[object xmldocument] transformer protection terminal

7/29/2019 [object XMLDocument] Transformer Protection Terminal

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7UDQVIRUPHUSURWHFWLRQWHUPLQDO 5(7&1MRK 504 042-BEN

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Configurable logic with inputs and outputs,

AND-, OR-, INV-, SR-gates, timers and triplogic for trip and/or indication of external

protection features (Buchholz, tempera-ture, etc.) are available using the CAP-tool

Display of service values

Display of event records and trip values

Continuous self monitoring and diagnostics

Disturbance recording and data storage for

presentation on PC

Menu driven front display with key pad andport connector for PC

Remote data communication with up to 2

ports for station control and station monitor-

ing systems

Available for 19 inch rack mounting in a

panel, surface or flush mounting

Hardware:

- Two analog input modules with9I & 1U inputs

- One binary input module, one binary

output module and one mA analog inputmodule (4-20 mA)

Hardware options:

- Separate Combitest test switch for reli-

able and safe testing

- On/Off switch for dc supply

- Mounting details for IP 40 and IP 54

$SSOLFDWLRQ The numerical transformer terminal RET521-C3 is designed for fast and selective pro-tection and control of three-winding trans-formers, auto-transformers, generator-transformer blocks and shunt reactors.

The RET 521-C3 has low requirements onthe main Current Transformers and no inter-posing CTs are necessary.

Flexibility is provided to cover for different

applications in form of transformer size, vec-tor groups and system neutral earthing. Forbig and important transformers such as gener-ator-transformer blocks or large auto trans-formers two RET 521-C3 can be used toobtain redundancy.

Using programmable logic provides a verycompact design for protection and control.For changes in the programmable logic theCAP-tool is required.

The RET 521-C3 includes setting adaptationto power transformer rating and instrument

transformer ratios to allow protection settingsin percent (%), of the power transformer rat-ing, thus facilitating the protection settings.

The RET 521-C3 can be applied for 3-wind-ing applications as indicated in Figure 1:

Figure 1: CT group arrangement for differential pro-tection and other protections

Figure 2: An application example

ZLQGLQJDSSOLFDWLRQV

3-winding power trans-

former with all three

windings connected

3-winding power trans-

former with 2 circuit

breakers and 2 CT-sets

on one side

REF

DIFFP,REF

REF

TOV

TOV

3Id/I

Id

Id

Id

U

U

Logic

Comm.

DIFP, REF

OVEX

VCTR

I/O

TRIP en04000095.vsd

REF, DIFP

REF

HV

LV

MV


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7UDQVIRUPHUGLIIHUHQWLDOSURWHFWLRQIRUWKUHHZLQGLQJV',)3The differential protection for three windingsis one of the most important functions for fastand selective protection of transformers. TheRET 521-C3 is provided with internal adapta-tion for CT ratio matching and vector groupcompensation, which allows connectiondirectly to Y-connected main CTs. Zerosequence current elimination is made inter-nally but can alternatively be turned off. Allcurrent inputs are provided with restraint fea-tures, making the RET 521-C3 suitable formultibreaker arrangements. The setting facili-ties cover for application of the differentialprotection to power transformers with orwithout tap changer and for multi-breaker

arrangements. An adaptive differential fea-ture is included for through-faults. By intro-ducing the tap changer position to RET 521-C3, the differential protection pick-up can beset to optimum sensitivity covering low levelinternal fault currents.

Stabilization is included to avoid differentialprotection tripping for inrush currents and foroverexcitation. Stabilization is also includedfor system recovery inrush and CT saturationfor external faults. Crossblocking betweenphases is normally used, but it can alterna-tively be turned off.

A fast high set unrestrained differential cur-rent protection is also included for high speedtripping at high internal fault currents.

Service values for differential currents, biascurrent and tap position are available.

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Three units of the restricted earth fault protec-tion are included.

REF is an instantaneous earth current differ-ential protection for solidly or low impedanceearthed systems. It is applied for each trans-former winding. The protection is a stabilizedlow impedance type and is unaffected byinrush currents or external faults. The protec-tion is also stabilized against CT saturation. Adirectional feature and adaptive 2nd harmonicrestraining is included in the protection.

Service values for differential current andbias current are available.

6LQJOHSKDVHWLPHGHOD\HG09RYHUYROWDJHSURWHFWLRQ729A single-phase time delayed overvoltage pro-tection is included.

The overvoltage protection is recommendedas backup for sustained system overvoltages.The overvoltage protection is provided withtwo settable voltage levels, and both levelsare provided with definite time delay. Thelow stage can alternatively have an inversetime delay.

Service values for the highest phase voltageis available.

7LPHGHOD\HG/9QHXWUDOYROWDJHSURWHF

WLRQ729A time delayed neutral voltage protection isincluded.

