Instrument transformers - Part 7: Electronic voltage transformers

Applies to newly manufactured electronic voltage transformers with analogue output, for use with electrical measuring instruments and electrical protective devices at frequencies from 15 Hz to 100 Hz. The standard covers optical arrangements with electronic components. Three-phase voltage transformers are not included, but some of the requirements apply.

Meßwandler - Teil 7: Elektronische Spannungswandler

Transformateurs de mesure - Partie 7: Transformateurs de tension électroniques

S'applique aux transformateurs de tension électroniques nouvellement construits, ayant une sortie analogique, et destinés à être utilisés avec des appareils de mesure électriques et des dispositifs éelctriques de protection de fréquence comprise entre 15 Hz et 100 Hz. S'applique aux transformateurs de tension utilisant des configurations optiques avec des composants électroniques. Les transformateurs de tension électroniques triphasés ne sont pas couverts mais certains articles sont applicables.

Instrument transformers - Part 7: Electronic voltage transformers

General Information

Status
Withdrawn
Publication Date
23-Jan-2000
Drafting Committee
Parallel Committee
Current Stage
6060 - Document made available
Due Date
24-Jan-2000
Completion Date
24-Jan-2000

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SLOVENSKI STANDARD
SIST EN 60044-7:2000
01-junij-2000
Instrument transformers - Part 7: Electronic voltage transformers
Instrument transformers -- Part 7: Electronic voltage transformers
Meßwandler -- Teil 7: Elektronische Spannungswandler
Transformateurs de mesure -- Partie 7: Transformateurs de tension électroniques
Ta slovenski standard je istoveten z: EN 60044-7:2000
ICS:
17.220.20 0HUMHQMHHOHNWULþQLKLQ Measurement of electrical
PDJQHWQLKYHOLþLQ and magnetic quantities
SIST EN 60044-7:2000 en

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

---------------------- Page: 1 ----------------------
SIST EN 60044-7:2000
---------------------- Page: 2 ----------------------
SIST EN 60044-7:2000
EUROPEAN STANDARD EN 60044-7
NORME EUROPÉENNE
EUROPÄISCHE NORM January 2000
ICS 17.220.20
English version
Instrument transformers
Part 7: Electronic voltage transformers
(IEC 60044-7:1999)
Transformateurs de mesure Meßwandler
Partie 7: Transformateurs de Teil 7: Elektronische Spannungswandler
tension électroniques (IEC 60044-7:1999)
(CEI 60044-7:1999)

This European Standard was approved by CENELEC on 1999-12-01. CENELEC members are bound to

comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this

European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on

application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CENELEC member into its own language and

notified to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic,

Central Secretariat: rue de Stassart 35, B - 1050 Brussels
CENELEC

© 2000 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

European Committee for Electrotechnical Standardization
Ref. No. EN 60044-7:2000 E
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway,

Portugal, Spain, Sweden, Switzerland and United Kingdom.
---------------------- Page: 3 ----------------------
SIST EN 60044-7:2000
Page 2
EN 60044-7:2000
Foreword

The text of document 38/242/FDIS, future edition 1 of IEC 60044-7, prepared by IEC TC 38,

Instrument transformers, was submitted to the IEC-CENELEC parallel vote and was approved by

CENELEC as EN 60044-7 on 1999-12-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2000-10-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2002-12-01
Annexes designated "normative" are part of the body of the standard.
Annexes designated "informative" are given for information only.

In this standard, annexes A and ZA are normative and annexes B and C are informative.

Annex ZA has been added by CENELEC.
__________
Endorsement notice

The text of the International Standard IEC 60044-7:1999 was approved by CENELEC as a European

Standard without any modification.
__________
---------------------- Page: 4 ----------------------
SIST EN 60044-7:2000
Page 3
EN 60044-7:2000
Annex ZA (normative)
Normative references to international publications
with their corresponding European publications

This European Standard incorporates by dated or 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 European Standard only when incorporated in it by

amendment or revision. For undated references the latest edition of the publication referred to

applies (including amendments).

