDARD
First edition
1980
Relais électriques
Douzième partie:
Relais directionnels et relais de puissance
à deux grandeurs d'alimentation d'entrée
Electrical relays
Part 12:
Directional relays and power relays with
two input energizing quantities
© CEI 1980 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 pro- any form or by any means, electronic or mechanical,
cédé, électronique ou mécanique, y compris la photocopie et including photocopying and microfilm, without permission
les microfilms, sans l'accord écrit de l'éditeur. in writing from the publisher.
Bureau Central de la Commission Electrotechnique Internationale 3, rue de Varembé Genève, Suisse
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CODE PRIX
International Electrotechnical Commission
PRICE CODE 'vl
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Mes
IEC
Pour prix, voir catalogue en vigueur
•
For price, see current catalogue

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SIST IEC 60255-12:1995
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CONTENTS
Page
FOREWORD 5
PREFACE 5
SECTION ONE — SCOPE AND DEFINITIONS
Clause
1. Scope 7
2. Definitions 7
SECTION Two - REQUIREMENTS
3. Standard values 9
4. Operation and accuracy 15
5. Methods of presenting relay characteristics and performance 17
6. Thermal requirements 17
17
7. Mechanical requirements
8. Values of the limits of the operative range of the auxiliary energizing quantities 17
9. Contact performance 17
10. Rated burden 17
11. Insulation 19
12. Marking and data 19
13. High frequency disturbance test 19
SECTION THREE — TEST METHODS
14. Tests related to accuracy and operating characteristics 19
15. Tests for thermal requirements 21
16. Tests for mechanical requirements 21
FIGURES 22-26

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SIST IEC 60255-12:1995
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INTERNATIONAL ELECTROTECHNICAL COMMISSION
ELECTRICAL RELAYS
Part 12: Directional relays and power relays with two input
energizing quantities
FOREWORD
1) The formal decisions or agreements of the IEC on technical matters, prepared by Technical Committees on which all the
Committees having a special interest therein are represented, express, as nearly as possible, an inte rnational consensus of
opinion on the subjects dealt with.
2) They have the form of recommendations for international use and they are accepted by the National Committees in that
sense.
3) In order to promote international unification, the IEC expresses the wish that all National Committees should adopt the
text of the IEC recommendation for their national rules in so far as national conditions will permit. Any divergence
between the IEC recommendation and the corresponding national rules should, as far as possible, be clearly indicated in
the latter.
PREFACE
This standard has been prepared by Sub-Committee 41B: Measuring Relays, of IEC Technical
Committee No. 41: Electrical Relays.
Drafts were discussed at the meetings held in Nice in 1976 and in Milan in 1977. A draft,
Document 41B(Central Office)10, was submitted to the National Committees for approval under the
Six Months' Rule in May 1978.
The National Committees of the following countries voted explicitly in favour of publication:
Australia Germany Spain
Austria Italy Sweden
Belgium Japan Switzerland
Norway Turkey
Canada
Egypt Poland United Kingdom
France South Africa (Republic of) United States of America
This standard, applicable to a particular group of measuring relays with more than one input
energizing quantity, is hierarchically a third-level document: Standards applicable wholly or partly to
a particular group of relays.
Other IEC publications quoted in this standard:
Publications Nos. 50(131): International Electrotechnical Vocabulary, Chapter 131: Electric and Magnetic Circuits.
ance of Electrical Relays.
255-0-20: Electrical Relays - Contact Perform
255-4: Single Input Energizing Quantity Measuring Relays with Dependent Specified Time.
255-5: Electrical Relays, Part 5: Insulation Tests for Electrical Relays.
255-6: Part 6: Measuring Relays with More than One Input Energizing Quantity.

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SIST IEC 60255-12:1995
—7—
ELECTRICAL RELAYS
Part 12: Directional relays and power relays with two input
energizing quantities
SECTION ONE - SCOPE AND DEFINITIONS
1. Scope
This standard specifies the performance requirements of directional relays and power relays
with two input energizing quantities, which constitute a particular sub-family of measuring
relays with more than one input energizing quantity as defined in I EC Publication 255-6,
Electrical Relays, Part 6: Measuring Relays with More than One Input Energizing Quantity,
and the parameters whose values are to be declared by the manufacturer of such relays. It also
specifies methods of presenting the characteristics and performance of these relays.
This standard excludes impedance relays and deals specifically with:
-
relays measuring phase angle (direction);
- relays measuring power.
The requirements in this standard relating to phase angle (direction) can be combined with
requirements relating to other characteristics (e. g. current) specified in other pa rts of the
I E C 255 series publications, so as to cover combinations such as "directional current relays".
For particular c ases, supplementary requirements may be agreed between the manufacturer
and the user or may be specified in national standards.
All tests in this standard are type tests.
This standard applies only to the relays in new condition.
2. Definitions
General terms are defined in I E C Publication 255-6 and in the International Electrotechnical
Vocabulary (I.E.V.).
For the purpose of this standard, the following additional definitions shall apply:
2.1 Directional (phase angle measuring) relay
A relay with two input energizing quantities and which, by its design, is intended to respond
only to the relative phase position of a current or voltage with respect to another current or
voltage reference.
2.2
Power relay
A relay with two input energizing quantities, current and voltage and which, by its design, is
intended to respond only to power.