The above described single-phase overvolt-age protection is also suitable as neutral over-voltage protection. The overvoltageprotection measures the fundamental fre-quency component and is therefore insensi-tive for 3rd and higher harmonics. When usedas a neutral overvoltage protection it is typi-cally connected to a VT in the neutral of thetransformer or to an open delta connection ofthe secondary windings of a three-phase set

of VTs. As a neutral overvoltage protection itis normally used in high impedance earthedsystems, and is given a longer time delay thanthe feeder earth fault protections.

2YHUH[FLWDWLRQSURWHFWLRQ9+]29(;An overexcitation protection is included inRET 521-C3.

The overexcitation protection is based onvoltage/frequency (V/Hz) measurement. TheIEEE trip time inverse characteristic can beset to follow the transformer characteristic

and a cooling time memory is included. Thetrip time characteristic is also provided withdefinite minimum and maximum times.

As an alternative a transformer adapted timedelay characteristic can be set and used forclose adaptation to the transformer capabilitycharacteristic.

Separate trip and alarm outputs are included.

Service values for relative excitation statusvoltage/frequency, thermal status and time-to-trip are available.


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9ROWDJHFRQWUROIRUDVLQJOHWUDQVIRUPHU9&75The voltage control function included in RET521-C3 is used to maintain the user presetvoltage at the low voltage side of the trans-former, i.e. at the busbar or at the feeder ends.Constant voltage is obtained by controllingthe tap changer position by raise and lowercommands. The delay for the regulating com-mand can be of inverse or definite type.Blocking is included for overcurrent and und-ervoltage, power system emergencies and tapchanger end positions. Line drop compensa-tion is included. A load shedding based onvoltage reduction is also included. A built-inpower measuring function can be used to cre-ate selectivity with other equipment influenc-

ing on the system voltage. Number of tapchanger operations can be recorded for deter-mining the service intervals. Remote or localcommand possibilities are included. Alarmsfrom the tap changer auxiliary equipment(binary contacts) can be connected to thevoltage control function. The tap changerposition is monitored by 4-20 mA-inputs tothe voltage control function. (17 positions areconsidered in the configuration).

If the number of tap position are other than17, the tap position number on the MIMblock in the configuration has to be changedby use of the CAP-tool.

Service values for busbar voltage, compen-sated voltage, actual set voltage, load voltageadjustment, tap changer position, contact lifecalculation and no of operation counter areavailable

,QSXWWULSPDWUL[External contacts, e.g. from transformer over-temperature devices and Buchholz gas detec-tor, can be connected via Binary Inputs.Logic can be arranged for alarm, event log-

ging and tripping. For redundancy reasons itis recommended to route tripping from theBuchholz or overpressure device in parallel toRET 521-C3.

7ULSSLQJPDWUL[The tripping commands are configured to triplogic blocks, which then are configured to thetripping output relays. Each trip logic block(OR gate) has 16 inputs. 4 trip logic blocksare used in the standard configuration. Anadditional 9 blocks are available using theCAP-tool.

&RQILJXUDEOHORJLFConfigurable logic elements in the form of 40AND-gates, 40 OR-gates, 20 inverters, 25timers, 20 pulse elements and 10 SR-gates areavailable. Some are already used in the con-figuration and the rest can be combined tosuit particular requirements using the CAP-tool.

7HUPLQDOGLDJUDPTerminal diagrams for the connection of theanalog inputs, the binary inputs/outputs, thelogical circuits and the protection modules,the control modules and the monitoring mod-ules are shown in Terminal diagrams onpage 16 and forward.

3DUDPHWHUVHWWLQJVRET 521-C3 has wide setting facilities toensure application flexibility. Factory defaultsettings are chosen to indicate typical settingvalues or choices. The settings are organizedas general settings and settings for each sepa-rate function.

The main data (ratings) of the protected trans-former and ratios of the instrument transform-ers are entered in the terminal setting andconfiguration menus. Most of the settingparameters of the particular functions canthen be made as per unit (p.u.) or percent (%)

values related to the power transformer rat-ing. For some protection functions there alsoexist a possibility to define the rated value inthe setting menu to another value than thepower transformer rating. Most timers are setin seconds. There is a possibility to enter oneto four complete groups of settings. It is theneasy to switch between these groups locallyor from remote.

Settings can be changed from the frontHuman-Machine-Interface (HMI), or by aportable personal computer (PC), with a

parameter setting program (PST), included inCAP 540, connected to a fibre-optic connec-tor socket at the front, or from another loca-tion over a data communication system.

,QGLFDWLRQVHYHQWVDQGVHUYLFHYDOXHVOperation indications and time-tagged eventsare available from the front HMI or a con-nected PC and from another location over adata communication system. Actual inputquantity values, load, differential current andother service values can also be read from theterminal.


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'LVWXUEDQFHUHFRUGLQJSampled data from a disturbance, like a trip-ping operation, can be stored and made avail-able for oscillographic presentation andevaluation on a front connected PC or fromanother location over a data communicationsystem, to which the disturbance files aretransferred. This function stores continu-ously sampled data in a cyclic buffer. At

selectable trigger conditions the data arestored, so that both prefault and fault data aresaved.

