GE GEK 106168E User Manual

GE Power Management

Digital Breaker Failure Protection

Digital Breaker Failure ProtectionDigital Breaker Failure Protection

DBF

Instructions

InstructionsInstructions GEK 106168E

GEK 106168E

GEK 106168E GEK 106168E

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TABLE OF CONTENTS

TABLE OF CONTENTSTABLE OF CONTENTS

1. GENERAL DESCRIPTION AND APPLICATION........................................................................................... 1

1.1. GENERAL DESCRIPTION................................................................................................................................. 1

2. OPERATION LOGIC...................................................................................................................................... 3

2.1. PROTECTION FUNCTIONS.............................................................................................................................. 3

2.1.1. Overcurrent units.......................................................................................................................................... 3

2.2. MONITORING AND RECORDING FUNCTIONS.............................................................................................. 5

2.2.1 Measurement............................................................................................................................................... 5

2.2.2 Associated Breaker Status........................................................................................................................... 5

2.2.3 Target Lamps ............................................................................................................................................... 5

2.2.4 Circuit Breaker Breaking Capacity Monitoring ............................................................................................. 9

2.2.5 Built-in Self-Checking Unit.......................................................................................................................... 10

2.3. ANALYSIS FUNCTIONS......................................................................................................................................... 10

2.3.1 Event Recorder........................................................................................................................................... 10

2.3.1 Oscillography .............................................................................................................................................. 10

2.4. CONTROL.......................................................................................................................................................... 12

2.4.1 Tables of Settings ...................................................................................................................................... 12

2.4.2 Time Synchronization.................................................................................................................................. 13

2.4.3 Configurable Inputs and Outputs ............................................................................................................... 13

2.5. MAN-MACHINE INTERFACE (HMI)........................................................................................................................ 15

EMOTE COMMUNICATIONS................................................................................................................................16

2.6. R

3. SETTINGS.................................................................................................................................................... 17

4. TECHNICAL CHARACTERISTICS.............................................................................................................. 21

4.1. M

4.2. TECHNICAL CHARACTERISTICS ............................................................................................................................ 22

5. HARDWARE DESCRIPTION....................................................................................................................... 25

5.1. P

5.2. OPERATING THEORY.......................................................................................................................................... 27

6. ACCEPTANCE TESTS................................................................................................................................. 29

6.1. C

6.2. V

6.3. P

6.4. R

6.5. I

6.6. P

6.7. C

6.8. I

6.9. FUNCTIONS......................................................................................................................................................... 33

ODEL LIST....................................................................................................................................................... 21

4.1.1. Special Models........................................................................................................................................... 21

HYSICAL DESCRIPTION..................................................................................................................................... 25

5.1.1. Case.......................................................................................................................................................... 25

5.1.2. Electrical Connections............................................................................................................................... 25

5.1.3. Internal Construction................................................................................................................................. 25

5.2.1. Magnetic Module....................................................................................................................................... 27

5.2.2. CPU Board................................................................................................................................................ 27

5.2.3 Power Supply ............................................................................................................................................. 28

5.2.4 Keyboard and Display................................................................................................................................ 28

ONNECTIONS AND NECESSARY EQUIPMENT...................................................................................................... 29

ISUAL INSPECTION ........................................................................................................................................... 29

ANEL INSULATION TESTS.................................................................................................................................. 29

ELAY SETTING................................................................................................................................................. 30

NDICATORS........................................................................................................................................................ 30

OWER SUPPLY................................................................................................................................................. 30

OMMUNICATIONS .............................................................................................................................................. 31

NPUTS............................................................................................................................................................... 32

6.8.1 Digital inputs................................................................................................................................................ 32

6.8.2 IRIG-B Synchronizing Input........................................................................................................................ 32

6.9.1 50BF 1P Unit Test...................................................................................................................................... 33

6.9.2 50BF 3P Unit Test...................................................................................................................................... 34

6.9.3 Internal Arc Test......................................................................................................................................... 35

