B90 Bus Differential Relay and Breaker Failure Protection

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B90 Bus Differential Relay and Breaker Failure Protection

• Cost-efficient• Good performance• Modern communications capability• Member of the Universal Relay (UR) family• Easy integration with other URs• Common configuration tool for all B90 IEDs• Proven algorithms (B30) and hardware (UR) • Expandable• Two levels of scalability (modules and IEDs)

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NEW!

Busbar Protection Schemes

• High-impedance / linear couplers– non-configurable busbars– cheap relay, expensive primary equipment

• Blocking schemes for simple busbars• Analog low / medium - impedance schemes• Digital relays for small busbars• Digital relays for large busbars• Phase-segregated cost-efficient digital relays

for large busbars

B90

B30

BUS

PVD

Any

SPD

GE offer Approach

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Why Digital Bus Relay?

• Re-configurable busbars require dynamic assignment of currents to multiple zones– expensive and dangerous when done externally on

secondary currents (analog way)– natural and safe when done “in software”

• Breaker Fail for re-configurable busbars is naturally integrated with the bus protection

• No need for special CTs (cost)• Relaxed requirements for the CTs (cost)• Advantages of digital technology

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Design Challenges for Digital Busbar Relays

• Reliability • Security:

– Immunity to CT saturation– Immunity to wrong input information

• Large number of inputs and outputs required:– AC inputs (tens or hundreds)– Trip rated output contacts (tens or hundreds)– Other output contacts (tens)– Digital Inputs (hundreds)

• Large processing power required to handle al the data

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Traditionally Two Distinctive Architectures are Offered

• Fits better new installations

• Perceived less reliable

• Slower

52

DAU

52

DAU

52

DAU

CU

copper

fiber

Distributed Bus Protection

52 52 52

CU

copper

Centralized Bus Protection

• Fits better retrofit installations

• Perceived more reliable

• Potentially faster

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iA, vA

New Architecture – Digital Phase-Segregated Busbar Scheme

• Foundation: – Single-phase IEDs for primary

differential protection– Separate IEDs for Breaker

Failure and extra I/Os– Inter-IED communications for

sharing digital states– Scalability and flexibility

Phase A Protection

TRIPA

iB, vBPhase B

ProtectionTRIPB

iC, vCPhase C

ProtectionTRIPC

Breaker Failure

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B90 Capacity

• Up to 24 circuits in a single zone without voltage supervision

• Multi-IED architecture with each IED built on modular hardware

• Up to 24 AC inputs per B90 IED freely selectable between currents and voltages (24+0, 23+1, 22+2, ..)

• Up to 96 digital inputs per B90 IED• Up to 48 output contacts per B90 IED• Flexible allocation of AC inputs, digital inputs and

output contacts between the B90 IEDs

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B90 Features and Benefits

• Maximum number of circuits in one zone: 24• Number of zones : 4• Busbar configuration: No limits• Sub-cycle tripping time• Security (only 2msec of clean waveforms required for stability)• Differential algorithm supervised by CT saturation detection and

directional principle• Dynamic bus replica, logic and signal processing• No need for interposing CTs (ratio matching up to 32:1)• CT trouble per each zone of protection• Breaker failure per circuit• End fault protection (EFP) per circuit• Undervoltage supervision per each voltage input• Overcurrent protection (IOC and TOC) per circuit• Communication, metering and recording

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B90 Applications

• Busbars:– Single– Breaker-and-a-half– Double– Triple– With and without transfer bus