NOTE: When an international publication has been modified by common modifications, indicated by (mod), the

relevant EN/HD applies.
Publication Year Title EN/HD Year
IEC 60038 (mod) 1983 HD 472 S1 1989
IEC standard voltages
IEC 60044-2 1997 Instrument transformers EN 60044-2 1999
(mod) Part 2: Inductive voltage transformers
IEC 60050-161 1990 International Electrotechnical - -
Vocabulary (IEV)
Chapter 161: Electromagnetic compatibility
IEC 60050-321 1986 Chapter 321: Instrument transformers - -
IEC 60050-601 1985 Chapter 601: Generation, transmission and - -
distribution of electricity - General
IEC 60050-604 1987 Chapter 604: Generation, transmission and - -
distribution of electricity - Operation
IEC 60060-1 1989 High-voltage test techniques HD 588.1 S1 1991
+ corr. March 1990 Part 1: General definitions and test
requirements
IEC 60071-1 1993 Insulation co-ordination EN 60071-1 1995
Part 1: Definitions, principles and rules
IEC 60186 (mod) 1987 Voltage transformers 1992
HD 554 S1
IEC 60255-5 1977 Electrical relays - -
Part 5: Insulation tests for electrical relays
IEC 60255-6 1988 Part 6: Measuring relays and protection EN 60255-6 1994
(mod) equipment + corr. February 1995
IEC 60255-11 1979 Part 11: Interruptions to and alternating - -
component (ripple) in d.c. auxiliary energizing
quantity of measuring relays
Page 4
EN 60044-7:2000

) The title of HD 472 S1 is: Nominal voltages for low-voltage public electricity supply systems.

) HD 554 S1 includes A1:1988 to IEC 60186, mod.
---------------------- Page: 5 ----------------------
SIST EN 60044-7:2000
Publication Year Title EN/HD Year
IEC 60255-22-1 1988 Part 22: Electrical disturbance tests for - -
measuring relays and protection equipment
Section 1: 1 MHz burst disturbance tests
IEC 60270 1981 Partial discharge measurements - -
IEC 60617-1 1985 Graphical symbols for diagrams - -
Part 1: General information, general index,
Cross-reference tables
IEC 60694 1996 Common specifications for high-voltage EN 60694 1996
switchgear and controlgear standards + corr. May 1999
IEC 60721 series Classification of environmental conditions EN 60721 series
HD 478 series
IEC 60815 1986 Guide for the selection of insulators in respect - -
of polluted conditions
IEC 61000-4-1 1992 Electromagnetic compatibility (EMC) EN 61000-4-1 1994
Part 4: Testing and measurement techniques
Section 1: Overview of immunity tests
IEC 61000-4-2 1995 Part 4-2: Testing and measurement EN 61000-4-2 1995
techniques - Electrostatic discharge immunity
test
IEC 61000-4-3 1995 Part 4-3: Testing and measurement EN 61000-4-3 1996
(mod) techniques - Radiated, radio-frequency,
electromagnetic field immunity test
IEC 61000-4-4 1995 Part 4-4: Testing and measurement EN 61000-4-4 1995
techniques - Electrical fast transient/burst
immunity test
IEC 61000-4-5 1995 Part 4-5: Testing and measurement EN 61000-4-5 1995
techniques - Surge immunity test
IEC 61000-4-8 1993 Part 4-8: Testing and measurement EN 61000-4-8 1993
techniques - Power frequency magnetic field
immunity test
IEC 61000-4-9 1993 Part 4-9: Testing and measurement EN 61000-4-9 1993
techniques - Pulse magnetic field immunity
test
IEC 61000-4-10 1993 Part 4-10: Testing and measurement EN 61000-4-10 1993
techniques - Damped oscillatory magnetic
field immunity test
---------------------- Page: 6 ----------------------
SIST EN 60044-7:2000
Page 5
EN 60044-7:2000
Publication Year Title EN/HD Year
IEC 61000-4-11 1994 Part 4-11: Testing and measurement EN 61000-4-11 1994
techniques - Voltage dips, short interruptions
and voltage variations immunity tests
IEC 61000-4-12 1995 Part 4-12: Testing and measurement EN 61000-4-12 1995
techniques - Oscillatory waves immunity test -
Basic EMC publication
CISPR 11 (mod) 1997 Industrial, scientific and medical (ISM) EN 55011 1998
radio-frequency equipment - Radio
disturbance characteristics - Limits and
methods of measurement
Electromagnetic compatibility - Generic EN 50081-2 1993
emission standard
Part 2: Industrial environment
---------------------- Page: 7 ----------------------
SIST EN 60044-7:2000
---------------------- Page: 8 ----------------------
SIST EN 60044-7:2000
INTERNATIONAL IEC
STANDARD 60044-7
First edition
1999-12
Instrument transformers –
Part 7:
Electronic voltage transformers
 IEC 1999 Copyright - all rights reserved

No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical,

including photocopying and microfilm, without permission in writing from the publisher.