6.9.4 3P NO I FUNCTION.................................................................................................................................... 35

GEK-106168E DBF Breaker Failure Protection i

TABLE OF CONTENTS

6.9.5 Neutral Overcurrent Unit Test.....................................................................................................................35

6.10. RELAY MEASUREMENT TESTS ...........................................................................................................................37

6.10.1. Current Measurement..............................................................................................................................37

6.10.2. Timing Measurement...............................................................................................................................37

7. INSTALLATION AND MAINTENANCE........................................................................................................39

7.1. I

NSTALLATION.....................................................................................................................................................39

ONNECTION-TO-GROUND AND DISTURBANCES SUPPRESSION............................................................................39

7.2. C

7.3. M

AINTENANCE....................................................................................................................................................39

8. KEYBOARD AND DISPLAY........................................................................................................................41

8.1. M

8.2. S

8.3. I

8.4. C

8.5. S

8.6. C

ENU TREE. ......................................................................................................................................................42

ETTINGS GROUP (SET KEY) ..............................................................................................................................43

NFORMATION GROUP (INF KEY)..........................................................................................................................46

ONTROL GROUP (ACT KEY) .............................................................................................................................47

INGLE KEY MENU .............................................................................................................................................48

ONFIGURATION MENU.......................................................................................................................................49

FIGURES .................................................................................................................................................................51

ii DBF Breaker Failure Protection GEK-106168E

LIST OF FIGURES

Figure 1. Breaker Failure Logic (189C4114 Sheet 2) Figure 2. External Connections (189C4114 Sheet 1) Figure 3. Front View (226B7412 Sheet 9) Figure 4. Rear View (226B7412 Sheet 10) Figure 5. Dimensions Diagram (226B6086 sheet 10) Figure 6. Panel drilling (226B6086H10) Figure 7. RS232 Connection (DBF relay to PC) Figure 8. RS232 Connection (DBF relay to MODEM)

GEK-106168E DBF Breaker Failure Protection iii

LIST OF FIGURES

iv DBF Breaker Failure Protection GEK-106168E

1. GENERAL DESCRIPTION AND APPLICATION

1. 1.

GENERAL DESCRIPTION AND APPLICATION

GENERAL DESCRIPTION AND APPLICATIONGENERAL DESCRIPTION AND APPLICATION

1.1. GENERAL DESCRIPTION

The DBF system is a microprocessor based breaker failure protection, control and measurement unit that has different algorithms to allow its use on a wide range of applications in power systems.

The functions and information management of the unit can be performed remotely (computer connected to the serial port RS232, fiber-optic or modem) or locally using the man-machine interface (HMI), which includes a 20 keys keypad, and a two line liquid crystal display (LCD) on the front of the relay.

The system provides the following functions:

a) Protection

• Low current level breaker failure protection, following a single or three phases initiation, with up to two time delayed steps.

• High current level breaker failure protection, following a two/three (selectable by setting) phases initiation.

• No current breaker failure protection, following a two/three (selectable by setting) phases initiation.

• Breaker internal arc detection.

b) Monitoring

• Current measurements for each phase and ground.

• Breaker status

• 16 fully configurable LED indicators

• One fixed relay status LED

• Breaker health monitoring (ΣI2t).

• Built-in self-check functions.

c) Analysis:

• Event recorder

• Oscillography

d) Control:

• 3 settings’ tables

• Time synchronization using the communications program, the IRIG-B input or the HMI (keypad and

display).

• Configurable inputs and outputs.

• User can build logic schemes using AND, OR and NOT gates and the internal digital signals of the

relay.

GEK-106168E DBF Breaker Failure Protection 1

1. GENERAL DESCRIPTION AND APPLICATION

e) Communication Interfaces

• Remote communications through three communication ports, one on the front of the relay and two located on the rear.

• Human machine interface (HMI) consisting of 20 keys keypad and alphanumerical LCD (16 characters x 2 lines).