• Networks:– Solidly grounded– Lightly grounded (via resistor)– Ungrounded

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B90 Architecture Overview

• Phase-segregated multi-IED system built on Universal Relay (UR) platform

• Each IED can be configured to include up to six modules:– AC inputs (up to 3 x 24 single phase inputs)– Contact outputs (up to 6 x 8)– Digital Inputs (up to 6 X 16)– Variety of combinations of digital inputs and output

contacts• Fast digital communications between the IEDs for

sharing digital states

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B90 Architecture

B90Phase A Protection

PS

UR #1

CP

U

CO

MM

S

DS

PI/

OD

SP

I/O

DS

PI/

O

phase A currents & voltages

fiber

, rin

g co

nfig

urat

ion

phase A trip contacts

PS

CP

U

UR #2 Phase B Protection

DS

PI/

OD

SP

I/O

DS

PI/

O

CO

MM

S

phase B currents & voltages

phase B trip contacts

PS

CP

U

UR #3 Phase C Protection

DS

PI/

OD

SP

I/O

DS

PI/

O

CO

MM

S

phase C currents & voltages

phase C trip contacts

PS

CP

U

UR #4 Bus Replica & Breaker FailI/

OI/

OI/

OI/

OI/

OI/

O

CO

MM

S

• No A/C data traffic• No need for sampling

synchronization, straightforward relay configuration - all A/C signals “local” to a chassis

• Data traffic reduced to I/Os• Direct I/Os (similar to existing

UR Remote I/Os) used for exchange of binary data

• Oscillography capabilities multiplied (available in each IED separately)

• Programmable logic (FlexLogic) capabilities multiplied

• SOE capabilities multiplied• Extra URs in a loop for more

I/Os

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B90 Components: Protection IEDs

• Modular architecture (from 2 to 9 modules)• All modules but CPU and PS optional• Up to 24 AC inputs total (24 currents and no

voltages, through 12 currents and 12 voltages)

• Three I/O modules for trip contacts or extra digital inputs

• Features oriented towards AC signal processing (differential, IOC, TOC, UV, BF current supervision)

Po

wer S

up

ply

CP

U

DS

P 1

I/O

DS

P 2

I/O

DS

P 3

I/O

Co

mm

s

8 A

C s

ing

le-p

ha

se in

pu

ts

8 A

C s

ing

le-p

ha

se in

pu

ts

8 A

C s

ing

le-p

ha

se in

pu

ts

Oth

er

UR

-ba

sed

IE

Ds

B90 is built on UR hardware (4 years of field experience)B90 is built on UR hardware (4 years of field experience)

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B90 Components: Logic IEDs

• Modular architecture (from 2 to 9 modules)• All modules but CPU and PS optional• Up to 96 digital inputs or• 48 output contacts or• Virtually any mix of the above• Features oriented towards logic functions (BF

logic and timers, isolator monitoring and alarming)

Po

wer S

up

ply

CP

U

Oth

er

UR

-ba

sed

IE

Ds

I/O

I/O

I/O

I/O

I/O

I/O

Co

mm

s

B90 is built on UR hardware (4 years of field experience)B90 is built on UR hardware (4 years of field experience)

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B90 Scheme for Large Busbars

Dual (redundant) fiber with 3msec delivery time between neighbouring IEDs. Up to 8 B90s/URs in the ring

Phase A AC signals and trip contacts

Phase B AC signals and trip contacts

Phase C AC signals and trip contacts

Digital Inputs for isolator monitoring and BF

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Security of the B90 Communications

• Dual (redundant) ring – each message send simultaneously in both directions

• No switching equipment (direct TX-RX connection)• Self-monitoring incorporated• Information re-sent (repeated) automatically• 32-bit CRC• Default states of exchanged flags upon loss of

communications (allows developing secure applications)

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B90 Communications

• The communications feature (Direct I/Os) requires digital communications card (dual-port 820nmm LED)

• Up to 96 inputs / outputs could be sent / received• Up to 8 UR IEDs could be interfaced• When interfacing with other URs, 32 inputs / outputs

are available• The Direct I/O feature is modeled on UCA GOOSE but

is sent over dedicated fiber (not LAN) and is optimized for speed

• User-friendly configuration mechanism is available• Simple applications do not require communications

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Typical B90 Applications for Large Busbars

7 to 24 feeders

Basic: 87 & BFfor less than 16feeders

Extended: BF for morethan 16 feeders

Full version: 24 Feederswith BF.

