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    CSC-326Transformer Protection IED

    Product Guide

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    Version V1.0

    Doc. Code: 0SF.492.054(E)

    Issued Date 201.

    Copyright owner: Beijing Sifang Automation Co., Ltd.

    Note: The company keeps the right to perfect the instruction. If equipments do not agree with the

    instruction at anywhere, please contact our company in time. We will provide you with corresponding

    service.

    is registered trademark of Beijing Sifang Automation Co., Ltd.

    We reserve all rights to this document, even in the event that a patent is issued and a different

    commercial proprietary right is registered. Improper use, in particular reproduction and dissemination

    to third parties, is not permitted.

    This document has been carefully checked. If the user nevertheless detects any errors, he is asked to

    notify us as soon as possible.

    The data contained in this manual is intended solely for the IED description and is not to be deemed

    to be a statement of guaranteed properties. In the interests of our customers, we constantly seek to

    ensure that our products are developed to the latest technological standards as a result; it is possible

    that there may be some differences between the hardware/software product and this information

    product.

    Manufacturer:

    Beijing Sifang Automation Co., Ltd.

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    Overview

    1

    CSC-326 is selective, reliable and high

    speed IED (Intelligent Electronic Device)

    for transformer or reactor protection with

    powerful capabilities to cover following

    applications:

    For large and medium two-winding or

    three-winding transformer, and auto-

    -transformer

    Shunt reactors with/without neutralpoint grounding reactor

    Used in a wide range of voltage levels,

    up to 1000kV

    For single or multi-breaker arrange-

    -ment

    Up to 7 three-phase sets of CTs

    input (special ordering)

    Work as main protection unit only

    or full functions unit for the

    complicated application

    Communication with station automation

    system

    The IED is able to provide all main

    protection functions and backup protection

    functions in one case, including differential

    protection for transformer or reactor,

    restricted earth fault (REF), overexcitation,

    thermal overload, overcurrent, earth faultprotection, etc.

    The integrated flexible logic make the IED

    suitable to be applied to (auto)transformers

    with all the possible vector groups,

    with/without earthing connection inside the

    protected zone.

    The wide application flexibility makes the

    IED an excellent choice for both new

    installations and retrofitting of the existing

    stations.

    .

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    Feature

    2

    Protection and monitoring IED with

    extensive functional library, user

    configuration possibility and expand-

    -able hardware design to meet withusers special requirements

    Inter-lock between two CPU modules,

    avoiding mal-operation due to internal

    severe fault of one module

    Transformer differential protection

    (87T)

    Treble slope percent differential

    protection

    Automatic CT ratio matching

    Automatic vector group and zero

    sequence current compensation

    Settable 2nd harmonic restraint

    function for transformer inrush

    Fuzzy waveform recognition

    restraint function for transformer

    inrush

    3rd or 5th harmonic restraint for

    overexcitation

    CT saturation detection

    CT secondary circuit supervison

    Differential current alarm

    Reactor differential protection (87R)

    Treble slope percent differential

    protection

    Automatic CT ratio matching

    CT saturation detection

    CT secondarycircuit supervison

    Differential current supervision

    Restricted earth fault protection fortransformer (87NT)

    Two slope percent REF protection

    Automatic CT ratio matching

    CT saturation recognition

    REF differential current super-

    -vision

    Restricted earth fault protection for

    reactor(87NR)

    Two slope percent REF protection

    Automatic CT ratio matching

    CT saturation recognition

    REF differential current

    supervision

    Interturn fault protection (16)

    Based on zero sequence direction

    Self-adpative interturn fault

    detection

    A complete protection functions library,include:

    Transformer differential protection

    (87T)

    Reactor differential protection

    (87R)

    Restricted earth fault protection

    for transformer(87NT)

    Restricted earth fault protection

    for reactor(87NR)

    Inter-turn protection (16)

    Overcurrent protection (50, 51,

    67)

    Earth fault protection (50N, 51N,

    67N)

    Neutral earth fault protection (50G,51G, 67G)

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    Feature

    3

    Thermal overload protection (49)

    Overload protection (50OL)

    Delta winding overload protection(50OL)

    Overexcitation protection (24)

    Overvoltage protection (59)

    Circuit breaker failure protection

    (50BF)

    Poles discordance protection

    (50PD)

    Dead zone protection (50DZ)

    Voltage transformer secondary

    circuit supervision (97FF)

    Current transformer secondary

    circuit supervision

    2 sets external trip commands (BIs

    BOs

    Self-supervision to all modules in the

    IED

    Complete information recording:

    tripping reports, alarm reports, startup

    reports and general operation reports.

    Any kinds of reports can be stored up

    to 2000 and be memorized in case of

    power disconnection

    Up to three electric /optical Ethernet

    ports can be selected to communicate

    with substation automation system by

    IEC61850 or IEC60870-5-103

    protocols

    Up to two electric RS-485 ports can be

    selected to communicate with

    substation automation system by

    IEC60870-5-103 protocol

    Time synchronization via network

    (SNTP), pulse and IRIG-B mode

    Configurable LEDs and output relays

    satisfied users requirement

    Versatile human-machine interface

    Multifunctional software tool for setting,

    monitoring, fault recording analysis,configuration, etc.

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    Function

    4

    Protection functions

    Description ANSI CodeIEC 61850

    Logical Node

    Name

    IEC 60617

    graphical symbol

    Differential protection

    Transformer differential protection 87T PDIF

    Reactor differential protection 87R PDIF

    Restricted earth fault protection for

    transformer87NT PDIF

    Restricted earth fault protection for reactor 87NR PDIF

    Current protection

    Inter-turn fault protection 16

    Overcurrent protection 50,51,67PIOC

    PTOC

    3IINV>

    3I >>

    3I >>>

    Earth fault protection 50N, 51N, 67NPIEF

    PTEF

    I0INV>

    I0>>

    I0>>>

    Neutral earth fault protection 50G, 51G, 67G

    Thermal overload protection 49 PTTR Ith

    Overload protection 50OL PTOC 3I >OL

    Delta Winding Overload Protection 50OL

    Voltage protection

    Overexcitation protection 24 PVPH U/f>

    Overvoltage protection 59 PTOV

    3U>

    3U>>

    Undervoltage protection 27 PTUV3UBF

    I2>BF

    Dead zone protection 50DZ

    3I> DZ

    I0>DZ

    I2>DZ

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    Function

    5

    STUB protection 50STUB PTOC 3I>STUB

    Poles discordance protection 50PD RPLD

    3I< PD

    I0>PD

    I2>PD

    Secondary system supervision

    CT secondary circuit supervision

    VT secondary circuit supervision

    Other functions

    2 sets external trip commands (BIs

    BOs)

    Monitoring functions

    Description

    Auxiliary contacts of circuit breaker supervision

    Self-supervision

    Fault recorder

    Station communication

    Description

    Front communication port

    Isolated RS232 port for maintaining

    Rear communication port

    0-2 isolated electrical RS485 communication ports, support IEC 60870-5-103 protocol

    0-3 Ethernet electrical/optical communication ports, support IEC 61850 protocol or IEC 60870-5-103