• Windows based GE-INTRO configuration software (for inputs, outputs, LEDs configuration) and GE-LOCAL communications software (for relay monitoring, settings change, stored data retrieve, etc). Both are part of the GE-NESIS software package (General Electric Network Substation Integrated System).

2 DBF Breaker Failure Protection GEK-106168E

2. OPERATION LOGIC

2. OPERATION

2. 2.

(See f igur e 1 at the end of the Ins truc tion Manual)

OPERATION LOGIC

OPERATION OPERATION

LOGIC

LOGICLOGIC

2.1. PROTECTION FUNCTIONS

2.1.1. OVERCURRENT UNIT S

The DBF system incorporates the following overcurrent detectors:

• Three Single Phase Low-Level Overcur rent Detector s

(Used by the 50BF 1P function.)

• Three Single Phase High- Level Overcur rent Detector s.

(Used by the 50BF 3P function.)

• One G r ound Overcur rent Detector .

(Used by the 3P No I function.)

• Three Single-Phase current detectors for the internal arc function.

Low-Level Overcurrent Breaker Failure Unit – 50BF 1P The breaker failure operation is star ted by detecting any single phase above a setpoint threshold (PH Lo-Set

Pickup setting), ANDed with a tripping signal (break er failure initiate signal) issued by the main feeder protection.

These breaker f ailure initiation signals can be s ingle-phas e or three-phase type at OR1, OR2 and OR3. There are four digital signals available (50BF Initiate A, 50BF Initiate B any digital input (contact converter). The factory digital input conf igur ation is the following (as shown in f igur e 1):

Digital Signal Input # Terminals

50BF Initiate A Input #1 C9 – D10 50BF Initiate B Input #2 D9 – D10 50BF Initiate C Input #3 C10 – D10

3P BF Initiate Input #7 E7 – E8

The AND1, AND2 and AND3 gates thus fully armed m ay perform (depending on settings) one or two time delayed tripping steps. Use 50BF_1P setting ( permitted/Not permitted) and number of output stages (N. of Output Stages) setting to enable this f unc tion and to set the number of steps. Timers T1 and T2nd control t he timing of the f ir s t and second step respec tively (1_Phase T imer T 1 and 2nd Stage Timer settings).

If the tr ipping signal is three-pole type (digital input E7-E8 for the default factor y configuration), the s ignal will be placed at the same time in OR1, OR2 and OR3 and then to AND1, AND2 and AND3.

High-Level Overcurrent Breaker Failure Unit – 50BF 3P

, 50BF Initiate C and 3P BF Initiate) assignable to

This func tion operates if high-Level overc urr ent is detected on 2 phases (or 3 phases if se tting BF Logic (3P/2P) is set to 3P) and if 2 break er failure initiation inputs are energized (or j us t the 3P BF Initiate input, if Severe Fault 3P setting is set to permitted) .

The starting of this function is similar to the 50BF 1P, but in this case the current level setting range is higher (PH Hi-Set Pickup s etting) and the output is controlled by the energization of two single pole initiation signals. This function can also operate ener gizing the 3P BF Initiate signal, if Severe Fault 3P setting is set to ‘permitted’.

Other diff er enc e with res pect to the 50BF 1P f unc tion, is that the current in all the three phases must exceed the setpoint, or at least one pair of phases. This is selected with BF Logic (3P/2P) setting. In the first case (BF Logic (3P/2P) s et to 3P) the signal should progress through AND11 and AND12. If BF Logic (3P/2P) issetto2P,then the signal will go through AND8, AND9 or AND10 and then AND13. The outputs of AND12 or AND13 ar e sent via

GEK-106168E DBF Breaker Failure Protection 3

2. OPERATION LOGIC

OR5 to the bottom input of AND4. Any pair of single BF initiation signals placed at AND5, AND6,orAND7 will activate the top input of AND4. This input to AND4 can also be ON if there is a 3P BF Initiation and Severe Fault 3P setting is set to ‘permitted’.