1 2 3 23 24

ZONE 1

1 2 3 21 22

ZONE 1

ZONE 2

23 24

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Typical B90 Applications for Large Busbars

7 to 24 feeders

7 to 24 feeders

1

2

3

4

21

22

23

24

ZONE 1

ZONE 2

1 2 11

ZONE 1

12 13 22

23 24 ZONE 2

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B90 and Small Single Busbars – 8-circuit busbar

Two levels of scalability allow flexible applicationsTwo levels of scalability allow flexible applications

Po

wer S

up

ply

CP

U

DS

P 1

I/O

DS

P 2

I/O

DS

P 3

I/O

Sp

are

8 p

ha

se-A

cu

rre

nts

8 p

ha

se-B

cu

rre

nts

8 p

ha

se-C

cu

rre

nts

Diff

Zo

ne

1

Diff

Zo

ne

2

Diff

Zo

ne

3

One B90 IED with 3 zones could protect a single

8-circuit busbar!

One B90 IED with 3 zones could protect a single

8-circuit busbar!

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Po

wer S

up

ply

CP

U

DS

P 1

I/O

DS

P 2

I/O

DS

P 3

I/O

Sp

are

8 p

ha

se-A

cu

rre

nts

4 p

ha

se-A

cu

rre

nts

8 p

ha

se-B

cu

rre

nts Two B90 IEDs with 2 zones

could protect a single 12-circuit busbar!

Two B90 IEDs with 2 zones could protect a single

12-circuit busbar!4

ph

ase

-B c

urr

en

ts

Po

wer S

up

ply

CP

U

DS

P 1

I/O

DS

P 2

I/O

Sp

are

Sp

are

Sp

are

8 p

ha

se-C

cu

rre

nts

4 p

ha

se-C

cu

rre

nts


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Po

wer S

up

ply

CP

U

DS

P 1

I/O

DS

P 2

I/O

Sp

are

Sp

are

Sp

are

8 p

ha

se-A

cu

rre

nts

8 p

ha

se-A

cu

rre

nts

Po

wer S

up

ply

CP

U

DS

P 1

I/O

DS

P 2

I/O

Sp

are

Sp

are

Sp

are

8 p

ha

se-B

cu

rre

nts

8 p

ha

se-B

cu

rre

nts

Po

wer S

up

ply

CP

U

DS

P 1

I/O

DS

P 2

I/O

Sp

are

Sp

are

Sp

are

8 p

ha

se-C

cu

rre

nts

8 p

ha

se-C

cu

rre

nts

Three B90 single-zone IEDscould protect a single 16..24-circuit busbar!

Three B90 single-zone IEDscould protect a single 16..24-circuit busbar!


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Applicability to Ungrounded and Lightly Grounded Systems

• Three phase protection units for phase-to-phase faults and saturation detection

• Fourth unit with AC inputs for zero-sequence differential protection (fed from split-core or regular CTs)

B90 can be applied to solidly and lightly grounded as well as ungrounded systems

B90 can be applied to solidly and lightly grounded as well as ungrounded systems

IA IB IC

3I0

Phase A Phase B Phase C

Ground

Block on external fa

ults

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B90 Configuration Program(1) B90 Protection system is a “site” …

(2) That includes the required IEDs

(3) Functions available for dealing with all IEDs simultaneously

• URPC program used for configuration• Common setting file for all B90 IEDs• All B90 can be accessed

simultaneously• Off-line setting files can easily be

produced

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B90 Algorithms

• Bus differential protection• Dynamic bus replica• Isolator monitoring and alarming• End Fault Protection• Breaker Failure

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diffe

rent

ial

restraining

CT Saturation Problem

External fault: ideal CTs

t0 – fault inceptiont2 – fault conditions

t0

t2

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diffe

rent

ial

restraining


External fault: CT ratio mismatch

t0 – fault inceptiont2 – fault conditions

t0

t2

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diffe

rent

ial

restraining


External fault: CT saturation

t0 – fault inceptiont1 – CT saturation timet2 – CT saturated

t0

t1

t2

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Differential Protection

• B90 algorithms aimed at:– Improving the main differential function by providing

better filtering, faster response, better restraining technique, robust switch-off transient blocking, etc.