'DWDFRPPXQLFDWLRQTwo remote communication ports for SPAand LON can be included. They enable co-operation with a station monitoring system(SMS) including a remotely located PC, and astation control system (SCS).

'HVLJQ The physical design of terminal RET 521-C3is in line with the products in the REx 500-series. It is housed in painted sheet steelenclosure suitable for different mounting byuse of particular mounting accessories. Wire

connections are made at the rear side at termi-nals of compression type tightened by ascrew. Fibre optic wires for data communica-tion are also connected at the rear side. On thefront is a HMI-panel and socket with an opticinterface for a specific cable to a portable PC.

Behind the front there is an interconnectionboard, a motherboard, to which printed boardassemblies (PBAs) are plugged in from therear side. The input module for analog ACquantities is fixed mounted and the connec-tion terminal for these circuits are also fixedmounted. The connection terminals for theDC contact circuits are of the multipoledetachable type so as to facilitate disconnec-tion for exchange of PBAs.

The following modules are included in theRET521-C3 terminal:

Two analog input modules for 9 currentsand 1 voltage with galvanic separation andadaptation of the AC signals. The analoginput modules also contain analog to digi-

tal converters (A/D-converter) which pro-vide the necessary conversion and somefiltering.

Processor modules with data processingfor the protection as well as other func-tions and communication. As an optiontwo communication interfaces can beadded for connection to a station monitor-ing system (SMS) including a remotelylocated PC and a station control system(SCS).

Power supply module with DC/DC con-verter for the electronic circuits.

One binary input module, BIM, with 16binary inputs and one binary output mod-ule, BOM, with 24 output relay contactsare included.

One mA-analog input board with 6 chan-nels for 4-20 mA is included.

The front HMI panel includes three light-emitting diodes (LEDs), one LCD displaywith 4 lines times 16 characters. There isalso a six button key pad and a fibre-opticconnector socket, for connection to theserial port of a portable PC by means of aspecial interface cable.


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R h v S h r q h y r I v h y h t r P r h v r h t r

Current

Burden

Ir = 1 A or 5 A

< 0.25 VA at Ir

(0.2-30) x Ir(0.2-4) x Ir continu-

ously

(0.03 - 100) x Ir100 x Ir for 1 s*

AC voltage Ph-Ph**

Burden

Ur = 100/110/115/120 V

< 0.2 VA at Ur

80-120% of Ur 1.5 x Ur continuously

2.5 x Ur for 1 s

Frequency fr = 50/60 Hz 2.5 Hz 5 Hz

Frequency with extended

range fr = 50/60 Hz (0.7-1.2) x fr (0.65-1.25) x fr

Auxiliary DC voltage EL

power consumption

(terminal equipped with all

IO-modules)

Auxiliary DC power in-rush

EL = 24 - 60 V

EL = 90 - 250 V

< 35 W

220 VDC,


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9 r r q r p r X v u v v h y h t r X v u v r h v r h t r

Ambient temperature -10 C to +55 C 0.01%/ C

Frequency dependence (without

extended frequency range)

fr 2.5 Hz for 50 Hz

fr 3.0 Hz for 60 Hz

3.0%

Harmonic frequency dependence for

2:nd 3:rd and 5:th harmonic

10, 20 and 50% harmonic con-

tent of Irr

1.0%

Auxiliary DC voltage (24 -60) Vdc 20%

(110 -250) Vdc 20%

0.01% / %

Ripple in auxiliary DC voltage 12% of EL 0.01% / %

Interruption in auxiliary DC voltage

without resetting

correct function

(24 -60) Vdc 20%

(110 -250) Vdc 20% < 50 ms

0 -

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1 MHz burst disturbance 2.5 kV IEC 60255-22-1, Class III

Electrostatic discharge

Direct application 8 kV, air discharge

6 kV, contact discharge

IEC 60255-22-2, Class III

Fast transient disturbance 4 kV IEC 60255-22-4, Class A

Surge immunity test 1-2 kV, 1.2/50 s, high energy IEC 61255-22-5

Power frequency immunity test 100-300 V, 50 Hz IEC 60255-22-7, Class A

Power frequency magnetic field test 1000 A/m, 3 sec. IEC 61000-4-8, Class V

Radiated electromagnetic field

disturbance

10 V/m, (80-1000) MHz IEC 60255-22-3

Radiated electromagnetic field

disturbance

10 V/m, 80-1000 MHz,

1.4-2.0 GHz

IEC 61000-4-3, Class 3

Conducted electromagnetic field

disturbance

10 V (0.15-80) MHz IEC 60255-22-6

Radiated electromagnetic field distur-

bance

10V/m, 27, 80, 150, 450, 900

MHz

IEEE/ANSI C37.90.2

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Electromagnetic emission radiated 30-1000 MHz, class A IEC 60255-25

Electromagnetic emission conducted 0.15 - 30 MHz, class A IEC 60255-25

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Dielectric test 2.0 kV ac 1 min. IEC 60255-5