International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland

Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch

PRICE CODE
Commission Electrotechnique Internationale
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue
---------------------- Page: 9 ----------------------
SIST EN 60044-7:2000
60044-7 © IEC:1999 – 3 –
CONTENTS
Page

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

Clause

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

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

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

1.3 General block diagram of electronic voltage transformers ..................................... 13

2 Definitions...................................................................................................................... 15

2.1 General definitions................................................................................................ 15

2.2 Additional definitions for single-phase electronic protective voltage

transformers ......................................................................................................... 27

2.3 Index of symbols................................................................................................... 27

3 General requirements .................................................................................................... 31

3.1 General................................................................................................................. 29

3.2 Information to be given for enquiries, tenders and orders...................................... 31

4 Normal and special service conditions ........................................................................... 31

4.1 Normal service conditions ..................................................................................... 31

4.2 Special service conditions..................................................................................... 35

4.3 Earthing system .................................................................................................... 37

5 Ratings .......................................................................................................................... 37

5.1 Standard values of rated voltages......................................................................... 37

5.2 Standard values of rated output ............................................................................ 39

5.3 Standard values of rated voltage factor................................................................. 39

5.4 Standard values of rated auxiliary power supply voltage ....................................... 41

5.5 Standard reference values of other influencing parameters................................... 41

6 Design requirements ...................................................................................................... 43

6.1 Insulation requirements for primary voltage sensor ............................................... 43

6.2 Insulation requirements for low-voltage components ............................................. 51

6.3 Short-circuit withstand capability........................................................................... 53

6.4 Limits of temperature rise ..................................................................................... 53

6.5 Radio interference voltage requirements............................................................... 53

6.6 Transmitted overvoltage requirements .................................................................. 55

6.7 Electromagnetic compatibility requirements .......................................................... 55

6.8 Reliability.............................................................................................................. 59

6.9 Abnormal conditions withstand capability .............................................................. 61

6.10 Abnormal conditions signalling.............................................................................. 61

6.11 Mechanical requirements ...................................................................................... 61

6.12 Earthing terminals................................................................................................. 63

7 Classification of tests ..................................................................................................... 63

7.1 Type tests............................................................................................................. 63

7.2 Routine tests ........................................................................................................ 65

7.3 Special tests ......................................................................................................... 65

---------------------- Page: 10 ----------------------
SIST EN 60044-7:2000
60044-7 © IEC:1999 – 5 –
Clause Page

8 Type tests...................................................................................................................... 65

8.1 Impulse test on primary voltage terminals ............................................................. 65

8.2 Wet test for outdoor type electronic voltage transformers...................................... 69

8.3 Tests for accuracy ................................................................................................ 69

8.4 Test for abnormal conditions withstand capability ................................................. 71

8.5 Radio interference voltage test ............................................................................. 73

8.6 Transmitted overvoltage test................................................................................. 73

8.7 Electromagnetic compatibility tests ....................................................................... 73

8.8 Impulse voltage withstand test for low-voltage components .................................. 79

8.9 Transient performance tests ................................................................................. 81

9 Routine tests..................................................................................................................81

9.1 Verification of terminal markings ........................................................................... 81

9.2 Power-frequency withstand tests on primary voltage terminals

and partial discharge measurement ...................................................................... 81

9.3 Power-frequency voltage withstand test for low-voltage components .................... 85

9.4 Tests for accuracy ................................................................................................ 87

10 Special tests .................................................................................................................. 87

10.1 Chopped lightning-impulse test on primary voltage terminals ................................ 87

10.2 Measurement of capacitance and dielectric dissipation factor ............................... 89

10.3 Mechanical strength tests ..................................................................................... 89

11 Markings ........................................................................................................................ 91