    protocol

    Time synchronization port, support GPS pulse or IRIG-B code

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    Function

    6

    IED software tools

    Functions

    Reading measuring value, IED report

    Setting

    IED testing

    Disturbance recording analysis

    IED configuration

    Printing

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    Function

    7

    Application for two-winding transformer

    HV

    LV

    50

    PIOC

    3I>>>

    PTOC

    3I> 3I>>51/67

    PIEFPTEF

    51N/67N 50N

    PTTR

    Ith49

    RBRF

    3I>BF50BF

    I0>>>I0> I0>>

    PVPH

    U/f>24 27

    PTUV

    59

    PTOV

    3U< 3U>

    PVPH

    U/f>24

    PIOC

    3I>>>

    PTOC

    3I> 3I>>51/67

    PTEF

    51N/67N I0> I0>>50

    PIEF

    50N

    PTTR

    Ith49

    RBRF

    3I>BF50BF

    I0>>>

    50G51G/67G 87NT

    PDIF

    87T

    PDIF

    3Id/I

    MEASUREMENT

    MONITORING

    STATION

    COMMUNICATION

    - RS232/485

    - RJ45/FO

    - IEC61850

    - IEC60870-5-103

    Fault recording

    50DZ

    50DZ

    50STUB 3I>STUB

    PTOC

    50STUB 3I>STUB

    PTOC

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    Function

    8

    Application for three-winding transformer

    HVMV

    50

    PIOC

    3I>>>

    Ith

    3I> 3I>>51/67

    PIEF

    PTEF

    51N/67N

    50N

    PTTR

    49

    PVPH

    U/f>24

    RBRF

    3I>BF50BF I0>>>

    I0> I0>>

    50G51G/67G

    87NT

    87T

    PTOC

    PDIF

    PDIF

    3Id/I

    50BF

    50

    PIOC

    3I>>>

    PTOC

    3I> 3I>>51/67

    PIEFPTEF

    51N/67N 50N

    PTTR

    Ith49

    RBRF

    3I>BF

    I0>>>I0> I0>>

    PVPH

    U/f>24 27

    PTUV

    59

    PTOV

    3U< 3U>

    HV

    50

    PIOC

    3I>>>

    PTOC

    3I> 3I>>51/67

    PIEF

    PTEF

    51N/67N

    50N

    PTTR

    Ith49

    RBRF

    3I>BF50BF I0>>>

    I0> I0>>

    PVPHU/f>24

    50G51G/67G 87NT

    PDIF

    MEASUREMENT

    MONITORING

    STATION

    COMMUNICATION

    - RS232/485

    - RJ45/FO

    - IEC61850

    - IEC60870-5-103

    LV

    Fault

    recording

    50DZ

    50DZ

    50STUB 3I>STUB

    PTOC

    50STUB 3I>STUB

    PTOC

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    Function

    9

    Application for autotransformer

    HV

    LV

    MV

    50

    PIOC

    3I>>>

    Ith

    3I> 3I>>51/67

    PIEF

    PTEF

    51N/67N

    50N

    PTTR

    49

    PVPH

    U/f>24

    RBRF

    3I>BF50BF I0>>>

    I0> I0>>

    50

    PIOC

    3I>>>

    PTOC

    3I> 3I>>51/67

    PIEF

    PTEF

    51N/67N

    50N

    PTTR

    Ith49

    RBRF

    3I>BF50BF

    I0>>>

    I0> I0>>

    PVPH

    U/f>24

    50G51G/67G

    87NT

    87T

    PTOC

    PDIF

    27

    PTUV

    59

    PTOV

    3U< 3U>

    PDIF

    3Id/I

    PIOC

    3I>>>

    PTOC

    3I> 3I>>51/67

    PTTR

    Ith49

    RBRF

    3I>BF

    PVPH

    U/f>24

    50

    50BF

    MEASUREMENT

    MONITORING

    STATION

    COMMUNICATION

    - RS232/485

    - RJ45/FO

    - IEC61850

    - IEC60870-5-103

    PIEF PTEF

    51N/67N50N I0>>> I0> I0>>

    Fault

    recording

    50DZ

    50DZ

    50STUB 3I>STUB

    PTOC

    50STUB 3I>STUB

    PTOC

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    Function

    10

    Application for reactor

    50 3I>>>

    PIOC

    51/67 3I> 3I>>

    PTOC

    50N I0>>>

    PIEF

    51N/67N I0> I0>>

    PTEF

    49 Ith

    PTTR

    PDIF

    87R

    PDIF

    87NR

    50BF

    RBRF

    3I>BF

    50PD PD

    RPLD

    16

    50G 51G/67G

    59 3U>

    PTOV

    MONITORING

    STATION

    COMMUNICATION

    MEASUREMENT

    - RS232/485

    - RJ45/FO

    - IEC61850

    - IEC60870-5-103

    Fault recording

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    Protection

    11

    Transformer differentialprotection (87T)

    The transformer differential protection

    function is provided to protect two-winding

    transformer, three-winding transformer and

    auto-transformer in various configurations

    up to 1000 kV voltage level, with internal

    CT ratio matching, vector group and zero

    sequence current compensation. The

    following features would be applied:

    Operating characteristicFigure 1 illustrates operating characteristic

    of treble slope percent differential

    protection and instantaneous differential

    protection.

    I_TRes1

    IDiff

    IRes

    Slope3

    Slope2Slope1

    Operatingarea

    I_TDiffInst

    InstantaneousDiffoperatingarea

    I_TDiff

    I_TRes2

    Figure 1 Characteristic of transformer

    differential protection

    where:

    Idiff: Differentialcurrent

    Ires : Restrain current

    I_TDiffInst: The pickup current ofinstantaneous differential protection

    I_TDiff: The pickup current of percentagedifferential protection

    I_TRes1, I_TRes2: Restrain current setting ofbreaker point 1 and breaker point 2respectively

    Slope 1 represents the sensitivity threshold

    of the differential protection and considers

    constant error current e.g. magnetizing

    currents.

    Slope 2 takes into consideration current-

    -proportional errors which may result from

    transformation errors of the main CTs, the

    input CTs of the IED, or from erroneous

    current caused by the position of the tap

    changer in power transformer.

    In the range of high current which may give

    rise to high differential current as a result of

    CT saturation, slope 3 is applicable to

    provide more stabilization.

    The differential and restraining currents are

    calculated separately in each phase of the

    protected object. Automatic identification of

    fault location is fulfilled with recognition of

    differential and restraint current trace

    around the characteristic.

    The instantaneous differential protection isable to operate promptly regardless of the

    restraining quantity and harmonic content,

    if high current fault occurs in the protected

    zone. The instantaneous differential

    protection operating area is shaded yellow

    area shown in Figure 1, where differential

    current must be larger than I_TDiffInst

    setting.

    The treble slope percent differentialprotection uses a treble-slope dual

    break-point operating characteristic which

    make it possible to improve the restraint

    capability in case of CT saturation caused

    by serious external fault current. It further

    operates in conjunction with magnetizing

    inrush, overexcitation and CT failure

    restraint features. Furthermore, the

    integrated CT saturation detection feature

    ensures reliable blocking of percent

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    Protection

    12

    differential protection in the case of CT

    saturation caused by external fault. At the

    same time, severe internal fault can cause

    fast protection tripping.

    Automatic ratio compensation

    The input currents of the IED are converted

    automatically in relation to the power

    transformer rated currents to be matched

    with each other. As a result, matching to

    various power transformer and CT ratios is

    performed purely mathematically inside the

    IED and no external matching CT is

    required.

    Automatic vector group andzero sequence currentcompensation

    Transformers have different vector groups,

    which cause a shift of the phase angles

    between the currents flowing through their

    high medium and low voltage sides.

    Without adequate correction, this phase

    shift would cause a false differential current.

    Furthermore, the existence of the neutral

    point(s) of the power transformer has a

    great impact on the differential current

    during through fault currents.

    The IED is capable to automatically

    compensate for the adverse effect of

    various vector groups of power trans-

    -formers as well as the zero sequence

    current which may flow into the protected

    zone, depending on the condition of the

    neutral point(s). This is achieved just by

    informing the IED about the vector group of

    the power transformer, and then, all

    necessary compensations would be per-

    -formed automatically by using coefficient

    matrices programmed inside the IED. This

    simplifies application of the IED in variousconfigurations.

    Inrush restraint

    This feature is provided in the IED to

    prevent percent differential protection fromfalse tripping caused by high short-time

    magnetizing currents which may be

    present during transformer energizing

    (inrush currents).

    Two algorithms are available in the IED to

    detect inrush conditions. The first one

    operates based on 2nd harmonic stabiliza-

    -tion, whereas the second algorithm

    utilizes fuzzy wave recognition of inrush

    conditions based on the current waveform.

    Furthermore, a cross blocking feature is

    provided which can be used to set the

    protection in a way that when the 2nd

    harmonic recognition is fulfilled only in one

    phase, not only the phase with the inrush

    current, but also the remaining phases of

    percent differential protection are blocked

    for a certain duration as well.

    Overexcitation restraint

    Stabilization of percent differential

    protection function is provided against

    unwanted differential currents caused by

    transformer overexcitation. Since steady

    state overexcitation is characterized by

    odd harmonics, the 3rd or the 5th harmonic

    can be selected in the IED to recognize for

    overexcitation condition.

    Current transformer saturationsupervision

    This integrated function is capable to

    recognize CT saturation. CT saturation can

    be detected when both the 2nd and 3rd

    harmonic contents of phase currents

    amongst all phase currents are more than

    a threshold. If the CT saturation occurssimultaneously with external fault

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    Protection

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    recognition, differential protection will be

    blocked.

    Differential current supervisionIn normal operation condition, zero

    differential current is expected in each

    phase. The differential current supervision

    monitors the differential current of each

    phase. An alarm report will be given, if the

    differential current exceeds the threshold

    value for a delay time.

    Reactor differentialprotection (87R)

    The reactor differential protection function

    is provided to protect shunt reactor in

    various configurations up to 1000 kV

    voltage level, with internal CT ratio

    matching. The following features would be

    applied:

    Operating characteristic

    Figure 2 illustrates the operating

    characteristic of the treble slope percent

    differential protection and instantaneous

    differential protection.

    I_RRes1

    IDiff

    IRes

    Slope3

    Slope2Slope1

    Operatingarea

    I_RDiffInst

    InstantaneousDiffoperatingarea

    I_RDiff

    I_RRes2

    Figure 2 Characteristic of reactor differential

    protection

    where:

    Idiff: Differentialcurrent

    Ires : Restrain current

    I_RDiffInst: The pickup current ofinstantaneous differential protection

    I_RDiff: The pickup current of percentagedifferential protection

    I_RRes1, I_RRes2: Restrain current setting ofbreaker point 1 and breaker point 2respectively

    Slope 1 represents the sensitivity

    threshold of the differential protection

    and considers constant error current e.g.

    magnetizing currents.

    Slope 2 takes into consideration current-

    -proportional errors which may resultfrom transformation errors of the main

    CTs and the input CTs of the IED.

    In the range of high current which may give

    rise to high differential current as a result of

    CT saturation, slope 3 is applicable to

    provide more stabilization.

    The differential and restraining currents are

    calculated separately in each phase of the

    protected object. Automatic identification of

    fault location is fulfilled with recognition of

    differential and restraining current trace

    around the characteristic.

    The instantaneous differential protection

    is able to operate promptly regardless of

    the restraining quantity and harmonic

    content, if high current fault occurs in the

    protected zone. The instantaneous

    differential protection operating area

    shaded yellow area shown in Figure 2,

    where differential current must be larger

    than I_RDiffInst setting.

    The treble slope percent differential

    protection uses a treble-slope dual

    break-point operating characteristic with

    integrated CT saturation detection feature

    ensures reliable blocking of percent

    differential protection in the case of CT

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    Protection

    14

    saturation caused by external fault. At the

    same time, severe internal fault can cause

    fast protection tripping.

    Automatic ratio compensation

    The input currents of the IED are converted

    automatically in relation to the shunt

    reactor rated currents to be matched with

    each other. As a result, matching to various

    shunt reactor and CT ratios is performed

    purely mathematically inside the device

    and no external matching CT is required.

    Current transformer saturationsupervision

    This integrated function is capable to

    recognize CT saturation. CT saturation can

    be detected when both the 2nd and 3rd

    harmonic contents of phase currents

    amongst all phase currents are more than

    a threshold. If the CT saturation occurs

    simultaneously with external fault

    recognition, differential protection will be

    blocked.