Ground Overcurrent Breaker Failure Unit.

The breaker failure action based in this ground overcurrent function basically performs an additional breaker failure function through AND19, when the 3P BF Initiate (or 2 Single Pole BF Initiate, if Low Load 2P set to ‘permitted’) is present at OR10 and a ground current higher than Neutral Pickup setting is detected.

Breaker Failure without current (or very low current).

DBF includes internal logic to cover also no-current, or very low fault current BF applications. This function will issue an output if the 3P BF Initiate input is energized (or 2 Single Pole BF Initiate, if Low Load 2P to ‘permitted’), and at least one pole of the circuit breaker is still closed.

Breaker Arc Detection Device.

This function may close one output of the relay when it detects that: the circuit breaker is open and some amount of current is present in any phase. There are two settings available for this function: ‘Internal Arc Pickup’toset the current threshold and ‘Internal Arc Timer’ to coordinate the operation time of the unit with the time it takes for the breaker and auxiliary elements to open.

setting is

setting is set

If the circuit breaker is open, then the 52/b contacts will energize the digital inputs corresponding to the circuit breaker status (terminals C11-D12, D11-D12 and C12-D12 for the factory default configuration), and then the upper input of AND16, AND17 and AND18. The other input will be energized if the DBF detects a current higher than Internal Arc Pickup setting. The outputs of these AND gates are sent to OR8 and then to timer T4 (Internal Arc Timer setting) to complete the arc detection function, this will close the auxiliary relay D2-C2 (according to the factory default output configuration).

Reset of Latching Relays

The DBF breaker failure protection may be ordered with an expansion board, which includes two latching relays that are operated in different ways depending on the number of steps selected (for additional reference see Figure

1), and will fix the tripping output once the breaker failure function has operated. A digital input through F11-F12 (factory default inputs configuration) (pulse signal, not sustained) resets these latching relays to its steady-state position.

4 DBF Breaker Failure Protection GEK-106168E

2. OPERATION LOGIC

2.2. MONITORING AND RECORDING FUNCTIONS

2.2.1 MEASUREMENT

The DBF system provides the continuous measurement of phase and ground current values. These measurements can be accessed directly on the liquid crystal display (HMI) on the front of the relay, or via

the GE-LOCAL communication software.

2.2.2 ASSOCIATED BREAKER STATUS

The DBF system monitors the associated breaker status through the digital inputs 52/b (or 52/a), and it is displayed on the local HMI or through the communications software.

2.2.3 TARGET LAMPS

The DBF incorporates 17 LED target lamps, one fixed LED (two colors) assigned to the system ready function, and 16 user configurable red LEDs. These configurable LEDs are arranged in two columns of 8 LEDs each. The configuration is done using the GE-INTRO software, and it consists on assigning an internal event (or an AND gate of internal events) to an LED. The LED can be configured to have memory (if Vdc is removed or the event causing the operation of the LED gets deactivated) or not and to blink or to be steady. The internal events must be previously defined using the internal signals of the relay. It is possible to use AND, OR and NOT logic gates to define these events. The available internal signals are listed in the following table.

The TARGET RESET button allows testing all target lamps if it is pushed for a short time (lighting up all of them), or resets the sealed-in targets if it remains pressed for three seconds or more.

Please refer to GE_INTRO (configuration software) Instruction book (GEK-105594) for further information.