Impulse voltage test 5 kV, 1.2/50 s, 0.5 J IEC 60255-5

Insulation resistance > 100 Mohm at 500 V dc IEC 60255-5


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U r S r s r r p r h q h q

Immunity EN 61000-6-2

Emissivity EN 61000-6-4

Low voltage directive EN 50178

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Vibration Class I IEC 60255-21-1

Shock and bump Class I IEC 60255-21-2

Seismic Class I IEC 60255-21-3

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A p v h v U v h q v t h y r y h

A h v t h y r y h

h h y y r y r r q r y h

Max. system voltage 250 V ac, dc 250 V ac, dc

Test voltage across open contact,

1 min. 1.0 kV rms 800 V, dc

Current carrying capacity

continuous

1 s

8 A

10 A

8 A

10 A

Making capacity at inductive loadwith L/R > 10 ms

0.2 s

1.0 s

30 A

10 A

0.4 A

0.4 A

Breaking capacity for ac, cos > 0.4 250 V/8.0 A 250 V/8.0 A

Breaking capacity for dc

with L/R < 40 ms

48 V/1 A

110 V/0.4 A

220 V/0.2 A

250 V/0.15 A

48 V/1 A

110 V/0.4 A

220 V/0.2 A

250 V/0.15 A

Maximum capacitive load 10 nF

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8 r p r S h r q y h t r

H h v

h r h r h

H h v y h q

p v

H h v y h q

Voltage connectors 250 V AC 2.5 mm2

2 x 1 mm210 A 30 A

Current connectors 250 V AC 4 mm2 20 A 500 A

Fiber connectors

LON, SPA

Glass: Bayonet ST

Plastic: Snap in Simplex Latching


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Weight approximate 10 kg

Dimensions

Width

Height

Depth

336 mm (3/4 of 19)

6U = 267 mm

245 mm

Water and dust protection level Front IP 40 (IP 54 with sealing strip)

Sides IP 30

Back IP 20

Storage temperature -40C to +70C

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A p v W h y r

Protocol SPA

Communication speed 9600, 19200, 38400, 57600 or 115200 Bd

Slave number 1 to 899

Connectors special electric/optic cable

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A p v W h y r

Protocol SPA

Communication speed 300, 1200, 2400, 4800, 9600, 19200 or 38400 BdSlave number 1 to 899

Connectors and optical fibres glass or plastic

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A p v W h y r

Protocol LON

Communication speed 1.25 Mbit/s

Connectors and optical fibres glass or plastic

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A p v W h y r

Time tagging resolution 1 ms

Event buffering capacity

Max. number of events/

disturbance report

Max. number of disturbance reports

Time tagging error with synchronization

using LON and minute pulse

Time tagging error without synchronization

150

10

1 ms typical

10ms/hour


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A p v I v h y h t r

Frequency (0.7 -1.2) x fr acc 2 mHz at three phase connection

acc 50 mHz at single phase connection

Current (0.1 - 4.0) x Ir

Voltage (0.1 - 1.5) x Ur

Angles 0.0 - 359.9 degrees

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A p v T r v t h t r

Number of binary inputs 48

Number of analog inputs 10

Sampling rate 1 kHz or 1.2 kHz for 50 and 60 Hz respectively

Recording bandwidth (5-500) Hz or (6-600) Hz fixed

Over triggering (0.00-50.00) x rated value (Ur orIr)

Under triggering (0.00-2.00) x rated value (Ur orIr)

Pre-fault time (10-300) ms in steps of 10 ms

Post fault time (100-3000) ms in steps of 100 ms

Limit time (500-4000) ms in steps of 100 ms

Number of recorded disturbances Max. 10 disturbances

A p v W h y r

Voltage channelsdynamic range

resolution

accuracy at rated frequency frUUrU>Ur

(0.01-2.0) x Ur at 100 V sec.

0.1% of Ur

1% of Ur1% of U

Current channels

dynamic range

without DC offset

with full DC offset

resolution

accuracy at rated frequency frIIrI>Ir

(0.01-85) x Ir(0.01-40) x Ir0.25% of Ir

1% of Ir1% of I (current value)

Total recording time with 10 analog and

48 digital signals recorder maximum 40 s

Built-in calendar For 30 years including leap years

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R h v Q h h r r W h y r S h t r

Rated power 2 winding Sr 0.1-9999.9 MVA

Rated power 3 winding primary wind Sr1 0.1-9999.9 MVA

Rated power 3 winding secondary wind Sr2 0.1-9999.9 MVA

Rated power 3 winding tertiary wind Sr3 0.1-9999.9 MVA

Rated current primary winding in A Ir1 1-99999 A


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Rated current secondary winding in A Ir2 1-99999 A

Rated current tertiary winding in A Ir3 1-99999 A

Rated voltage primary winding in kV Ur1 1.0-999.9 kV

Rated voltage secondary winding in kV Ur2 1.0-999.9 kV

Rated voltage tertiary winding in kV Ur3 1.0-999.9 kV

Vector group compensation

(For different groups, Yy0, Yd1, Dy11.. etc.)