11.1 Rating plate markings ........................................................................................... 91

11.2 Terminal markings ................................................................................................ 95

12 Accuracy requirements for single-phase electronic measuring voltage transformers....... 95

12.1 General requirements ........................................................................................... 95

12.2 Maintenance requirement...................................................................................... 97

12.3 Accuracy class designation for electronic measuring voltage transformers............ 97

12.4 Standard accuracy classes for electronic measuring voltage transformers ............ 97

12.5 Limits of voltage error and phase displacement for electronic measuring

voltage transformers ............................................................................................. 99

13 Additional requirements for single-phase electronic protective voltage transformers ...... 99

13.1 General requirements ........................................................................................... 99

13.2 Maintenance requirements.................................................................................. 101

13.3 Accuracy class designation for electronic protective voltage transformers........... 101

13.4 Standard accuracy classes for electronic protective voltage transformers ........... 101

13.5 Limits of voltage error and phase displacement for electronic protective

voltage transformers ........................................................................................... 101

13.6 Transient performance requirements................................................................... 103

Annex A (normative) Burdens for the transient response test ............................................. 105

Annex B (informative) Technical information for electronic voltage transformers................. 109

Annex C (informative) Bibliography .................................................................................... 137

---------------------- Page: 11 ----------------------
SIST EN 60044-7:2000
60044-7 © IEC:1999 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INSTRUMENT TRANSFORMERS –
Part 7: Electronic voltage transformers
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 60044-7 has been prepared by IEC technical committee 38:

Instrument transformers
The text of this standard is based on the following documents:
FDIS Report on voting
38/242/FDIS 38/243/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.

The committee has decided that this publication remains valid until 2002. At this date, in

accordance with the committee's decision, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition; or
• amended.
---------------------- Page: 12 ----------------------
SIST EN 60044-7:2000
60044-7 © IEC:1999 – 9 –
INSTRUMENT TRANSFORMERS –
Part 7: Electronic voltage transformers
1 General
1.1 Scope

This part of International Standard IEC 60044 applies to newly manufactured electronic

voltage transformers with analogue output, for use with electrical measuring instruments and

electrical protective devices at frequencies from 15 Hz to 100 Hz.

NOTE 1 Optical arrangements usually include electronic components and are therefore considered to be within

the application of this standard.
NOTE 2 Detailed information is given in annex B.

NOTE 3 Requirements specific to three-phase voltage transformers are not included in this standard but, so far as

they are relevant, the requirements in clauses 3 to 11 apply to these transformers and a few references to them are

included in those clauses (e.g. see 2.1.5, 5.1.1, 5.2, 11.2.1 and 11.2.2).
1.2 Normative references

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

constitute provisions of this part of IEC 60044. For dated references, subsequent amend-

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

agreements based on this part of IEC 60044 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 60038:1983, IEC standard voltages

IEC 60044-2:1997, Instrument transformers – Part 2: Inductive voltage transformers

IEC 60050(161):1990, International Electrotechnical Vocabulary (IEV) – Chapter 161:

Electromagnetic compatibility

IEC 60050(321):1986, International Electrotechnical Vocabulary (IEV) – Chapter 321:

Instrument transformers

IEC 60050(601):1985, International Electrotechnical Vocabulary (IEV) – Chapter 601:

Generation, transmission and distribution of electricity – General

IEC 60050(604):1987, International Electrotechnical Vocabulary (IEV) – Chapter 604:

Generation, transmission and distribution of electricity – Operation
IEC 60060 (all parts), High-voltage techniques

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

requirements

IEC 60071-1:1993, Insulation co-ordination – Part 1: Definitions, principles and rules

---------------------- Page: 13 ----------------------
SIST EN 60044-7:2000
60044-7 © IEC:1999 – 11 –
IEC 60186:1987, Voltage transformers

IEC 60255-5:1977, Electrical relays – Part 5: Insulation tests for electrical relays

IEC 60255-6:1988, Electrical relays – Part 6: Measuring relays and protection equipment

IEC 60255-11:1979, Electrical relays – Part 11: Interruptions to and alternating component