INTERNAL PROTECTION STATUS SIGNALS

Group Status Comment

1.0 Program Initiate Relay starts running (Vdc just applied).

1.1 Settings change User changes any setting

1.2 Write Counters User sets a value for any counter

1.3 Configuration Change User changes relay configuration

1.4 External Trigger Oscillography triggered by Dig. Input

1.5 Communications Trigger Osc. triggered by HMI or GE_LOCAL

1.6 Reset Operation Latched Relays Reset received

1.7

1.8

1.9

1.10

1.11

1.12

1.13

1.14

1.15

2.0 Input Nº 1 Digital Input #1 Status

2.1 Input Nº 2 Digital Input #2 Status

2.2 Input Nº 3 Digital Input #3 Status

2.3 Input Nº 4 Digital Input #4 Status

2.4 Input Nº 5 Digital Input #5 Status

2.5 Input Nº 6 Digital Input #6 Status

2.6

GEK-106168E DBF Breaker Failure Protection 5

2. OPERATION LOGIC

Group Status Comment

2.7 Optional Exp. Board

2.8 Input Nº 7 Digital Input #7 Status

2.9 Input Nº 8 Digital Input #8 Status

2.10 Input Nº 9 Digital Input #9 Status

2.11 Input Nº 10 Digital Input #10 Status

2.12 Input Nº 11 Digital Input #11 Status

2.13 Input Nº 12 Digital Input #12 Status

2.14 Input Nº 13 Digital Input #13 Status

2.15 Input Nº 14 Digital Input #14 Status

3.0 Breaker Failure Logic BF Logic = 3P

3.1 Hi-Set A Pickup Output of Hi-Set current detector ph A

3.2 Hi-Set B Pickup Output of Hi-Set current detector ph B

3.3 Hi-Set C Pickup Output of Hi-Set current detector ph C

3.4 50BF Pole A Initiate CC1 Dig. Input ON (default configuration)

3.5 50BF Pole B Initiate CC2 Dig. Input ON (default configuration)

3.6 50BF Pole C Initiate CC3 Dig. Input ON (default configuration)

3.7 Lo-Set A Pickup Output of Lo-Set current detector ph A

3.8 Lo-Set B Pickup Output of Lo-Set current detector ph B 3-9 Lo-Set C Pickup Output of Lo-Set current detector ph C

3.10 50BF 3 Phase Initiate CC7 Dig. Input ON (default configuration)

3.11 50BF Neutral Initiate Output of Neutral current detector

3.12 Internal Arc A Pickup Output of AND 16 in figure 1

3.13 Internal Arc B Pickup Output of AND 17 in figure 1

3.14 Internal Arc C Pickup Output of AND 18 in figure 1

3.15

4.0 Pickup

4.1 Trip 1

4.2 Trip 2

4.3 Internal Arc

4.4

4.5

4.6

4.7

4.8

4.9

4.10

4.11

4.12

4.13

4.14

4.15

5.0 Phase A Trip Output of Timer 1 phase A in figure 1

5.1 Phase B Trip Output of Timer 1 phase B in figure 1

5.2 Phase C Trip Output of Timer 1 phase C in figure 1

5.3 Three-Pole Trip with Current Output of Timer 2 in figure 1

5.4 Three-Pole Trip without Current Output of Timer 3 in figure 1

5.5 Second Stage Trip Output of AND 14 / 15 in figure 1

5.6

5.7

5.8

Any BF signal is activated. Output of OR 7infigure1 Any unit (except Internal Arc) has tripped. Output of OR 6 in figure 1 Same as Trip 1 when 1 step is selected. 2ndstage when 2 steps are selected. Output of AND 14 / 15 in figure 1 Trip from Internal Arc unit. Output of Timer 4 in figure 1