    Differential current supervision

    In normal operation condition, zero

    differential current is expected in each

    phase. The differential current supervision

    monitors the differential current of each

    phase. An alarm report will be given, if the

    differential current exceeds the thresholdvalue for a delay time.

    Restricted earth faultprotection fortransformer (87NT)

    The REF protection provides higher

    sensitivity and higher speed when they

    measure individually on each winding.

    They are capable to detect earth faults in

    (auto) transformer earthed. A precondition

    for using these functions is that a neutral

    CT should be provided.

    Operating characteristic

    Figure 3 illustrates the dual slope operating

    characteristics of the REF.

    I0Diff

    I0Res

    I_NDiff

    Slope_NDiff

    Operatingarea

    Figure 3 Characteristic of REF protection

    where:

    I0Diff : Zero sequence differentialcurrent

    I0Res : Zero sequence restraint current

    I_NDiff: The sensitive threshold of pickupcurrent of REF protection

    Slope_NDiff: Slope of the characteristic

    Restricted earth fault currentsupervision

    In normal operation condition, zero

    sequence differential current is expected

    for restricted earth fault protection. Therestricted earth fault current supervision

    monitors differential current. An alarm is

    generated after a dropout time, if the

    restricted differential current exceeds the

    setting threshold. The alarm is given to

    draw the user attention to check the faulty

    connection and remove it in time.

    Current transformer saturation

    supervisionThis integrated function is capable to

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    Protection

    15

    recognize CT saturation. In this situation,

    CT saturation is detected when both the

    2nd and 3rd harmonic components of

    phase currents amongst all phase currentsare more than a threshold. Using these

    measurements, if the CT saturation occurs

    simultaneous with external fault

    recognition, the restricted earth fault

    protection will be blocked.

    Difference of transientcharacteristic of CTs detection

    Difference of transient characteristic ofphase or neutral CTs may result in

    zero-sequence current in REF protection

    during an external three-phase fault. To

    remove this problem, the situation is

    detected by using the calculated positive

    and zero-sequence currents. The condition

    is checked for each side of transformer

    separately.

    Restricted earth faultprotection forreactor (87NR)

    The REF protection provides higher

    sensitivity and higher speed when they

    measure individually on each winding.

    They are capable to detect earth faults in

    reactor earthed.

    Operating characteristic

    Figure 4 illustrates the dual slope operating

    characteristics of the REF as well as

    instantaneous characteristic.

    I0Diff

    I0Res

    I_NDiff

    SLOPE_NDiff

    Operating area

    I_NDiffnst

    I_NRes

    Instantaneous REF operating area

    Figure 4 Characteristic of REF protection

    where:

    I0Diff : Zero sequence differentialcurrent

    I0Res : Zero sequence restraint current

    I_NDiffInst: The pickup current ofinstantaneous REF protection

    I_NDiff: The sensitive threshold of pickupcurrent of REF protection

    I_NRes: Restrain current setting of breakerpoint

    Slope_NDiff: Slope of the characteristic

    The function can be connected with

    calculated zero-sequence current from

    neutral-point CT of main reactor or external

    measuring neutral CT.

    Restricted earth fault currentsupervision

    In normal operation condition, less to zerodifferential current is expected for

    restricted earth fault protection. The

    restricted earth fault current supervision

    monitors differential current. An alarm is

    generated after a preset time, if the

    restricted differential current exceeds the

    setting threshold. The alarm is given to

    draw the user attention to check the faulty

    connection and remove it in time.

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    Protection

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    Current transformer saturationsupervision

    This integrated function is capable torecognize CT saturation, if calculated zero

    sequence current is used from neutral side

    CT of the main reactor, instead measured

    value from the dedicated neutral CT. In this

    situation, CT saturation is detected when

    both the 2nd and 3rd harmonic components

    of phase currents amongst all phase

    currents are more than a threshold. Using

    these measurements, if the CT saturation

    occurs simultaneous with external fault

    recognition, the restricted earth fault

    protection will be blocked.

    Interturn faultprotection (16)

    The inter-turn fault protection detects faults

    between reactor winding turns. A short

    circuit of a few turns of the winding will give

    rise to a heavy fault current in the

    short-circuited loop, but the terminal

    currents will be very small, because of the

    high ratio of transformation between the

    whole winding and the short-circuited turns.

    Therefore, the short circuited turns can be

    damaged by large short circuit current. In

    this case, partial winding flashover is more

    likely and the subsequent progress of thefault, if not detected in the earliest fault

    stage, may severely destroy the object.

    The inter-turn fault protection in the IED

    uses zero-sequence component direction

    using zero-sequence current in neutral-

    -point of the main reactor and the

    calculated zero-sequence voltage at the

    HV terminal of the reactor.

    When there is inter-turn short-circuit inside

    the reactor, the zero-sequence voltage

    leads the zero-sequence current. However,

    for an external fault, the corresponding

    zero-sequence voltage will lag thezero-sequence current. So, the phase-

    -angle relation is used to distinguish the

    internal or external fault of the reactor.

    Overcurrent protection(50, 51, 67)

    The protection provides following

    features:

    Two definite time stages

    One inverse time stage

    11 kinds of IEC and ANSI inverse time

    characteristic curves as well as

    optional user defined characteristic

    Selectable directional element charac-

    -teristic angle, to satisfy the differentnetwork conditions and applications

    Each stage can be set individually as

    directional/non-directional

    Directional element can be set to point

    protected object or system for all

    stages

    Each stage can be set individually for

    inrush restraint

    Cross blocking function for inrush

    detection

    Settable maximum inrush current

    VT secondary circuit supervision for

    directional protection. Once VT failure

    happens, the directional stage can be

    set to be blocked or to be

    non-directional

    Inrush restraint function

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    Protection

    17

    The protection relay may detect large

    magnetizing inrush currents during

    transformer energizing. In addition to

    considerable unbalance fundamentalcurrent, Inrush current comprises large

    second harmonic current which doesnt

    appear in short circuit current. Therefore,

    the inrush current may affect the protection

    functions which operate based on the

    fundamental component of the measured

    current. Accordingly, inrush restraint logic

    is provided to prevent overcurrent

    protection from maloperation.

    Furthermore, by recognition of the inrush

    current in one phase, it is possible to set

    the protection in a way that not only the

    phase with the considerable inrush current,

    but also the other phases of the

    overcurrent protection are blocked for a

    certain time. This is achieved by

    cross-blocking feature integrated in the

    IED.

    The inrush restraint function has a

    maximum inrush current setting. Once

    the measuring current exceeds the

    setting, the overcurrent protection will not

    be blocked any longer.

    Characteristic of directionelement

    The direction detection is performed by

    determining the position of current vector

    in directional characteristic. In other word,

    it is done by comparing phase angle

    between the fault current and the

    reference voltage, Figure 5 illustrates the

    direction detection characteristic for A

    phase element.

    Forward

    Reverse

    UBC_Ref

    Ph_Char

    IA

    IA

    0

    90

    Figure 5 Direction detection characteristic of

    overcurrent protection directional element

    where:

    Ph_Char: The settable the characteristic angle

    The assignment of the applied measuring

    values used in direction determination has

    been shown in Table 1for different types of

    faults.

    Table 1 Assignment of applied current and

    reference voltage for directional element

    Phase Current Voltage

    A aI bcU

    Bb

    I ca

    U

    C cI abU

    For three-phase short-circuit fault,

    without any healthy phase, memory

    voltage values are used to determine

    direction clearly if the measured voltage

    values are not sufficient. The detected

    direction is based on the voltage of

    previously saved cycles.

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    Protection

    18

    Earth fault protection(50N, 51N, 67N)

    The earth fault protection can be used to

    clear phase to earth faults as system

    back-up protection.

    The protection provides following

    features:

    Two definite time stages

    One inverse time stage

    11 kinds of the IEC and ANSI inverse

    time characteristic curves as well as

    optional user defined characteristic

    Zero sequence directional element

    Each stage can be set individually as

    directional/non-directional

    Directional element can be set to be

    forward toward the protected object or

    reverse toward system for all stage

    Settable directional element

    characteristic angle, to satisfy the

    different network conditions and

    applications

    Each stage can be set individually for

    inrush restraint

    Settable maximum inrush current

    Inrush restraint function adopting 2nd

    harmonic measured phase or earth

    current settable

    VT secondary circuit supervision for

    directional protection function. Once

    VT failure happens, the directional

    stage can be set to be blocked or to be

    non-directional

    Zero-sequence current is calculated by

    summation of 3 phase currents

    Directional element

    The earth fault protection adopts zero

    sequence directional element which

    compares the zero sequence system

    quantities:

    3I0, current is calculated from the sum

    of the three phase currents

    3U0, the voltage is used as reference

    voltage. It is calculated from the sum of

    the three phase voltages

    Forward

    Reverse

    0_Char

    Bisector

    Bisector

    0_Ref3U

    0

    -3I0

    -3I090

    Figure 6 Direction detection characteristic of

    zero sequence directional element

    where:

    0_Char: The settable characteristic angle

    There are two operation areas which are

    provided for direction determination, the

    forward area toward the protected object

    and the reverse area toward the system,

    which are shown inFigure6.

    Furthermore, under the VT failure

    situation, it can be set to block directional

    earth fault protection or to apply

    non-directional earth fault protection.

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    Protection

    19

    Inrush restraint function

    The protection relay may detect large

    magnetizing inrush currents duringtransformer energizing. In addition to

    considerable unbalance fundamental

    current, Inrush current comprises large

    second harmonic current which doesnt

    appear in short circuit current. Therefore,

    the inrush current may affect the protection

    functions which operate based on the

    fundamental component of the measured

    current. Accordingly, inrush restraint logic

    is provided to prevent earth fault protection

    from mis-tripping.