(ripple) in d.c. auxiliary energizing quantity of measuring relays

IEC 60255-22-1:1988, Electrical relays – Part 22: Electrical disturbance tests for measuring

relays and protection equipment – Section 1: 1 MHz burst disturbance tests
IEC 60270:1981, Partial discharges measurements

IEC 60617-1:1985, Graphical symbols for diagrams – Part 1: General information, general

index. Cross-reference tables

IEC 60694:1996, Common specifications for high-voltage switchgear and controlgear

standards
IEC 60721 (all parts), Classification of environmental conditions

IEC 60815:1986, Guide for the selection of insulators in respect of polluted conditions

IEC 61000 (all parts), Electromagnetic compatibility (EMC)

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

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

IEC 61000-4-2:1995, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement

techniques – Section 2: Electrostatic discharge immunity test. Basic EMC publication

IEC 61000-4-3:1995, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement

techniques – Section 3: Radiated, radio-frequency, electromagnetic immunity test

IEC 61000-4-4:1995, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement

techniques – Section 4: Electrical fast transient/burst immunity test. Basic EMC publication

IEC 61000-4-5:1995, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement

techniques – Section 5: Surge immunity test

IEC 61000-4-8:1993, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement

techniques – Section 8: Power frequency magnetic field immunity test. Basic EMC publication

IEC 61000-4-9:1993, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement

techniques – Section 9: Pulse magnetic field immunity test. Basic EMC publication

IEC 61000-4-10:1993, Electromagnetic compatibility (EMC) – Part 4: Testing and

measurement techniques – Section 10: Damped oscillatory magnetic field immunity test.

Basic EMC publication
---------------------- Page: 14 ----------------------
SIST EN 60044-7:2000
60044-7 © IEC:1999 – 13 –
IEC 61000-4-11:1994, Electromagnetic compatibility (EMC) – Part 4: Testing and

measurement techniques – Section 11: Voltage dips, short interruption and voltage variation

immunity test
IEC 61000-4-12:1995, Electromagnetic compatibility (EMC) – Part 4: Testing and
measurement techniques – Section 12: Oscillatory waves immunity tests. Basic EMC
publication

CISPR 11 (EN 55011), Industrial, scientific and medical (ISM) radio-frequency equipment –

Electromagnetic disturbance characteristics – Limits and methods of measurement

EN 50081-2:1993, Electromagnetic compatibility – Generic immunity standard – Part 2:

Industrial environment
1.3 General block diagram of electronic voltage transformers

The applied technology decides which parts are necessary for realisation of an electronic

voltage transformer, i.e. it is not absolutely essential that all parts described be in the

transformer (see figures 1 and 2).
Primary
A a
voltage Primary Transmitting Secondary
sensor converter system converter
N n
Primary voltage Secondary voltage
terminals terminals
Primary Secondary
power power
supply supply
IEC 1192/99

Figure 1 – General block diagram of earthed single-phase electronic voltage transformers

Primary
A a
voltage
sensor
N n
Primary
B b
Primary Secondary
voltage Transmitting
converter converter
sensor system
N n
Primary
C c
voltage
sensor
N n
Primary voltage Secondary voltage
terminals terminals
Primary Secondary
power power
supply supply
IEC 1193/99

Figure 2 – General block diagram of earthed three-phase electronic voltage transformers

---------------------- Page: 15 ----------------------
SIST EN 60044-7:2000
60044-7 © IEC:1999 – 15 –
2 Definitions
For the purpose of this part of IEC 60044, the following definitions apply.
2.1 General definitions
2.1.1
electronic instrument transformer

an arrangement consisting of one or more current or voltage sensors which may be connected

to a transmitting system and a secondary converter, all intended to transmit a measuring

quantity in a proportional quantity to supply measuring instruments, meters and protective or

control devices
2.1.2
electronic voltage transformer

an electronic instrument transformer in which the secondary voltage in normal conditions of

use is substantially proportional to the primary voltage and differs in phase from it by an angle

which is approximately zero for an appropriate direction of the connections
2.1.3
electronic measuring voltage transformer

an electronic voltage transformer intended to transmit an information signal to measuring

instruments and meters
2.1.4
unearthed electronic voltage transformer

an electronic voltage transformer in which all parts of the primary voltage sensor, including

terminals
...

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