6 DBF Breaker Failure Protection GEK-106168E

2. OPERATION LOGIC

Group Status Comment

5.9

5.10

5.11

5.12

5.13

5.14

5.15

6.0

6.1 Parallel EEPROM Alarm Failure in parallel EEPROM

6.2 Serial EEPROM Alarm Failure in serial EEPROM

6.3 Out-of-Service Relay out of service

6.4 Default General Settings Relay with factory default settings

6.5 Default Table 1 Settings Table 1 with factory default settings

6.6 Default Table 2 Settings Table 2 with factory default settings

6.7 Default Table 3 Settings Table 3 with factory default settings

6.8

6.9

6.10

6.11 52 A Maintenance Alarm Accumulated I2t above limit for Phase A

6.12 52 B Maintenance Alarm Accumulated I2t above limit for Phase B

6.13 52 C Maintenance Alarm Accumulated I2t above limit for Phase C

6.14

6.15

7.0

7.1 Active Table 1 Setting Table #1 is the active Table

7.2 Active Table 2 Setting Table #2 is the active Table

7.3 Active Table 3 Setting Table #3 is the active Table

7.4

7.5

7.6 New Events There are new events stored in the DBF

7.7 Two Stages Set BF Logic set to 2 timed stages

7.8 Breaker Pole A Status CB Pole A Closed

7.9 Breaker Pole B Status CB Pole B Closed

7.10 Breaker Pole C Status CB Pole C Closed

7.11 Latching Relay 1 Status Optional Exp. Board: Latched#1

Closed

7.12 Latching Relay 2 Status Optional Exp.Boar: Latched#2 Closed

7.13

7.14

7.15

8.0

8.1

8.2

8.3

8.4

8.5

8.6

8.7

8.8

GEK-106168E DBF Breaker Failure Protection 7

2. OPERATION LOGIC

Group Status Comment

8.9

8.10

8.11

8.12

8.13 8,14

8.15

9.0

9.1

9.2

9.3

9.4

9.5

9.6

9.7

9.8

9.9

9.10

9.11

9.12

9.13

9.14

9.15

10.0 AND1 Output of internal AND gate #1

10.1 AND2 Output of internal AND gate #2

10.2 AND3 Output of internal AND gate #3

10.3 AND4 Output of internal AND gate #4

10.4 AND5 Output of internal AND gate #5

10.5 AND6 Output of internal AND gate #6

10.6 AND7 Output of internal AND gate #7

10.7 AND8 Output of internal AND gate #8

10.8 AND9 Output of internal AND gate #9

10.9 AND10 Output of internal AND gate #10

10.10 AND11 Output of internal AND gate #11

10.11 AND12 Output of internal AND gate #12

10.12 AND13 Output of internal AND gate #13

10.13 AND14 Output of internal AND gate #14

10.14 AND15 Output of internal AND gate #15

10.15 AND16 Output of internal AND gate #16

INTERNAL COMMUNICATION STATUS SIGNALS

Group Status Comment

1.0 Remote/Local Mode Relay in remote mode

1.1 Rear Connection Rear communication port in use

1.2 Front Connection Front communication port in use

2.0 Date/Time alarm Synch. Signal not received in setting t Timeout

2.1 Serial EEPROM Alarm Failure in serial EEPROM

2.2 Comm. Settings Relay with factory default settings

2.3 Protection Link Status of internal comm. with protection CPU

2.4 IRIG_B Link Relay synchronized by IRIG_B

3.0 - 3.15

8 DBF Breaker Failure Protection GEK-106168E

Group Status Comment

4.0 - 4.15

5.0 -5.15

The DBF units are supplied with the following target LED’s default configuration:

2. OPERATION LOGIC

LED

LEFT COLUMN LED

RIGHT COLUMN

1 TRIP STAGE 1 9 LOW SET PICKUP 2 TRIPSTAGE2 10 50BFPOLEAINIT 3 PHASEATRIP 11 50BFPOLEBINIT 4 PHASEBTRIP 12 50BFPOLECINIT 5 PHASE C TRIP 13 INT. ARC A POLE 6 3PTRIPNOI 14 INT.ARCBPOLE 7 INT. ARC TRIP 15 INT. ARC C POLE 8 HIGH SET PICKUP 16 REMOTE COMMUNICATIONS

2.2.4 CIRCUIT BREAKER BREAKING CAPACITY MONITORING

To supervise the breaker health, the DBF system calculates and stores, for each operation, the accumulated values of the square of the current multiplied by the opening time of the breaker (I expressed in kA

The value I

sec.

t is accumulated and stored independently for each phase. These values can be accessed either by

t) on each phase. I2tis

the local HMI or by the GE-LOCAL communications software. The function has an

Integration Time Selector

setting (kI2tOPMODE)whichcanbeusedtoassignafixed opening time (given by another setting (kI2tINTTIME)). Otherwise the unit measures the time between the tripping signal of the main feeder protection and the change of the status contacts of the circuit breaker (52/b).