– Incorporating a saturation detection mechanism that would recognize CT saturation on external faults in a fast and reliable manner

– Applying a second protection principle namely phase directional (phase comparison) for better security

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Bus Differential Function – Block Diagram

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B90 Differential Function – Theory of Operation

• Definition of the Restraining Current• Operating Characteristic• CT Saturation Detector• Default Tripping Logic• Customizing the Tripping Logic

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“maximum of”

“geometrical average”

“scaled sum of”

“sum of”nR iiiii ...321

nR iiiin

i ...1

321

nR iiiiMaxi ,...,,, 321

nnR iiiii ...321

Various Definitions of the Restraining Signal

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Restraining Current

• The amount of restraint provided by various definitions is different; sometimes significantly different particularly for multi-circuit differential elements such as busbar protection

• When selecting the slope (slopes) one must take into account the applied definition of the restraining signal

• The B90 uses the “maximum of” definition of the restraining current

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“Sum of” vs. “Max of” definitions of restraint

• “Sum of” approach:– more restraint on external faults; less sensitivity on internal

faults– “scaled sum of” may take into account the actual number of

connected circuits increasing sensitivity– characteristic breakpoints difficult to set

• “Max of” approach (B30, B90 and UR in general):– less restraint on external faults– more sensitivity on internal faults– breakpoints easier to set– better handles situations when one CT may saturate

completely (99% slope settings possible)

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Differential Function – Characteristic

diffe

rent

ial

restraining

LOWSLOPE

OPERATE

BLOCK

I R

|I D |

HIGHSLOPE

LOW

BPN

T

HIGH

BPN

T

PICKUP

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Differential Function – Adaptive Approach

diffe

rent

ial

restraining

Region 1(low differential

currents)

Region 2(high differential

currents)

• low currents

• saturation possible due to dc offset

• saturation very difficult to detect

• more security required

• large currents

• quick saturation possible due to large magnitude

• saturation easier to detect

• security required only if saturation detected

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Adaptive Logic

DIF1

DIR

SAT

DIF2

OR

AN

D

OR TRIP

AN

D

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Adaptive Approach

diffe

rent

ial

restraining

Region 1(low differential

currents)

Region 2(high differential

currents)

Dynamic 2-out-of-2,1-out-of-2 operating

mode

2-out-of-2operating

mode

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Directional Principle

DIF1

DIR

SAT

DIF2

OR

AN

D

OR TRIP

AN

D

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• Voltage signal is not required• Internal faults:

– all fault (“large”) currents approximately in phase

• External faults:– one current approximately out of phase

Secondary current ofthe faulted circuit

(deep CT saturation)

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• Implementation:– step 1: select fault “contributors”

• A “contributor”is a circuit carrying significant amount of current• A circuit is a contributor if its current is above higher break

point• A circuit is a contributor if its current is above a certain portion

of the restraining current– step 2: check angle between each contributor and the sum of all

the other currents• Sum of all the other currents is the inverted contributor if the

fault is external; on external faults one obtains an angle of 180 degrees

– step 3: compare the maximum angle to the threshold• A threshold is a factory constant of 90 degrees• An angle shift of more than 90 degrees due to CT saturation is

physically impossible

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External Fault

BLOCK

OPERATE

BLOCK

pD

p

II

Ireal

pD

p

II

Iimag

Ip

ID - I p

External Fault Conditions

OPERATE

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Internal Fault

BLOCK

BLOCK

pD

p

II

Ireal

pD

p

II

Iimag

Ip

ID - I p

Internal Fault Conditions

OPERATE

OPERATE

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Saturation Detector

DIF1

DIR

SAT

DIF2

OR

AN

D

OR TRIP

AN

D

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diffe

rent

ial

restraining

Saturation Detector

t0

t1

t2

t0 fault inceptiont1 CT starts to saturatet2 external fault under

heavy CT saturationconditions

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Saturation Detector – The State Machine