    Since inrush current cannot be more than a

    specified value, the inrush restraint

    provides an upper current limit in which

    blocking does not occur.

    Neutral earth fault

    protection (50G, 51G67G)

    The neutral earth fault protection focus

    on phase to earth faults. The measuring

    current is one phase current from

    dedicated neutral CT.

    The protection function provides following

    features:

    Two definite time stages

    One inverse time stage

    11 kinds of the IEC and ANSI inverse

    time characteristic curves as well as

    optional user defined characteristic

    Each stage can be set to be

    directional/non-directional

    independently

    Zero sequence directional element. Its

    characteristic is same as earth fault

    protection illustrated inFigure 6

    Directional element can be set to be

    forward toward the protected object or

    reverse toward system for all stages

    Setable directional element

    characteristic angle, to satisfy the

    different network conditions and

    applications

    Inrush restraint function can be set for

    each stage separately

    Settable maximum inrush current

    VT secondary circuit supervision for

    directional protection function

    Neutral current is measured from

    dedicated neutral CT

    Inrush restraint feature

    The neutral earth fault protection may

    detect large magnetizing inrush currents

    flowing when transformer is energized.

    Directional element

    Directional determination of neutral earth

    fault element adopts the zero sequence

    directional element as same as the one

    applied by earth fault protection. The only

    difference is the measured current, which

    is measured from the neutral point CT

    instead of being calculated from three

    phase currents.

    Thermal overloadprotection (49)

    The insulating material surrounding the

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    Protection

    20

    windings ages rapidly if the temperature

    exceeds the design limit value. Thus, a

    thermal protection function is required to

    supplement the existing windingtemperature device. The thermal

    overload protection estimates winding

    temperature and thus prevents it from

    thermal damaging.

    The thermal overload protection operates

    based on an approximate replica of the

    temperature rise in the protected object

    caused by overload.

    The thermal replica can be implemented

    based on thermal models (Cold or Hot

    Curve) of IEC60255-8 standard.

    The thermal overload in the IED is

    provided with one trip stage as well as one

    alarm stage. It is possible to set the alarm

    stage at a certain percentage of the setting

    value applied at the trip stage.

    The calculation is performed separately foreach phase, based on fundamental

    component and harmonic components.

    Overload protection(50OL)

    The IED supervises load flow in real time.

    If each phase current is greater than the

    dedicated setting for a set delay time, the

    protection will issue alarm.

    Transformer deltawinding overloadprotection (50OL)

    When there is a dedicated CT for each

    phase of the transformer delta winding,the protection is provided to monitor the

    load flow in real time. If all three phase

    current are always greater than the

    setting of power swing for a setting time,

    the alarm will be reported.

    Overexcitationprotection (24)

    The IED provides an overexcitation

    protection to detect impermissible over-

    -excitation conditions which can

    endanger power transformers as a result

    of saturation in iron core and resultinglarge eddy current losses which may

    lead to impermissible temperature rise

    inside the transformer core.

    The function measures the voltage

    /frequency (U/f) ratio which is

    proportional to the flux density in

    transformer core.

    One definite time stage for alarm

    One definite time stage for trip

    One thermal overexcitation time

    characteristic stage, which can be

    defined by user-defined settings (see

    Figure7

    u/f

    1.05

    t(s)T10 T8 T6 T4 T2

    1.10

    1.15

    1.20

    1.25

    1.30

    1.35

    1.401.45

    1.50

    T1T3T5T7T9

    Figure 7 Thermal overexcitation time

    characteristic

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    Protection

    21

    Overvoltageprotection (59)

    One voltage rise occur possibly in the

    power system during abnormal conditions

    such as no-load, lightly load, or open line

    end on long line. The protection can be

    used as open line end detector or as

    system voltage supervision normally.

    The protection provides following features:

    Two definite time stages

    First stage can be set to alarm or trip

    Measuring voltage between phase-

    -earth voltage and phase-phase

    selectable

    Settable dropout ratio

    Undervoltage

    protection (27)One voltage reduction can occur in the

    power system during faults or abnormal

    conditions.

    The protection provides following

    features:

    Two definite time stages

    First stage can be set to alarm or trip

    Measuring voltage between phase-

    -earth voltage and phase-phase

    selectable

    Current criteria supervision

    Circuit breaker aux. contact super-

    -vision

    VT secondary circuit supervision, the

    undervoltage function will be blocked

    when VT failure happens

    Settable dropout ratio

    Breaker failureprotection (50BF)

    The circuit breaker failure protection is

    able to detect a failure of the circuit

    breaker during a fault clearance. It

    ensures fast back-up tripping of

    surrounding breakers by tripping relevant

    bus sections.

    The protection can be three-phase

    started to allow use with three phase

    tripping applications.

    Once a circuit breaker operating failure

    occurs on a feeder/transformer, the bus

    section which the feeder/transformer is

    connected with can be selectively

    isolated by the protection. In addition a

    The CBs of the other windings of the

    transformer are tripped at the same time.

    In the event of a circuit breaker failure

    with a busbar fault, a trip signal is issued

    to trip the CBs of the other windings of

    the transformer.

    The current criteria are in combination

    with three phase current, zero and

    negative sequence current to achieve ahigher security.

    The function can be set to give three phase

    re-tripping of the local breaker to avoid

    unnecessary tripping of surrounding

    breakers in the case of two available trip

    coils.

    Two trip stages (local and surrounding

    breaker tripping)

    Internal/ external initiation

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    Protection

    22

    Selectable CB Aux contacts checking

    Current criteria checking (including

    phase current, zero and negative

    sequence current)

    Dead zone protection(50DZ)

    The IED provides this protection function

    to protect dead zone, namely the area

    between circuit breaker and CT in the

    case that CB is open. Therefore, byoccurrence of a fault in dead zone, the

    short circuit current is measured by

    protection relay while CB auxiliary

    contacts indicate the CB is open.

    Internal/ external initiation

    Self-adaptive for bus side CT or line

    side CT

    Bus2

    IFAULT

    Trip

    T1

    L1Ln

    Bus1

    Bus3

    Opened CB

    Closed CB

    Legend:

    Figure 8 Tripping logic when applying bus side CT

    When one bus side CT of feeder is

    applied, once a fault occurs in the dead

    zone, the IED trips the relevant busbar

    zone. Tripping logic is illustrated inFigure 8.

    Bus2

    IFAULT

    trip

    T1

    L1Ln

    Bus1

    Bus3

    Opened CB

    Closed CB

    Legend:

    Figure 9 Tripping logic when applying transformer

    side CT

    When one transformer side CT is applied,

    when a fault occurs in the dead zone,

    protection relay trip the circuit breakers

    of the others transformer winding.

    Tripping logic is illustrated in Figure 9 .

    Poles discordanceprotection (50PD)

    The phase segregated operating circuit

    breakers can be in different positions

    (close-open) due to electrical or

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    Protection

    23

    mechanical failures during the system

    normal operation.

    The protection operates based on

    information from auxiliary contacts of the

    circuit breaker with additional criteria.

    The protection performs following

    features:

    3 phase CB Aux contacts supervision

    Current criteria checking (includingphase current, zero and negativesequence current)

    Secondary systemsupervision

    Current transformersecondary circuit supervision

    Open or short circuited CT cores can

    cause unwanted operation of some

    protection functions such as earth faultcurrent and negative sequence current

    functions.

    During the normal operation without any

    disturbance, the IED monitors the three

    phase currents of all sides of transformer.

    If only one or two phase currents drop

    down less than a threshold and the

    differential current is larger than a preset

    threshold, CT secondary circuit open isdetermined and alarm will be issued. The

    CT open alarm can be set to block

    differential protection or not.

    Voltage transformer

    secondary circuit supervision

    A measured voltage failure, due to a

    broken conductor or a short circuit fault

    in the secondary circuit of voltage

    transformer, may result in unwanted

    operation of the protection functions

    which work based on voltage criteria. VT

    failure supervision function is provided to

    block these protection functions and

    enable the backup protection functions.

    The features of the function are as

    follows:

    Symmetrical/asymmetrical VT failure

    detection

    3-phase AC voltage MCB monitoring

    1-phase AC voltage MCB monitoring

    Zero and negative sequence current

    monitoring

    Applicable in solid grounded,

    compensated or isolated networks

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    Monitoring

    24

    Self-supervision

    All modules can perform self-

    -supervision to its key hardwarecomponents and program, as soon as

    energizing. Parts of the modules are

    self-supervised in real time. All internal

    faults or abnormal conditions will

    initiate an alarm. The fatal faults among

    them will result in the whole IED

    blocked

    CPU module and communication

    module perform real time inter-

    -supervision. Therefore communication

    interruption between them is detected

    and related alarm will be given

    CRC code checks for the setting,

    program and configuration, etc.

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    Communication

    25

    Station communication

    Overview

    The IED is able to connect to one or

    more substation level systems or

    equipments simultaneously, through the

    communication ports with communica-

    -tion protocols supported. (Shown in

    Figure 9)

    Front communication port

    There is a serial RS232 port on the front

    plate of all the IEDs. Through this port,

    the IED can be connected to the

    personal computer for setting, testing,

    and configuration using the dedicated

    Sifang software tool.

    RS485 communication ports

    Up to 2 isolated electrical RS485

    communication ports are provided to

    connect with substation automation

    system. These two ports can work in

    parallel for IEC60870-5-103.

    Ethernet communicationports

    Up to 3 electrical or optical Ethernet

    communication ports are provided toconnect with substation automation system.

    These two out of three ports can work in

    parallel for protocol, IEC61850 or

    IEC60870-5-103.