VectorGrp2WV 1-24

Vector group compensation

(For different groups, Yy0d1.. etc.)

VectorGrp3WV 1-288

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Used input tap for CT on AIM card in A InputCTTap Input 1A / Input 5A

Rated CT primary current in A CTprim 1-99999

Rated CT secondary current in A CTsec 1-5 (step 1)

Current transformer earthing, Towards power

transformer/Towards bus

CTstarpoint ToObject, FromObject

Rated VT primary voltage in kV VTprim 0.1-999.9

Rated VT secondary voltage in V VTsec 1-999

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A p v Q h h r r W h y r S h t r

Current bias CharactNo Selectable characteristics

Inrush Stabilization setting StabByOption Wave form and second

harmonic selections

Inrush restraint I2/I1ratio 5-25%

Overexcitation restraint I5/I1ratio 10-50%

Basic diff. current, % of object Ir Idmin 10-50%

High, non-restraint diff. current, % of object Ir Idunre 200-2500%

Zero Sequence Current Subtraction ZSCSub Off/On

Operation crossblocking CrossBlock Off/On

Number of taps NoOfTaps 1 - 64

Rated tap RatedTap 1 - 64

Voltage for minimum tap (tap1) in kV MinTapVoltage 0.1 - 999.9

Voltage for maximum tap in kV MaxTapVoltage 0.1 - 999.9

Operate time

at diff. current I = 2 x Irat diff. current I = 10 x Irat diff. current I = 2 x Idunre

34 ms, typically

30 ms, typically

20 ms, typically

Reset time Typical 15 ms

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Basic diff. current, % of object Ir Idmin 5-50%

Directional

characteristic

rca (fixed)

roa

18060 to 90

Operate time at 2 Id Typical 25 ms


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Operate voltage, % of object Ur

Time characteristics

UsetLow

CurveType

5.0-200.0%

Definite (Independent)Very Inverse (Dependent)

Definite time setting tDefLow 0.00-300.00 s

Inverse time characteristic

t=(k T)/[(U/Us1) -1]Us1 = UsetLow

Time multiplier

Definite minimum time

k

tMin

Very Inverse

T=13.5; =1.0

0.05-1.10

0.05-1.00 s

High set voltage, % of object Ur

Time setting

UsetHigh

tDefHigh

5.0-200.0%

0.00-300.00 s

Resetting ratio > 0.99

Operate time

IEC curves

Definite time setting

Class 5 and -0/+40ms

0.5% of setting -0/+40ms


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The Time Overvoltage Protection is used for this application

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Emax continous no-load Emaxcont 1.00-1.50 p.u.

Emax when time according to

delay tMin takes over

Emax 1.20-1.80 p.u.

Minimum time delay when over

excitation >Emax

tMin 0.50-30.00 s

Maximum time delay for over excitation tMax 10-120 min.

IEEE time characteristics

t=(k 0.18)/[M -1]2

M = overexcitation

Time multiplier for inverse time functions k 1-60

Transformer cooling time constant Tcool 1-120 min.Time delay for alarm tAlarm 0-120 s


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Time value in sec. for Time 1 t1 0-7200 s






Operate time 5% of setting -0/+40 ms

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Voltage control set voltage, % of Ur2* Uset 85.0-120.0%

acc < 0.5% of Ur

Set voltage deadband, % of Ur2 Udeadband 0.5-9.0%

Set inner deadband, % of Ur2 UdeadbandInner 0.1-9.0%

Upper limit busbar voltage Umax 80-180%

acc < 0.5% of Ur

Lower limit busbar voltage Umin 70-120%

acc < 0.5% of Ur

Fast step down function activation FSDMode Off, Auto, AutoMan

Time characteristic for Time 1

(first command)

t1Use Const

Inverse

Time delay for first command t1 1-300 s

Time characteristic for Time 2

(consecutive command)

t2Use Const

Inverse

Time delay for consecutive command t2 1-300 s

Minimum operating time in sec tMin 1.0-30.0 s

Operation line voltage drop compensation OperationLDC Off/On

Regulation for capacitive load OperCapaLDC Off/On

Line resistance, primary values Rline 0.0-150.0 ohm

Line reactance, primary values Xline -150.0 to 150.0 ohm

Constant load voltage adjust factor 1 LVAConst1 -9.0 to 9.0%




Load current dependent automatic voltage

reduction factor

VRAuto -4.0 to 4.0%

Undervoltage blocking, % of Ur2 Ublock 50-90%

Operation OLTC reversed action blocking OperationRA Off/On

Power system emergency blocking time tRevAct 30-360 s

Tap changer low l imit position

Setting 0 is for special configuration of auto

block feature

LowVoltTap 0 and 1-64

Tap changer high limit position

Setting 0 is for special configuration of auto

block feature

HighVoltTap 0 and 1-64

Overcurrent blocking, % of object Ir1 Iblock 0-250%

Output pulse duration tPulseDur 0.5-5.0 s

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Figure 3: RET 521-C3 terminal function configuration