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SIST IEC 60255-12:1995
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2.3
Characteristic angle of power and directional relays*
The angle between the phasors representing the two energizing quantities, which is used for
the declaration of the performance of the relay.
Note. —
Particularly for electromechanical relays, it is usually the angle at which the maximum sensitivity occurs.
2.4
Connection angle of power and directional relays*
The angle between the voltages which are identified with the phasors representing the two
energizing quantities.
2.5 Directional sensitivity
The minimum value of one input energizing quantity at which the relay operates, the other
input energizing quantity being at its reference value and the angle between the input energizing
quantities being the characteristic angle.
SECTION TWO — REQUIREMENTS
3. Standard values
3.1
Input and auxiliary energizing quantities and frequency
The standard values of input and auxiliary energizing quantities and of frequency are as
specified in IEC Publication 255-6.
3.1.1
Effective range of input energizing quantities
There are no standard effective ranges of input energizing quantities. These shall be declared
by the manufacturer.
3.2 Characteristic angle and connection angle
3.2.1
Value of characteristic angle and connection angle
There are no standard values of the characteristic and connection angles. The characteristic
angle, and the connection angle if any, shall be declared by the manufacturer. Other connection
angles for various applications may also be declared by the manufacturer (see note with an
asterisk, relating to Sub-clauses 2.3 and 2.4).
3.2.2
Setting range of characteristic angle
There are no standard setting ranges. The setting ranges of the characteristic angle, if any,
shall be declared by the manufacturer.
3.3 Specified times
There are no standard rated values for specified times. The manufacturer shall declare
whether the relay has independent or dependent specified times.
Note. —
Dependent time characteristics are mainly applicable to power relays. For a directional relay, for which the
characteristic quantity is angle, dependent times are applicable only in special cases.
* A given relay may have more than one characteristic angre. On the other hand, a given relay may be connected in alternative
modes, e. g. by links, with a variety of connection angles. The combination of a given characteristic angle with a given
connection angle results in an overall performance effective for a given application.

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SIST IEC 60255-12:1995
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3.3.1 Independent specified time relays
Independent specified times shall be declared by the manufacturer.
3.3.2
Dependent time relays with increasing function
The shape of the characteristic curve shall be declared by the manufacturer (see Clause 5).
3.3.3 Dependent time relays with decreasing function
The shape of the characteristic curve shall be declared by the manufacturer (see Clause 5).
The most common characteristic curves for relays with decreasing function are given in Sub-
clause 3.5.2 of I EC Publication 255-4: Single Input Energizing Quantity Measuring Relays
with Dependent Specified Time.
Note. — Dependent time characteristics are mainly applicable to power relays. For a directional relay, for which the
characteristic quantity is angle, dependent times are applicable only in special cases.
3.4 Resetting times
There are no standard values of resetting times. The values shall be declared by the
manufacturer.
TABLE I
Standard reference conditions and test tolerances of
influencing quantities and factors
Influencing quantity of factor Reference condition
Test tolerance
Reference input energizing
quantity
To be declared by the manufacturer or in national standards
unless specified in clauses below or in lower level
documents
Non-reference input energizing
quantity
y
C_ 4:
To be declared by the
-0 c
a o Phase angle between input energizing Declared characteristic
al
manufacturer or in national
quantities (see Note 1)
Cr angle or range of angles
standards
NN
Û W
D.C. component
as c
Transient Zero (see Note 2) %
5 of peak a. c. value
in i a. c.
Û N
To be declared by the manufacturer or in national
Setting value(s), where setting adjustments
standards unless specified in clauses below or in lower
are possible
level documents
ao
I. n .?;
cz '^ u D.C
. component
Transient Zero (see Note 2)
5% of peak a. c. value
° = in a. c.
. ;,
ç
e
Notes 1.— A reference phase angle is necessary for directional relays when measuring time and sensitivity.
2.— In the special case of relays in which polyphase measurements are made on a single relay, the manufacturer
or national standards shall define which of the input currents shall be under reference conditions.

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SIST IEC 60255-12:1995
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TABLE II
Standard values of the limits of the nominal ranges of
influencing quantities and factors
Influencing quantity or factor Nominal range
Reference input energizing quantity
Non-reference input energizing quantity
cts
c Phase angle g between input p energizing g g quantities
es
°' As declared by manufacturer or in national
standards
—
Frequency
I
â â
to
U
Waveform
Steady state
D.C. component in a. c.
transient
Voltage or current
As declared by the manufacturer or in national
standards unless specified in clauses
Frequency
cN below
Waveform
4{
4
..'.ccrs
A. C. component in d. c. (ripple) 0 to 12 010 of the rated d. c. value*'
0
As declared by the manufacturer or in national
Steady state
standards unless specified in clauses
D.C. component in a.c.
transient
below
* This value of tolerance applies to peak-ripple factor (I.E.V. 131-03-14).
3.5
Standard reference values of influencing quantities and factors and standard values of their
nominal and extreme ranges
3.5.1
Standard reference values of influencing quantities and factors
The standard reference conditions are given in Table I of I E C Publication 255-6. In
addition, the standard conditions specified in Table I of this standard apply to directional relays
and power relays.
3.5.2
Limits of the nominal ranges of the influencing quantities and factors
The standard values are specified in Table II of I EC Publication 255-6. In addition, the
standard values specified in Table II of this standard apply to power and directional relays.
3.6
Characteristic quantities and setting range(s)
There are no standard rated values of either characteristic quantity(ies) or setting range(s).
These values and the limits of setting range(s) shall be specified by the manufacturer.

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SIST IEC 60255-12:1995
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3.7 Resetting and disengaging values
The resetting and disengaging values shall be declared by the manufacturer.
In the case of power relays, these values shall be specified as ratios or percentage.
In the case of directional relays, they shall be specified in degrees at the boundaries.
4. Operation and accuracy
4.1 Operation
4.1.1 Operating characteristics
The manufacturer shall declare the operating characteristics of the relay under reference
conditions, including the reference setting value. If desirable, the manufacturer may declare the
operating characteristics in terms of the combined effect of the characteristic angle and the
connection angle.
4.1.2 Operating and rese
...