    Gateway

    or

    converter

    Work Station 3

    Server or

    Work Station 1

    Server or

    Work Station 2

    Work Station 4

    Net 2: IEC61850/IEC103,Ethernet Port B

    Net 3: IEC103, RS485 Port A

    Net 4: IEC103, RS485 Port B

    Net 1: IEC61850/IEC103,Ethernet Port A

    Gateway

    or

    converter

    SwitchSwitch Switch

    Switch

    Switch

    Switch

    Figure 9 Connection example for multi-networks of station automation system

    Note: All four ports can work in parallel

    Communication protocol

    The IED supports station communication

    with IEC 61850-8 and IED60870-5-103

    protocols.

    By means of IEC61850, GOOSE

    peer-to-peer communication make it

    possible that bay IEDs can exchange

    information to each other directly, and a

    simple master-less system can be set up

    for bay and system interlocking and other

    interactive function.

    Time synchronization port

    All IEDs feature a permanently integrated

    electrical time synchronization port. It canbe used to feed timing telegrams in IRIG-B

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    Communication

    26

    or pulse format into the IEDs via time

    synchronization receivers. The IED can

    adapt the second or minute pulse in the

    pulse mode automatically.

    Meanwhile, SNTP network time synchro-

    -nization can be applied.

    Figure 10 illustrates the optional time

    synchronization modes.

    SNTP IRIG-B Pulse

    Ethernet port IRIG-B port Binary input

    Figure 10 Time synchronizing modes

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    Software Tool

    27

    A user-friendly software tool is offered for

    engineering, setting, disturbance

    analysis and monitoring. It provides

    versatile functionalities required

    throughout the life cycle of protection

    IEDs. Its features are as follows:

    Device administration in projects with

    freely configurable hierarchies for any

    substation and electrical power station

    topology

    Modification, import and export of

    parameter sets sorted by protectionfunctions,withsetting logicality check

    Precise fault analysis with visualization

    of fault records in curves, circle

    diagrams, vector diagrams, bar charts

    and data sheet.

    Intelligent plausibility checks rule out

    incorrect input

    Graphical visualization of charac-

    -teristics and zone diagrams with direct

    manipulation of the curves

    Password-protected access for

    different jobs such as parameter setting,

    commissioning and controlling

    (authorized staff only)

    Testing and diagnostic functions

    decisive support in the commissioning

    phase

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    Hardware

    28

    Front plate

    The whole front plate is divided into

    zones, each of them with a well-defined

    functionality:

    2

    1

    3

    45

    68 7

    CSC-326

    1 Liquid crystal display (LCD)

    2 LEDs

    3 Shortcut function keys

    4 Arrow keys

    5 Reset key

    6 Quit key

    7 Set key

    8 RS232 communication port

    Rear plate

    Testport

    X6

    COMX8X9X12 X1

    AIMX13

    PSM

    X2

    AIM

    X7 X3

    AIMX11 X10

    ForBIMandBOM Ethernetports

    X4

    CPU1

    X5

    CPU2

    Note: For reactor protection, X2 and X3 are not used.

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    Hardware

    29

    Modules

    Analogue Input Module (AIM)

    The analogue input module is used to

    galvanically separate and transform the

    secondary currents and voltages

    generated by the measuring transformers.

    CPU Module (CPU)

    The CPU module handles all protection

    functions and logic. There are two CPUmodules in the IED, CPU1 and CPU2, with

    the same software and hardware. They

    work in parallel and interlock each other to

    prevent maloperation due to the internal

    faults of one CPU modules.

    Moreover, the redundant A/D sampling

    channels are equipped. By comparing the

    data from redundant sampling channels,

    any sampling data errors and the channelhardware faults can be detected

    immediately and the proper alarm and

    blocking is initiated in time.

    Communication Module (COM)

    The communication module performs

    communication between the internal

    protection system and external equipments

    such as HMI, engineering workstation,

    substation automation system, RTU, etc.,

    to transmit remote metering, remote

    signaling, SOE, event reports and record

    data.

    Up to 3 channels isolated electrical or

    optical Ethernet ports and up to 2 channels

    RS485 serial communication ports can be

    provided in communication module to meetthe communication demands of different

    substation automation system and RTU at

    the same time.

    The time synchronization port is equipped,

    which can work in pulse mode or IRIG-B

    mode. SNTP mode can be applied through

    communication port.

    In addition, a series printer port is also

    reserved.

    Binary Input Module (BIM)

    The binary input module is used to connect

    the input signals and alarm signals such as

    the auxiliary contacts of the circuit breaker

    (CB), etc.

    Binary Output Module (BOM)

    The binary output modules mainly providetripping output contacts, initiating output

    contacts and signaling output contacts. All

    the tripping output relays have contacts

    with a high switching capacity and are

    blocked by protection startup elements.

    Each output relay can be configured to

    satisfy the demands of users.

    Power Supply Module (PSM)

    The power supply module is used to

    provide the correct internal voltages and

    full isolation between the terminal and the

    battery system.

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    Hardware

    30

    Dimension

    B

    A

    C

    D

    E

    Figure 11 4U, 19 case with rear cover

    Table 2 Dimension of the IED case

    Legend A B C D E

    Dimension (mm) 177 482.6 265 320 437.2

    A

    B

    C D

    E

    Figure 12 Cut-out on the panel

    Table 3 Dimension of the cutout for IED mounting

    Legend A B C D E

    Dimension (mm) 450 465 101.6 178 6.5

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    Connection

    32

    CSC-326

    X12a02

    c02a04

    c04

    a06c06

    a08c08a10c10

    a12

    c12a14

    c14

    a16c16

    a18c18a20

    c20

    a22

    c22a24

    c24a26c26

    a28

    c28a30

    c30

    a32

    c32

    X11

    a02c02a04

    c04

    a06

    c06a08

    c08a10c10

    a12

    c12a14

    c14

    a16c16

    a18c18a20

    c20

    a22

    c22a24

    c24a26c26

    a28

    c28a30

    c30

    a32

    c32

    Output relay 01

    Output relay 02

    Output relay 03

    Output relay 04

    Output relay 05

    Output relay 06

    Output relay 07

    Output relay 08

    Output relay 09

    Output relay 10

    Output relay 11

    Output relay 12

    Output relay 13

    Output relay 14

    Output relay 15

    Output relay 16

    X9

    a02c02a04

    c04

    a06

    c06a08

    c08a10c10

    a12

    c12a14

    c14

    a16c16

    a18c18a20

    c20

    a22

    c22a24

    c24a26c26

    a28

    c28a30

    c30

    a32

    c32

    Output relay 01

    Output relay 02

    Output relay 03

    Output relay 04

    Output relay 05

    Output relay 06

    Output relay 07

    X10a02

    c02

    a04

    c04

    a06

    c06

    a08c08a10c10

    a12

    c12a14

    c14a16

    c16

    a18c18

    a20

    c20

    a22

    c22a24

    c24a26c26

    a28

    c28a30

    c30

    a32

    c32

    Output relay 01

    Output relay 02

    Output relay 03

    Output relay 04Output relay 05

    Output relay 06

    Output relay 07

    Output relay 08

    Output relay 09

    Output relay 10

    Output relay 11

    Output relay 12

    Output relay 13

    Output relay 14

    Output relay 15

    Output relay 16

    1)

    Note :

    1) X12 is optional terminal

    set, for additional binary

    output module ordered by

    user.

    Output relay 08

    Output relay 09

    Output relay 10

    Output relay 11

    Output relay 12

    Output relay 13

    Output relay 14

    Output relay 15

    Output relay 16

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    Connection

    33

    CSC-326X13a02c02

    a04

    c04a06

    c06a08

    c08a10

    c10

    a12c12

    a14c14

    a16c16

    a18c18a20

    c20

    a22c22

    a24

    c24a26

    c26a28

    c28a30

    c30a32

    c32

    DC24V+output

    Null

    DC24V-output

    Powerfailurealarmrelay1

    AUXDC+input

    Powerfailurealarmrelay2

    AUXDC-input

    Null

    Null

    Null

    Terminalforearthing

    Terminalforearthing

    Null

    Null

    Null

    Null

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    Connection

    34

    B. Typical analogue inputs connection for 2 windings transformerwith 2 breakers on high and low voltage windings respectively

    a01

    a02

    a03

    b01

    b02

    b03

    *

    *

    *

    *

    A B C

    *

    *

    *

    BC

    *

    *

    *

    A B C

    *

    *

    *

    ABC

    A

    IH1A IH1B IH1C IH2C IH2B IH2A

    IH1

    IH1

    IH2

    IH1N

    IH1N

    a04

    a05

    a06

    b04

    b05

    b06

    IH2N

    IH2

    a11

    a10

    b10

    UHN

    UH

    UHAUHB

    UHC

    *

    UH

    UHA

    UHB

    UHC

    IH2N

    UHNa07 b07

    a08 b08

    IREFH

    IH1A

    IH1B

    IH1C

    IH2A

    IH2B

    IH2C

    IREFH

    IREFH

    INBKH

    INBKH

    IREFH

    INBKH

    INBKH

    IL1C IL1B IL1A

    IL1

    IL1N IL2N IL2A IL2B

    IL2

    IL2C

    a01

    a02

    a03

    b01

    b02

    b03IL1

    IL1N

    a04

    a05

    a06

    b04

    b05

    b06

    IL2N

    IL2

    IL1AIL1B

    IL1C

    IL2A

    IL2B

    IL2C

    a11

    a10

    b10

    ULN

    ULA

    ULB

    ULCUL

    b11

    b11

    IH0

    IH0

    UL

    ULAULBULCULN

    AIM 1

    AIM 2

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    Connection

    35

    C. Typical analogue inputs connection for 2 windings transformerwith 1 breaker on high and low voltage windings respectively