Tap changer constant timeout time tTCTimeout 1-60 s

Operate level for Active Power in forward

direction of Power monitoring function

Pforw -9999.99-9999.99 MW

Operate level for Active Power in reverse


Prev -9999.99-9999.99 MW

Operate level for Reactive Power in forward


Qforw -9999.99-9999.99 MvAr

Operate level for Reactive Power in reverse


Qrev -9999.99-9999.99 MVAr

Power monitoring function time delay tPower 1-60 s

Hunting detection alarm, max operation/day DayHuntDetect 0-100

Hunting detection alarm, max operation/hour HourHuntDetect 0-30

Time sliding window hunting detection tHuntDetect 1-120 min.Hunting detection alarm, max operation/wind NoOpWindow 3-30

Contact life counter factor CLFactor 1.0 -3.0

Initial value tap changer life counter InitCLCounter 0-9999999

External MMI operation priority mode ExtMMIPrio Priority/No Priority

Total block of the voltage control function TotalBlock Off/On

Automatic mode block of the voltage control AutoBlock Off/On

*) Rated secondary side power transformer voltage set in menu Transformer data

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S @ U $ ! 8 "

LV 59N-1&2

TOV2

87T/87H

DIFP

DR01

DR02

DR03

DR04

DR10

AIM1

DR05

DR06

DR07

DR08

DR09

AIM2

C W f T D

/

C W f T D

/

C W f T D

/

C W f T ! D

/

C W f T ! D

/

C W f T ! D

/

C W D

1

T Q 6 S @

T Q 6 S @

H W V

/ /

H W D

/

H W D

/

H W D

/

G W D

/

G W D

/

G W D

/

H W D

1

G W D

1

T Q 6 S @

G W " V

2

HV 87N

REF1

MV 87N

REF2

LV 87N

REF3

VCTR-Single

OVEX

MV 59-1&2

TOV1

90

24

H v v t A p v h y v

Disturbance Recorder for 10 marked analogue inputs

Event Recorder for 48 binary signals

H W D

/

D

/

D

/

D

5

C W 7 V T 7 6 S !

C

W

f

T

!

D

/

D

/

D

/

D

5

C W 7 V T 7 6 S

C

W

f

T

D

/

D

/

D

/

D

5

H W 7 V T 7 6 S

H W D

1

G

W

D

1

C W D

1

G W D

/

D

/

D

/

D

5

H W V

/ /

G W " V

2

T

Z

!

T

R

!

T

Z

!T

Z

!

T

R

!T

R

!

en04000087.vsd


15/24


Page 15

The numbers (50, 87 etc.) used in figure 3 arein accordance with the standardIEEE C 37.2 - 1991. Table 25 gives a short

overview of used numbers and the particularfunctions within RET 521 which fulfills thatfunctionality:

7DEOH 'HVFULSWLRQRI,(((QXPEHUV

D @ @ @ I i r 9 r p v v

24 Overexcitation (V/Hz) protection. Function name in RET 521 terminal is OVEX.

59

59N

Overvoltage protection with two stages. First stage with inverse or definite time

delay. Second stage definite time delay only. Time delay can be set to zero. Functions

with this functionality in RET 521 terminal are TOV1 & TOV2. These functions can be

used as LV overvoltage or open delta overvoltage protection.

87T/87H Transformer differential protection with two operating stages. First stage is

restrained against inrush currents and transformer overexcitation. Second stage is

unrestrained (instantaneous). Function with this functionality in RET 521 terminal is

DIFP. This function can be used as transformer, autotransformer or reactor differen-

tial protection.

87N Restricted earth fault (ground fault) protection for power transformer winding.Functions with this functionality in RET 521 terminal are REF1, REF2 and REF3.

These functions can be used as restricted earth fault protection for individual power

transformer winding.

90 Automatic power transformer voltage (on-load tap-changer) control. Function with

this functionality in RET 521 terminal is VCTR for single transformer. This function

can be used for automatic transformer OLTC position regulation. Function includes

line drop compensation, overcurrent blocking, undervoltage blocking, etc.


16/24


Page 16

7HUPLQDOGLDJUDPV

Figure 4: Three Winding Transformer protection Terminal

1

AI 1(I)

AI 2(I)

AI 3(I)

AI 4(I)

AI 5(I)

AI 6(I)

AI 7(I)

AI 8(I)

AI 9(I)

AI 10(U)

X31

2

56

87

9

10

1718

192021

222324

25

X81:TX

INTERNAL FAIL

+

-EL

P3

1)

2)

FIBREOPTIC

X82:RX

X83:TX

TX

RXHMI3)

P8 SLM

LON CH INTERFACE

SERIAL CH INTERFACE

HMI

X141:3

X141:2

X141:1

P14

+ -

X141:4

X141:5

NC

NO4)

X121:7

X121:8

X121:9

X121:10

X121:11

X121:12

X121:13

X121:14

X121:15

X121:16

X121:17

X121:18

MI.11

MI.12

MI.13

MI.14

MI.15

MI.16

P12

+

-

5)

3

4

1112

131415

16

27

28

30

1A5A

1A5A

1A5A

1A5A

1A5A

1A5A

1A5A

X84:RX

P8

L1 L2 L3

L1L2L3

en04000089.vsd

1) COMMUNICATION PORT TO SCSOR SMS WHEN INCLUDED.