NORMAL

SAT := 0

EXTERNAL

FAULT

SAT := 1

EXTERNALFAULT & CT

SATURATION

SAT := 1

The differentialcharacteristic

entered

The differential-restraining trajectoryout of the differential

characteristic forcertain period of time

saturationcondition

The differentialcurrent below thefirst slope forcertain period oftime

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Saturation Detector

• Operation:– The SAT flag WILL NOT be set during internal faults

whether or not any CTs saturate– The SAT flag WILL be SET during external faults

whether or not any CTs saturate– By design the SAT flag is NOT used to block the

relay but to switch to 2-out-of-2 operating principle

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Examples – External Fault

0.06 0.07 0.08 0.09 0.1 0.11 0.12-200

-150

-100

-50

0

50

100

150

200

time, sec

curr

en

t, A

~1 ms

The bus differentialprotection elementpicks up due to heavyCT saturation

The CT saturation flagis set safely before thepickup flag

Despite heavy CTsaturation theexternal fault currentis seen in theopposite direction

Thedirectional flagis not set

The elementdoes notmaloperate

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Examples – Internal Fault

The bus differentialprotection elementpicks up

The saturationflag is not set - nodirectionaldecision required

The elementoperates in10ms

All the fault currentsare seen in one

direction

Thedirectionalflag is set

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User-Modified Tripping Logic

• All the key logic flags (DIFferential, SATuration, DIRectional) are available as FlexLogicTM operands with the following meanings:

• BUS BIASED PKP - differential characteristic entered• BUS SAT - saturation (external fault)

detected• BUS DIR - directionality confirmed (internal

fault)• FlexLogicTM can be used to override the default 87B logic• Example: 2-out-of-2 operating principle with extra security applied

to the differential principle:

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Dynamic Bus Replica

• Dynamic bus replica mechanism is provided by associating a status signal with each current of a given differential zone

• Each current can be inverted prior to configuring into a zone (tie-breaker with a single CT)

• The status signal is a FlexLogicTM operand (totally user programmable)

• The status signals are formed in FlexLogicTM – including any filtering or extra security checks – from the positions of switches and/or breakers as required

• Bus replica applications:– Isolators– Tie-Breakers– Breakers

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Dynamic Bus Replica - Isolators

• Reliable “Isolator Closed” signal is composed• The Isolator Position signal:

– Decides whether the associated current is to be included into differential calculations

– Decides whether the associated breaker is to be tripped• For maximum safety:

– Both normally open and normally closed contacts are used– Isolator alarm is established under discrepancy conditions– Isolator position to be sorted out under non-valid combinations

of the auxiliary contacts (open-open, closed-closed)– Switching operations in the substation shall be inhibited until

the bus image is recognized with 100% accuracy– Optionally the 87B may be inhibited from the isolator alarm

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Dynamic Bus Replica - Isolators

Isolator Open Auxiliary Contact

Isolator Closed Auxiliary Contact

Isolator Position

Alarm Block Switching

Off On CLOSED No No

Off Off LAST VALID After time delay until acknowledged

Until Isolator Position is valid

On On CLOSED

On Off OPEN No No

ISOLATOR 1 OPEN

ISOLATOR 1 CLOSED

ISOLATOR 1 BLOCK

ISOLATOR 1 ALARM

ISOLATOR 1 RESET

ISOLATOR 1 POSITION

Isolator position valid(isolator opened)

Isolator position valid(isolator opened)

Isolator position invalid

alarm timedelay

blocking signal resets whenisolator position valid

alarmacknowledged

alarm acknowledgingsignal

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Dynamic Bus Replica – Isolator Positions and Differential Protection

Phase A AC signals wired here, bus replica configured here

Phase B AC signals wired here, bus replica configured here

Phase C AC signals wired here, bus replica configured

here

Up to 96 auxuliary switches wired here; Isolator Monitoring function configured here