    * * *

    * * *

    ABC

    A

    B

    C

    a01

    a02

    a03

    b01

    b02

    b03

    IH1

    IH1N

    a11

    a10

    b10

    UHN

    UH

    UHA

    UHB

    UHC

    a07 b07

    a08 b08

    IREFH

    IH1A

    IH1B

    IH1C

    IREFH

    INBKH

    INBKH

    a01

    a02

    a03

    b01

    b02

    b03

    IL1

    IL1N

    IL1A

    IL1B

    IL1C

    a11

    a10

    b10

    ULN

    ULA

    ULB

    ULCUL

    b11

    b11

    IH0

    UH

    UHC

    UHB

    UHAUHN

    IH1A

    IH1B

    IH1CIH1

    IH1N

    *

    *

    IREFH

    IREFH

    INBKH

    INBKH

    IH0

    IL1N

    IL1A

    IL1B

    IL1C

    IL1

    ULA

    ULB

    ULCULN

    UL

    *

    *

    IREFL

    IREFL

    INBKL

    INBKL

    IL0

    a07 b07

    a08 b08

    IREFL

    IREFL

    INBKL

    INBKL

    IL0

    AIM 1

    AIM 2

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    Connection

    36

    D. Typical analogue inputs connection for 3 windings transformerwith 1 breaker on high, medium and low voltage windingsrespectively

    * * *

    * * *

    A

    BC

    A

    BC

    a01

    a02

    a03

    b01

    b02

    b03IH1

    IH1N

    a11

    a10

    b10

    UHN

    UH

    UHA

    UHB

    UHC

    a07 b07

    a08 b08

    IREFH

    IH1A

    IH1B

    IH1C

    IREFH

    INBKH

    INBKH

    a01

    a02

    a03

    b01

    b02

    b03IL1

    IL1N

    IL1A

    IL1B

    IL1C

    a11

    a10

    b10

    ULN

    ULA

    ULB

    ULCUL

    b11

    b11

    IH0

    UH

    UHCUHBUHAUHN

    IH1AIH1BIH1C IH1

    IH1N

    *

    *

    IREFH

    IREFH

    INBKH

    INBKH

    IH0

    IL1N

    IL1A

    IL1BIL1C

    IL1

    ULAULBULCULN

    UL

    A B C

    *

    *

    *

    IM1AIM1BIM1C

    IM1

    IM1N

    UM

    UMAUMBUMCUMN

    *

    *

    IREFM

    IREFM

    INBKM

    INBKM

    IM0

    a01

    a02

    a03

    b01

    b02

    b03

    IM1

    IM1N

    a11

    a10

    b10

    UMN

    UM

    UMA

    UMB

    UMC

    a07 b07

    a08 b08

    IREFM

    IM1A

    IM1B

    IM1C

    IREFM

    INBKM

    INBKM

    b11

    IM0

    AIM 1

    AIM 2

    AIM 3

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    Connection

    37

    E. Typical analogue inputs connection for 3 windings transformerwith 2 breakers on high and medium voltage winding and 1breaker on low voltage windings respectively

    a01

    a02

    a03

    b01

    b02

    b03

    *

    *

    *

    *

    A B C

    *

    *

    *

    BC

    * * *

    A B C ABC

    A

    IH1A IH1B IH1C IH2C IH2B IH2A

    IH1

    IH1

    IH2

    IH1N

    IH1N

    a04

    a05

    a06

    b04

    b05

    b06

    IH2N

    IH2

    a11

    a10

    b10

    UHN

    UH

    UHAUHB

    UHC

    *

    UH

    UHA

    UHB

    UHC

    IH2N

    UHN

    a07 b07

    a08 b08

    IREFH

    IH1A

    IH1B

    IH1C

    IH2A

    IH2B

    IH2C

    IREFH

    IREFH

    INBKH

    INBKH

    IREFH

    INBKH

    INBKH

    IL1A

    IL1B

    IL1CIL1

    IL1N

    a01

    a02

    a03

    b01

    b02

    b03

    IL1

    IL1N

    IL1A

    IL1B

    IL1C

    a11

    a10

    b10

    ULN

    ULA

    ULB

    ULCUL

    b11

    b11

    IH0

    IH0

    UL

    ULA

    ULBULCULN

    a01

    a02

    a03

    b01

    b02

    b03

    IM1N

    IM1

    a11

    a10

    b10

    UMN

    UM

    UMA

    UMB

    UMC

    IM1A

    IM1B

    IM1C

    b11

    UM

    UMAUMBUMCUMN

    * * *

    IM1A

    IM1C IM1

    IM1N

    IM1B

    * * *

    IM2A

    IM2C IM2

    IM2N

    IM2B*

    *

    IREFM

    IREFM

    INBKM

    INBKM

    IM0

    A

    BC

    A

    B

    C

    a04

    a05

    a06

    b04

    b05

    b06

    IM2N

    IM2

    IM2A

    IM2B

    IM2C

    a07 b07

    a08 b08

    IREFM

    IREFM

    INBKM

    INBKM

    IM0

    AIM 1

    AIM 2

    AIM 3

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    Connection

    39

    G. Typical analogue inputs connection for autotransformer with 2breaker on high voltage winding, and 1 breaker on medium andlow voltage windings respectively

    a01

    a02

    a03

    b01

    b02

    b03

    *

    *

    *

    *

    A B C

    *

    *

    *

    BC

    * * *

    A

    B

    C

    A

    IH1A IH1B IH1C IH2C IH2B IH2A

    IH1

    IH1

    IH2

    IH1N

    IH1N

    a04

    a05

    a06

    b04

    b05

    b06

    IH2N

    IH2

    a11

    a10

    b10

    UHN

    UH

    UHAUHBUHC

    *

    UH

    UHA

    UHB

    UHC

    IH2N

    UHN

    a07 b07

    a08 b08

    IREFH

    IH1A

    IH1B

    IH1C

    IH2A

    IH2B

    IH2C

    IREFH

    IREFH

    INBKH

    INBKH

    IREFH

    INBKH

    INBKH

    IL1A

    IL1B

    IL1C IL1

    IL1N

    a01

    a02

    a03

    b01

    b02

    b03

    IL1

    IL1N

    a04

    a05

    a06

    b04

    b05

    b06

    IL2N

    IL2

    IL1A

    IL1B

    IL1C

    IL2A

    IL2B

    IL2C

    a11

    a10

    b10

    ULN

    ULA

    ULB

    ULCUL

    b11

    b11

    IH0

    IH0

    UL

    ULAULBULCUHN

    A B C

    *

    *

    *

    IM1A IM1B IM1CIM1N

    UM

    UMAUMBUMC UMN

    IM1

    a01

    a02

    a03

    b01

    b02

    b03

    IM1N

    IM1

    a11

    a10

    b10

    UMN

    UM

    UMA

    UMB

    UMC

    IM1A

    IM1B

    IM1C

    b11

    AIM 1

    AIM 2

    *

    *

    *

    IG1C IG1BIG1A

    IG

    IG1N

    a04

    a05

    a06

    b04

    b05

    b06

    IG1N

    IG1A

    IG1BIG1C

    IG

    AIM 3

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    Connection

    40

    H. Typical analogue inputs connection for reactor applicationwith all CTs

    * * *

    * * *

    IHA

    IHB

    IHC

    Protection IED

    a01

    a02

    a03

    b01

    b02

    b03

    ILA

    ILB

    ILC

    a04

    a05

    a06

    b04

    b05

    b06

    * 3IH0a07b07

    *

    a08

    b08 3IL0

    UHB

    UHA

    UHCUHN

    a10

    a09

    b09

    b10

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    Connection

    41

    I. Typical analogue inputs connection for reactor applicationwith three-phase CTs on HV and LV side of reactor

    * * *

    * * *

    IHA

    IHB

    IHC

    Protection IED

    a01

    a02

    a03

    b01

    b02

    b03

    ILA

    ILB

    ILC

    a04

    a05

    a06

    b04

    b05

    b06

    UHB

    UHA

    UHC

    UHN

    a10

    a09

    b09

    b10

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    Connection

    42

    J. Typical analogue inputs connection for reactor applicationwith three-phase CTs on HV side of main reactor and singlephase CT of neutral point reactor (near grounding)

    * * *

    IHA

    IHB

    IHC

    Protection IED

    a01

    a02

    a03

    b01

    b02

    b03

    *

    a08

    b08 3IL0

    UHB

    UHA

    UHC

    UHN

    a10

    a09

    b09

    b10

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    Connection

    43

    K. Typical analogue inputs connection for reactor applicationwith three-phase CTs on HV side of main reactor and singlephase CT of neutral point reactor (near main reactor)

    * * *

    IHA

    IHB

    IHC

    Protection IED

    a01

    a02

    a03

    b01

    b02

    b03

    * 3IH0

    a07

    b07

    UHB

    UHA

    UHCUHN

    a10

    a09

    b09

    b10

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    Technical data

    44

    Frequency

    Item Standard Data

    Rated system frequency IEC 60255-1 50 Hz or 60Hz

    Internal current transformer

    Item Standard Data

    Rated current Ir IEC 60255-1 1 or 5 ANominal current range 0.05 Irto 30 Ir

    Nominal current range of sensitive

    CT

    0.005 to 1 A

    Power consumption (per phase) 0.1 VA at Ir= 1 A; 0.5 VA at Ir= 5 A

    0.5 VA for sensitive CTThermal overload capability IEC 60255-1

    IEC 60255-27

    100 Ir for 1 s

    4 Ircontinuous

    Internal voltage transformer

    Item Standard Data

    Rated voltage Vr(ph-ph) IEC 60255-1 100 V /110 V

    Nominal range (ph-e) 0.4 V to 120 V

    Power consumption at Vr= 110 V IEC 60255-27

    DL/T 478-2001

    0.1 VA per phase

    Thermal overload capability

    (phase-neutral voltage)