2) COMMUNICATION PORT TO SCSWHEN LON IS INCLUDED.

3) OPTICAL PORT FROM LOCAL MMLCONNECTION MADE WITH A SPECIALINTERFACE CABLE.

4) INTERNAL FAIL.

5) TAP POSITION READING .

L1 L2 L3

1AI 1(I)

AI 2(I)

AI 3(I)

AI 4(I)

AI 5(I)

AI 6(I)

AI 7(I)

AI 8(I)

AI 9(I)

AI 10(U)

X71

2

56

87

9

10

1718

192021

2223

2425

P7

3

4

1112

131415

16

27

28

30

1A5A

1A5A

1A5A

1A5A

1A5A

1A5A

1A5A

L1L2L3

LV 3I0

LV 3U0

1A5A

261A5A


17/24


Page 17

1mrk004531-cc_9.eps

1mrk004531-cc_10.eps


18/24


Page 18

1mrk004531-cc_12.eps


19/24


Page 19

2UGHULQJ RET 521-C3 terminals are intended for three-winding transformer applications. The analogtransformer input module type AIM has 10 input transformers each. 2 analog input modules areincluded. RET 521-C3 occupies 3/4 of a 6U 19 inch rack.

6RIWZDUHEDVLFIXQFWLRQVFrequency measurement function, (FRME)

Service value reading, SVR

Event recording and trip value recording (in disturbance report), ER

Custom logic programming (40 AND, 40 OR, 20 inverters, 25 timers, 20 pulse timers, 10 SR-gates and 3 MOVE blocks) is included and available using the CAP-tool, CL1

Trip logic with 12 blocks is included and available using the CAP-tool, TL

Binary converter, BC

Event function (single and double indications), EV

Command function (single and multiple), CD and CM

2UGHULQJ1XPEHU 1MRK 004 530-CD 4XDQWLW\

%DVLFGDWD

Nominal frequency: 50/60 Hz

Rated VT input voltage(across each individual

input)

100/3, 110/3, 115/3, 120/3, 100, 110, 115, 120 V

Rated CT input current 1/5 A


20/24


Page 20

3URWHFWLRQDQGFRQWUROIXQFWLRQVLQFOXGHGLQ5(7&

Transformer differential protection for three windingsTransformer differential protection 9 D A Q

Restricted earth fault protection

First restricted earth fault protection S @ A

Second restricted earth fault protection S @ A !

Third restricted earth fault protection S @ A "

Single-phase time delayed overvoltage protection or time delayed

neutral voltage protectionFirst time delayed overvoltage protection U P W

Second time delayed overvoltage protection U P W !

Overexcitation protection

Overexcitation protection P W @ Y

Single transformer voltage control (On-load tap changer control)

Voltage control W 8 U S

Disturbance recorder

Disturbance recorder 9 S


21/24


Page 21

+DUGZDUHLQFOXGHGLQ5(7&

BIM = 16 Optocoupler Inputs. Please specify rated voltage of optocoupler inputs belowBOM = 24 Contact OutputsMIM = 6 analog (i.e. mA) inputs

Please specify with X mark the selected alternative

6&6DQG606FRPPXQLFDWLRQFDSDELOLWLHV

Two AIMs9I+1U in

position

OneBinary In

module in

position

OneBinary Out

module in

position

One mAinput

module in

position

Intended fortransformer

with

PowerSupply

Module

P3, P7 P9 P10 P12 3 windings P14

3600RGXOHAuxiliary dc voltage EL

24-60 V 1MRK 002 239-AA

90-250 V 1MRK 002 239-BA

6 h v y h i y r h r q W y h t r s P p y r D 7 D H

24/30 V dc

1MRK 000 508-DB

48/60 V dc

1MRK 000 508-AB

110/125 V dc

1MRK 000 508-BB

220/250 V dc

1MRK 000 508-CB

Input/Output Module 1

(Located in Slot P9)

6 h v y h i y r v

SPA = Plastic

LON = Plastic

1MRK 001 608 -AA

SPA = Plastic

LON = Glass

1MRK 001 608-BA

SPA = Glass

LON = Glass

1MRK 001 608-CA

Rear communication via SPA

& LON bus


22/24


Page 22

0HFKDQLFDORSWLRQV

U r v p u

COMBITEST test switch module RTXP 1MRK 000 371-EA

Current circuits connected for rated

current

1 A 5 A

On/Off switch for the dc-supply RK 795 017-AA

I P U @

The test switch have internal star point connection for three-phase CT groups

Each analogue input module AIM is connected to its own test switch module so two test switches are

needed if two analogue input modules are used. The first test switch module RTXP 24 will be mounted with

the transformer protection terminal in RHGS 6 case with window door forming a full 19 case. The second

test switch module RTXP 24 (if needed) will be mounted in a separate RHGS 6 case with window door.