Isolator P

osition

Isolator Position

Isolator Position

Isolator Positio

n

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Dynamic Bus Replica – Tie-Breakers: Two-CT Configuration

• Overlapping zones – no blind spots• Both zones trip the Tie-Breaker• No special treatment of the TB required in terms of its

status for Dynamic Bus Replica (treat as regular breaker – see next section)

TBZ1 Z2

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Dynamic Bus Replica – Tie-Breakers Tie-Breakers: Single-CT Configuration

• Both zones trip the Tie-Breaker• Blind spot between the TB and the CT• Fault between TB and CT is external to Z2• Z1: no special treatment of the TB required (treat as

regular CB)• Z2: special treatment of the TB status required:

– The CT must be excluded from calculations after the TB is opened

– Z2 gets extended (opened entirely) onto the TB

TBZ1 Z2

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Tie-Breakers: Single-CT Configuration

• Sequence of events:– Z1 trips and the TB gets opened– After a time delay the current from the CT shall be

removed from Z2 calculations– As a result Z2 gets extended up to the opened TB– The Fault becomes internal for Z2– Z2 trips finally clearing the fault

expand

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Dynamic Bus Replica – Breakers: Bus-side CTs

• Blind spot exists between the CB and CT• CB is going to be tripped by line protection• After the CB gets opened, the current shall be removed from

differential calculations (expanding the differential zone up to the opened CB)

• Relay configuration required: identical as for the Single-CT Tie-Breaker

CT

CB

Blind spot forbus protection

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Dynamic Bus Replica –Breakers: Line-side CTs

• “Over-trip” spot between the CB and CT when the CB is opened• When the CB gets opened, the current shall be removed from

differential calculations (contracting the differential zone up to the opened CB)

• Relay configuration required: identical as for a Single-CT Tie-Breaker, but….

CB

CT

“Over-trip” spot forbus protection

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Dynamic Bus Replica –Breakers: Line-side CTs

• but….• A blind spot created by contracting the bus differential zone• End Fault Protection required – B90 provides one EFP element per

current input

CB

CT

Blind spot forbus protectioncon

tract

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End Fault Protection

SETTING

EFP 1 FUNCTION:

Disabled = 0

Enabled = 1

SETTING

EFP 1 CT:

Current Magnitude, |I|

FLEXLOGIC OPERANDS

EFP 1 OP

SETTING

B90 FUNCTION:

Logic = 0

Protection = 1

AN

D

SETTING

EFP 1 BLOCK:

Off = 0

EFP 1 DPO

EFP PKP

SETTINGS

EFP 1 BRK DELAY:

tPKP

0

SETTING

| I | > PICKUP

RUN

EFP 1 PICKUP:

SETTING

EFP 1 MANUAL CLOSE:

Off = 0

SETTING

EFP 1 BREAKER OPEN:

Off = 0

AN

D

SETTING

EFP 1 PICKUP DELAY:

tPKP

0

(1) The EFP gets armed after the breaker is open

(2) Excessive current ….

(3) Causes the EFP to operate

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Breaker Failure Protection

• BF Architecture:– Current supervision residing on “protection” IEDs– BFI signal can be generated internally (from protection IEDs)

or externally via communications or a digital input from any IED

– BF logic and timers residing on the “logic” IED– Trip contacts distributed freely between various IEDs

• BF Performance:– Reset time of current sensors below 0.7 power system cycle– Communications delays around 0.2 power system cycle

between any two neighboring IEDs

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Breaker Failure Protection – Current Supervision

Phase A AC signals wired here, current status monitored here

Phase B AC signals wired here, current status monitored here

Phase C AC signals wired here, current status

monitored here

Up to 24 BF elements configured here

Current S

tatus

Current Status

Current Status

Current Status

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Breaker Failure Protection – Initiate




monitored here

Up to 24 BF elements configured here

BF Initia

te

BF Initiate

BF Initiate

BF Initiate

BFI

BFI

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Breaker Failure Protection – Trip Action




monitored here

Trip command generated here and send to trip appropraite breakers

Trip C

ommand

Trip Command

Trip Command

Trip Command

Trip

Trip

TripTrip

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Programmable Logic (FlexLogicTM)