    IEC 60255-27

    DL/T 478-2001

    2 Vr, for 10s

    1.5 Vr, continuous

    Auxiliary voltage

    Item Standard Data

    Rated auxiliary voltage Uaux IEC60255-1 110 to 250VPermissible tolerance IEC60255-1 %20 UauxPower consumption at quiescent

    state

    IEC60255-1 50 W per power supply module

    Power consumption at maximum

    load

    IEC60255-1 60 W per power supply module

    Inrush Current IEC60255-1 T 10 ms/I 25 A per power supply

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    Technical data

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    module,

    Binary inputs

    Item Standard Data

    Input voltage range IEC60255-1 110/125 V220/250 V

    Threshold1: guarantee

    operation

    IEC60255-1 154V, for 220/250V

    77V, for 110V/125V

    Threshold2: uncertain operation IEC60255-1 132V, for 220/250V ;

    66V, for 110V/125V

    Response time/reset time IEC60255-1 Software provides de-bouncetime

    Power consumption, energized IEC60255-1 Max. 0.5 W/input, 110VMax. 1 W/input, 220V

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    Technical Data

    46

    Binary outputs

    Item Standard Data

    Max. system voltage IEC60255-1 250V /~

    Current carrying capacity IEC60255-1 5 A continuous,

    30A200ms ON, 15s OFF

    Making capacity IEC60255-1 1100 W( ) at inductive load with

    L/R>40 ms

    1000 VA(AC)

    Breaking capacity IEC60255-1 220V , 0.15A, at L/R40 ms

    110V , 0.30A, at L/R40 ms

    Mechanical endurance, Unloaded IEC60255-1 50,000,000 cycles (3 Hz switching

    frequency)

    Mechanical endurance, making IEC60255-1 1000 cycles

    Mechanical endurance, breaking IEC60255-1 1000 cycles

    Specification state verification IEC60255-1

    IEC60255-23

    IEC61810-1

    UL/CSATV

    Contact circuit resistance

    measurement

    IEC60255-1

    IEC60255-23

    IEC61810-1

    30m

    Open Contact insulation test (AC

    Dielectric strength)

    IEC60255-1

    IEC60255-27

    AC1000V 1min

    Maximum temperature of parts and

    materials

    IEC60255-1 55

    Front communication port

    Item Data

    Number 1

    Connection Isolated, RS232; front panel,

    9-pin subminiature connector, for software tools

    Communication speed 9600 baud

    Max. length of communication cable 15 m

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    Technical Data

    47

    RS485 communication port

    Item Data

    Number 0 to 2

    Connection 2-wire connector

    Rear port in communication module

    Max. length of communication cable 1.0 km

    Test voltage 500 V AC against earth

    For IEC 60870-5-103 protocol

    Communication speed Factory setting 9600 baud,

    Min. 1200 baud, Max. 19200 baud

    Ethernet communication port

    Item Data

    Electrical communication port

    Number 0 to 3

    Connection RJ45 connector

    Rear port in communication module

    Max. length of communication cable 100m

    For IEC 61850 protocol

    Communication speed 100 Mbit/s

    For IEC 60870-5-103 protocol

    Communication speed 100 Mbit/s

    Optical communication port ( optional )

    Number 0 to 2

    Connection SC connector

    Rear port in communication module

    Optical cable type Multi-mode

    Max. length of communication cable 2.0km

    IEC 61850 protocol

    Communication speed 100 Mbit/s

    IEC 60870-5-103 protocol

    Communication speed 100 Mbit/s

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    Technical Data

    48

    Time synchronization

    Item DataMode Pulse mode

    IRIG-B signal format IRIG-B000

    Connection 2-wire connector

    Rear port in communication module

    Voltage levels differential input

    Environmental influence

    Item Data

    Recommended permanent operating temperature -10 C to +55C

    (Legibility of display may be impaired above

    +55 C /+131 F)

    Storage and transport temperature limit -25C to +70C

    Permissible humidity 95 % of relative humidity

    IED design

    Item Data

    Case size 4U19inchWeight 10kg

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    Technical Data

    49

    Product safety-related Tests

    Item Standard Data

    Over voltage category IEC60255-27 Category III

    Pollution degree IEC60255-27 Degree 2

    Insulation IEC60255-27 Basic insulation

    Degree of protection (IP) IEC60255-27

    IEC 60529

    Front plate: IP40

    Rear, side, top and bottom: IP 30

    Power frequency high voltage

    withstand test

    IEC 60255-5

    EN 60255-5

    ANSI C37.90

    GB/T 15145-2001

    DL/T 478-2001

    2KV, 50Hz

    2.8kV

    between the following circuits:

    auxiliary power supply

    CT / VT inputs

    binary inputs

    binary outputs

    case earth

    500V, 50Hz

    between the following circuits:

    Communication ports to case

    earth

    time synchronization terminalsto case earth

    Impulse voltage test IEC60255-5

    IEC 60255-27

    EN 60255-5

    ANSI C37.90

    GB/T 15145-2001

    DL/T 478-2001

    5kV (1.2/50s, 0.5J)

    If Ui63V

    1kV if Ui

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    Technical Data

    50

    Protective bonding resistance IEC60255-27 0.1

    Fire withstand/flammability IEC60255-27 Class V2

    Electromagnetic immunity tests

    Item Standard Data

    1 MHz burst immunity test IEC60255-22-1IEC60255-26

    IEC61000-4-18

    EN 60255-22-1

    ANSI/IEEE C37.90.1

    Class III

    2.5 kV CM ; 1 kV DM

    Tested on the following circuits:

    auxiliary power supply

    CT / VT inputs

    binary inputs

    binary outputs

    1 kV CM ; 0 kV DM

    Tested on the following circuits:

    communication portsElectrostatic discharge IEC 60255-22-2

    IEC 61000-4-2

    EN 60255-22-2

    Level 4

    8 kV contact discharge;

    15 kV air gap discharge;

    both polarities; 150 pF; Ri= 330

    Radiated electromagnetic field

    disturbance testIEC 60255-22-3

    EN 60255-22-3

    Frequency sweep:

    80 MHz 1 GHz; 1.4 GHz 2.7 GHz

    spot frequencies:

    80 MHz; 160 MHz; 380 MHz; 450

    MHz; 900 MHz; 1850 MHz; 2150

    MHz

    10 V/m

    AM, 80%, 1 kHzRadiated electromagnetic field

    disturbance testIEC 60255-22-3

    EN 60255-22-3

    Pulse-modulated

    10 V/m, 900 MHz; repetition rate

    200 Hz, on duration 50 %

    Electric fast transient/burst immunity

    testIEC 60255-22-4,

    IEC 61000-4-4

    EN 60255-22-4

    ANSI/IEEE C37.90.1

    Class A, 4KV

    Tested on the following circuits:

    auxiliary power supply

    CT / VT inputs

    binary inputs

    binary outputs

    Class A, 1KV

    Tested on the following circuits:

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    Technical Data

    51

    communication ports

    Surge immunity test IEC 60255-22-5

    IEC 61000-4-5

    4.0kV L-E

    2.0kV L-L

    Tested on the following circuits:

    auxiliary power supply

    CT / VT inputs

    binary inputs

    binary outputs

    500V L-E

    Tested on the following circuits:

    communication ports

    Conduct immunity test IEC 60255-22-6

    IEC 61000-4-6

    Frequency sweep: 150 kHz 80

    MHz

    spot frequencies: 27 MHz and 68

    MHz

    10 V

    AM, 80%, 1 kHz

    Power frequency immunity test IEC60255-22-7 Class A

    300 V CM

    150 V DM

    Power frequency magnetic field test IEC 61000-4-8 Level 430 A/m cont. / 300 A/m 1 s to 3 s

    100 kHz burst immunity test IEC61000-4-18 2.5 kV CM ; 1 kV DMTested on the following circuits:

    auxiliary power supply

    CT / VT inputs

    binary inputs

    binary outputs

    1 kV CM ; 0 kV DMTested on the following circuits:

    communication ports

    DC voltage interruption test

    Item Standard Data

    DC voltage dips IEC 60255-11 100% reduction 20 ms

    60% reduction 200 ms

    30% reduction 500 ms

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    Technical Data

    52

    DC voltage interruptions IEC 60255-11 100% reduction 5 s

    DC voltage ripple IEC 60255-11 15%, twice rated frequency

    DC voltage gradual shutdown

    /start-up

    IEC 60255-11 60 s shut down ramp

    5 min power off

    60 s start-up ramp

    DC voltage reverse polarity IEC 60255-11 1 min

    Electromagnetic emission test

    Item Standard Data

    Radiated emission IEC60255-25

    EN60255-25

    CISPR22

    30MHz to 1GHz ( IT device may up

    to 5 GHz)

    Conducted emission IEC60255-25

    EN60255-25

    CISPR22

    0.15MHz to 30MHz

    Mechanical tests

    Item Standard Data

    Sinusoidal Vibration response

    test

    IEC60255-21-1

    EN 60255-21-1

    Class 1

    10 Hz to 60 Hz: 0.075 mm

    60 Hz to 150 Hz: 1 g

    1 sweep cycle in each axis

    Relay energized

    Sinusoidal Vibration endurance

    test

    IEC60255-21-1

    EN 60255-21-1

    Class 1

    10 Hz to 150 Hz: 1 g

    20 sweep cycle in each axis

    Relay non-energized

    Shock response test IEC60255-21-2

    EN 60255-21-2

    Class 1

    5 g, 11 ms duration

    3 shocks in both directions of 3 axes

    Relay energized

    Shock withstand test IEC60255-21-2

    EN 60255-21-2

    Class 1

    15 g, 11 ms duration

    3 shocks in both directions of 3 axes

    Relay non-energized

    Bump test IEC60255-21-2 Class 1

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    Technical Data

    53

    10 g, 16 ms duration

    1000 shocks in both directions of 3

    axes

    Relay non-energized

    Seismic test IEC60255-21-3 Class 1

    X-axis 1 Hz to 8/9 Hz: 7.5 mm

    X-axis 8/9 Hz to 35 Hz :2 g

    Y-axis 1 Hz to 8/9 Hz: 3.75 mm

    Y-axis 8/9 Hz to 35 Hz :1 g

    1 sweep cycle in each axis,

    Relay energized

    Climatic tests

    Item Standard Data

    Cold test - Operation IEC60255-27

    IEC60068-2-1

    -10C, 16 hours, rated load

    Cold test Storage IEC60255-27 IEC60068-2-1 -25C, 16 hours

    Dry heat test Operation [IEC60255-27

    IEC60068-2-2

    +55C, 16 hours, rated load

    Dry heat test Storage IEC60255-27IEC60068-2-2

    +70C, 16 hours

    Change of temperature IEC60255-27

    IEC60068-2-14

    Test Nb, figure 2, 5 cycles

    -10C / +55C

    Damp heat static test IEC60255-27

    IEC60068-2-78

    +40C, 93% r.h. 10 days, rated load

    Damp heat cyclic test IEC60255-27

    IEC60068-2-30

    +55C, 93% r.h. 6 cycles, rated load

    CE Certificate

    Item Data

    EMC DirectiveEN 61000-6-2 and EN61000-6-4 (EMC Council

    Directive 2004/108/EC)

    Low voltage directive EN 60255-27 (Low-voltage directive 2006/95 EC).