Test switch module RTXP24 for AIM2

mounted in RHGS6 Case

1MRK 000 371-EB

Rated current (1 or 5 A) to be specified for the connection between test switch and terminal. The terminal is

reconnectable and can at any time be altered between 1 or 5 A, but the terminal will be delivered with all

current channels connected to either 1 A or to 5 A.

0RXQWLQJGHWDLOV

Mounting details with IP40 degree of protection for the front of the protection terminal case and if neededthe extra test switch case for a second test switch module:.

Protection

terminal

Second

test

switch

case

19 rack mounting of 3/4 of 19 terminal

casing

1MRK 000 020-BA

19 rack mounting (applicable for terminal

together with test switch)

1MRK 000 020-CA

19 rack mounting for second test switch

case

1 MRK 000 020-BE

Wall mounting (applicable for terminal

and for test switch)

1MRK 000 020-DA

Flush mounting (applicable for terminal

and for test switch)

1MRK 000 020-Y

Flush mounting with IP54 (applicable for

terminal only)

1MKC 980 001-2

A p r p v p h i y r

Front connection cable between LCD-HMI and PC for termi-

nal handling (Opto/9-pole D-sub connectors)

Quantity: 1MKC 950 001-2


23/24


Page 23

5HODWHG

GRFXPHQWV

6DPSOH

VSHFLILFDWLRQ

Numerical transformer protection and controlterminal type RET 521-C3 with continuousself monitoring and analogue/digital conver-sion of all input quantities.

The terminal is suitable for protection, con-trol and monitoring of three-winding trans-formers, auto-transformers, generator-transformer block units and also for applica-tions with multi-breaker arrangements. Thenumerical transformer terminal is designed tooperate correctly over a wide frequency rangeto accommodate for system frequency varia-tions during generator start-up or shut-down.

The differential protection for three windings

is provided with adaptive 2nd harmonic andWaveblock restraint features to avoid tripping

at magnetizing inrush and 5th harmonicrestraint to avoid tripping at overexcitation.The differential protection has a settablerestraint characteristic and is provided withan adaptive differential feature for multi-breaker arrangements. The differential func-tion is stable for external faults followed byheavy CT saturation and recovery inrush.Tap-changer position indication is used toprovide maximum sensitivity for the differen-tial protection. A high-set unrestrained differ-ential current protection is included.

Three restricted earth fault protections, a sin-gle-phase time delayed overvoltage protec-tion, a time delayed neutral voltage protection

and an overexcitation protection are includedin the RET521-C3.

0DQXDOV

One User Documentation CD-ROM with all 500 series manuals is always delivered with each terminal

S y r ) T r p v s u r i r s r h 8 9 r r r q Quantity: 1MRK 002 270-AA

S y r ) T r p v s u r i r s v r q h h y r r r q

Operators manual Quantity: 1MRK 504 039-UEN

Technical reference manual Quantity: 1MRK 504 036-UEN

Installation and commissioning manual Quantity: 1MRK 504 038-UEN

Application manual Quantity: 1MRK 504 037-UEN

&XVWRPHUIHHGEDFN

For our reference and statistics we would be pleased if we are provided with the following application data:

Country: End user:

Station name: Voltage level: kV

Transformer Rated Power: MVA

U r p u v p h y r v r i p u r

CAP 540*1.3, terminal tool box 1MRK 511 142-BEN

Accessories for REx 5xx 1MRK 514 009-BEN

COMBITEST Test system 1MRK 512 001-BEN

Auxiliary relays 1MRK 508 015-BEN


24/24


Page 24

Voltage regulation for single transformer withOn-Load-Tap-Changer is also included in theRET 521-C3 numerical transformer terminal.

The terminal is provided with a preconfiguredand type tested programmable logic for tripand indications and configuration of theincluded protection, control and monitoringfunctions. Modules for binary inputs andbinary outputs to facilitate user adaptationand a mA transducer input module areincluded.

The terminal is provided with a frontmounted menu driven human-machine-inter-face and a front port optical connector for a

personal computer. Service value display ofvoltage, currents, frequency, event recordingwith 150 events and 10 recordings, and dis-turbance recording with 10 analogue signalsand 48 digital signals for 40 s, and local datastorage are available. Communication withthe terminal is provided with two ports forLON and SPA in the rear for station controland station monitoring purpose.

0DQXIDFWXUHU $%%$XWRPDWLRQ7HFKQRORJLHV$%Substation Automation

SE-721 59 Vsters

SwedenTelephone: +46 (0) 21 34 20 00

Facsimile: +46 (0) 21 14 69 18

Internet: www.abb.com/substationautomation

[object xmldocument] transformer protection terminal

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