• All B90 IEDs provide for programmable logic• Distributed logic over fiber-optic communications

(Direct I/Os)• Functions available:

– Gates– Edge detectors – Latches and non-volatile latches– Timers

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Disturbance Recording

• All AC inputs automatically recorded• Programmable sampling rate: 8, 16, 32, 64 s/c• Programmable content (phasor magnitudes and angles,

differential, restraint currents, frequency, any digital flag)• Programmable number of records vs. record length• Flexible treatment of old records (overwrite, preserve)• Programmable trigger• Programmable pre-/post-trigger windows• Individual (independent) oscillography configuration of each B90

IED

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Sequence of Events Recording

• Up to 1040 events per each B90 IED• Events stamped with 1microsecond resolution• 0.5 msec scanning rate for digital inputs• All B90 IEDs synchronized via IRIG-B or SNTP• All events (except hardware-related alarms) user programmable• Events can be enabled independently for:

– All protection elements – All digital inputs and contact outputs– Communications driven signals

• Individual (independent) SOE configuration of each B90 IED

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Substation one-line andwiring diagrams

F4-Z2-INVO 23

F3-Z2-INVO 22

F2-Z2-INVO 21

F4-Z1-INVO 7

SWITCHING ON Z1 & Z2, Z1 & Z3 OR Z2 & Z3 BUSBARS

B

F3-Z1-INVO 6

F2-Z1-INVO 5

F1-Z1-IN& Z2-OUTVO 4

ISO 1

TRIP PERM Z1/Z2 VO 63

600

ISO 3

LATCH

ISO 6

ISO 9

0100

CLOSING ORDER

52b

F2-Z1-OUTVO 53

F2-Z2-OUTVO 54

B

A

AISO 3

A

ISO 1ISO 2

ISO 4

ISO 7

ISO 2

ISO 5

ISO 8

F2-Z3-INVO 37

F3-Z3-INVO 38

F4-Z3-INVO 39

OPTION: ZONE 3 ASTRANSFER BUS

LOGIC FOR COUPLER

ISO 2

ISO 3

ISO 1

ISO 3

ISO 2

ISO 6

ISO 5

ISO 9

ISO 8

ISO 6

ISO 4

ISO 9

ISO 7

ISO 5

ISO 4

ISO 8

ISO 7

Logic design FlexLogicTM Implementation

Engineering the B90

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B90 Summary

• Cost-efficient• Good performance• Modern communications capability• Member of the Universal Relay (UR) family• Easy integration with other URs• Common configuration tool for all B90 IEDs• Proven algorithms (B30) and hardware (UR) • Expandable• Two levels of scalability (modules and IEDs)

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Ordering the B90

• The B90 can be ordered as an engineered product• The following order code applies to the engineered B90

B90 * * * * ** * * **

B90 Base system

S Single busbar

D Double busbar

T Double busbar with transfer

X Special arrangement

C Cabinet supply

F Frame supply

A RS485 + RS485 (ModBus RTU, DNP)

C RS485 + 10BaseF (MMS/UCA2, ModBus TCP/IP, DNP)

D RS485 + redundant 10BaseF (MMS/UCA2, ModBus, TCP/IP, DNP)

H 125/250, AC/DC

L 24-48V (DC only)

** Specify the number of lines + bus couplers (two digits)

0 Without Breaker Fail

B With Breaker Fail

0 Without End Fault Protection

E With End Fault Protection

00 Sequential number

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How to Order

• International: +1 905 294 6222• Europe: +34 94 485 88 00• Email: [email protected]• Web:

http://www.GEindustrial.com/pm

B90 Bus Differential Relay and Breaker Failure Protection

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