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    Functions

    NOTE:Ir: CT rated secondary current, 1A or 5A;

    Transformer differential protection (ANSI 87T)

    Item Range or value Tolerance

    Instantaneous differential current 0.5 Ir to 20.00 Ir 3% setting or 0.02IrPercentage differential current 0.08 Ir to 4.00 Ir 3% setting or 0.02Ir,

    Restraint current 1 0.1 Ir to 1 Ir 3% setting or 0.02Ir

    Restraint current 2 0.1 Ir to 10 Ir 3% setting or 0.02Ir

    Slope 1 0.0 to 0.2

    Slope 2 0.2 to 0.7

    Slope 3 0.25 to 0.95

    2nd harmonic restraint ratio 0.05 to 0.80 of fundamental

    3rd / 5th harmonic restraint ratio 0.05 to 0.80

    Reset ratio of restraineddifferential

    approx. 0.7

    Operating time of restraintdifferential

    30ms at 200% setting, andIDifferential>2IRestraint

    Operating time of instantaneousdifferential

    20ms typically at 200% setting

    Reset time approx. 40ms

    Reactor differential protection (ANSI 87R)

    Item Range or value Tolerance

    Instantaneous differential current 0.5 Ir to 20.00 Ir 3% setting or 0.02IrPercentage differential current 0.05 Ir to 4.00 Ir 3% setting or0.02Ir,

    Restraint current 1 0.1 Ir to 1 Ir 3% setting or 0.02Ir

    Restraint current 2 0.1 Ir to 10 Ir 3% setting or 0.02Ir

    Slope 1 0.0 to 0.2Slope 2 0.2 to 0.7

    Slope 3 0.25 to 0.95

    Operating time of restraintdifferential

    30ms at 200% setting, andIDifferential>2IRestraint

    Operating time of instantaneousdifferential

    20ms typically at 200% setting

    Reset time approx. 40ms

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    Restricted earth fault protection for transformer (ANSI-87NT)

    Item Rang or Value Tolerance

    Differential current 0.08 Ir to 2.00 Ir 3% setting or 0.02IrSlope 0.2 to 0.95

    Time delay0.00 to 60.00s, step 0.01s 1% setting or +40ms, at 200%

    operating setting

    Reset ratio Approx. 0.7, at tripping

    Operating time 30ms, at 200% setting

    Reset time approx. 40ms

    Restricted earth fault protection for reactor (ANSI-87NR)

    Item Rang or Value Tolerance

    Instantaneous differential current 0.1 Ir to 20.00 Ir 3% setting or 0.02Ir

    Differential current threshold 0.03 Ir to 20.00 Ir 3% setting or 0.02IrRestraint current 1 0.05 Ir to 20.00 Ir 3% setting or 0.02Ir

    Slope 0 to 10

    Differential current alarm 0.05 Ir to 2.00 Ir 3% setting or 0.02Ir

    Alarm time delay0.00 to 60.00s, step 0.01s 1% setting or +40ms, at 200%

    operating setting

    Reset ratio Approx. 0.7, at tripping

    Operating time 30ms, at 200% setting

    Reset time approx. 40ms

    Inter-turn fault protection (ANSI 16)

    Item Rang or Value Tolerance

    Transverse differential protection of single element

    Current 0.08 Ir to 10.00 Ir 5% setting or 0.02IrTime delay after rotor singleearth fault

    0.10 to 1.00s, step 0.01s 1% setting or +50ms, at 200%operating setting

    Filtering ratio of the 3r

    harmonic

    >100

    Reset time approx. 40ms

    Reset ratio Approx. 0.95 when I/In 0.5

    zero-sequence voltage protection blocked by negative-sequence directional element

    Zero sequence voltage ofstage 1 3.00 to 100.00 V 2.5% setting or 0.05VZero-sequence voltage ofstage 2 1.00 to 100.00 VTime delay of stage 1 0.10 to 30.00s, step 0.01s 1% setting or +40ms, at 200%

    operating settingTime delay of stage 2 0.10 to 30.00s, step 0.01s

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    The most sensitive angle ofnegative sequence directionalelement

    82.55

    Operating range of negative

    sequence directional element

    0~165

    Filtering ratio of the 3r

    harmonic

    >100

    Negative-sequence directional inter-turn protection

    fault component of negativesequence current

    0.02 Ir to 1.00 Ir 5% setting or 0.02Irfault component of negativesequence voltage

    0.5V to 10V 2.5% setting or 0.05V

    The most sensitive angle of

    steady-state component

    82.55

    Minimum operating

    negative-sequence increment

    < 0.5% nS at the most sensitive

    angle.

    nS : rated secondary capacity

    volume of generator.

    Operating range of negativesequence directional element

    0~165

    Operating time

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    Extremely inverse;

    Definite inverse

    user-defined characteristicT=

    5% setting + 40ms, at 2

    1VCharacteristic angle 0 to 90, step 1

    Earth fault protection (ANSI 50N, 51N, 67N)

    Item Rang or value Tolerance

    Definite time characteristic

    Current 0.08 Ir to 20.00 Ir 3% setting or 0.02IrTime delay 0.00 to 60.00s, step 0.01s

    1% setting or +40ms, at 200%operating setting

    Reset time approx. 40ms

    Reset ratio Approx. 0.95 at I/Ir 0.5

    Inverse time characteristics

    Current 0.08 Ir to 20.00 Ir 3% setting or 0.02IrIEC standard Normal inverse;

    Very inverse;

    Extremely inverse;

    Long inverse

    IEC60255-151

    5% setting + 40ms, at 2

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    Breaker failure protection (ANSI 50 BF)

    Item Rang or Value Tolerance

    phase current

    Negative sequence current

    zero sequence current

    0.08 Ir to 20.00 Ir 3% setting or 0.02Ir

    Time delay of stage 1 0.00s to 32.00 s, step 0.01s 1% setting or +25 ms, at

    200% operating settingTime delay of stage 2 0.00s to 32.00 s, step 0.01s

    Reset ratio >0.95

    Reset time of stage 1 < 20ms

    Dead zone protection (ANSI 50DZ)

    Item Rang or Value Tolerance

    Current 0.08 Ir to 20.00 Ir 3% setting or 0.02IrTime delay 0.00s to 32.00s, step 0.01s 1% setting or +40 ms, at

    200% operating setting

    Reset ratio >0.95

    Pole discordance protection (ANSI 50PD)

    Item Rang or Value Tolerance

    Current 0.08 Ir to 20.00 Ir 3% setting or 0.02IrTime delay 0.00s to 60.00s, step 0.01s 1% setting or +40 ms, at

    200% operating setting

    Reset ratio >0.95

    Overexcitation protection (ANSI 24)

    Item Rang or Value Tolerance

    Reference voltage UN 40 to 130V, 3 % setting or 1 V

    Inverse time characteristic

    Ratio: 1.00 to 1.50 2.5% of the setting or 0.01

    Time delay 0.1s to 9999s 5% setting or70ms

    Pair of Values for characteristicof V/f

    1.05 /1.10 /1.15 /1.20 /1.25 /1.30/1.35 /1.40 /1.45 /1.50

    5% setting or 70ms

    Reset time, Approx. 70ms

    Reset ratio 0.96

    Definite time characteristic

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    Time delay T 0.1s to 9999s5% setting or70ms, at 200%operating setting

    Reset time, Approx. 70ms

    Reset ratio 0.96

    Undervoltage protection (ANSI 27)Item Rang or Value Tolerance

    Voltage connection Phase-to-phase voltages or

    phase-to-earth voltages

    3 % setting or 1 V

    Phase to earth voltage 5 to 75 V , step 1 V 3 % setting or 1 V

    Phase to phase voltage 10 to 150 V, step 1 V 3 % setting or 1 V

    Reset ratio 1.01 to 2.00, step 0.01 3 % setting

    Time delay 0.00 to 120.00 s, step 0.01 s 1 % setting or +50 ms, at 80%

    operating setting

    Current criteria 0.08 to 2.00 Ir 3% setting or0.02Ir

    Reset time 50 ms

    Overvoltage protection (ANSI 59)

    Item Rang or Value Tolerance

    Voltage connection Phase-to-phase voltages or

    phase-to-earth voltages 3 % setting or 1 V

    Phase to earth voltage 40 to 100 V, step 1 V 3 % setting or 1 V

    Phase to phase voltage 80 to 200 V, step 1 V 3 % setting or 1 V

    Reset ratio 0.90