The total

Breaking Current Limit

(kI2t LIMIT) setting fixes the maximum life breaking capability (it is recommended to set this to the limit supplied by the manufacturer). When this threshold is reached in any phase, the system may be configured to close an output, if the appropriate internal signal (52 A Maintenance Alarm, 52 B Maintenance Alarm, 52 C Maintenance Alarm) is assigned to an output. In addition, the system also has a counter for the tripping operations.

The purpose of these functions is to provide accurate data to perform the circuit breaker maintenance, based on the actual breaking time and current values. Once this maintenance operation has been done, the values for both

t and number of opening operations, can be reset.

the I In order to be able to take into account the history of the breaker, in the case where the breakers were already in

use before the installation of the relay, the system allows to set an initial value for the I

t and the number of the previous breaking operations. Similarly, these values can be adjusted to a given value in order to take into account operations carried out during protection testing.

GEK-106168E DBF Breaker Failure Protection 9

2. OPERATION LOGIC

2.2.5 BUILT-IN SELF-CHECKING UNIT

The digital technology of the DBF system allows providing a built-in self-checking function which guarantees the correct performance of the unit, and provides an external alarm in case of error detection.

Two built-in self-checking functions are performed, one when the unit is started up and the other during normal operation. Internal tests are provided for power supply, program memory (ROM), working memory (RAM), oscillography memory (RAM), and settings and calibration memory (EEPROM).

In addition, there is a hardware test for the Target LEDs, which lights them all up when the button TARGET RESET is pressed. The sealed-in targets (latched) reset if the TARGET RESET button is kept pressed during three seconds.

2.3. ANALYSIS FUNCTIONS.

The DBF system includes an event recorder and an oscillography waveform recorder with a resolution of 1 ms for the first one, and 1 sample for the second one (1.04 ms at 60 Hz and 1.25 ms at 50 Hz). To avoid the loss of date/time and oscillography records during any Vdc power failure, the unit is equipped with a capacitor, which allows the information to be kept for at least 24 hours after power loss.

2.3.1 EVENT RECORDER.

The DBF system keeps a record of the last 144 events and stores for each one the following information: date and time (accurate to one millisecond), the type of event, current RMS values during the event, and the state of the unit (set of digital signals that describes the status of the relay at any given moment in time).

This event recorder is stored in a non-volatile memory and can be maintained indefinitely, even with no power supply.

The list of events that the relay stores are factory fixed, and corresponds to standard relevant situations/operations, like Settings Change, Program initiate, Active Table 1, Opening 52 phase C, Closing

52 phase C, Digital Input 1 Activated, etc.

2.3.1 OSCILLOGRAPHY

The DBF unit stores up to 4 oscillography records, with a resolution of 16 samples per cycle. Each record has a maximum capacity of 66 cycles. The number of pre-fault cycles can be selected from 2 to 10 cycles. Each record includes the following information:

• Date and time.

• Name of the signal that triggered the oscillography.

• Active settings table when recording

• Digital information (Status of internal digital signals)

• Instantaneous rms values of currents (I

A,IB,IC

and IN)

A configurable

mask

is available for selecting which functions or internal signals are able to trigger the oscillography. It can either be triggered by a configurable digital input, by a command received from the communication program (GE_LOCAL), or directly from the HMI.

10 DBF Breaker Failure Protection GEK-106168E

The user can select from the following list which signals may trigger the oscillography:

Events to Trigger the

Oscillography

PICKUP 1ST STAGE TRIP 2ND STAGE TRIP INTERNAL ARC 50BF A TRIP 50BF B TRIP 50BF C TRIP 50BF 3P TRIP EXTERNAL TRIGGER COMM. TRIGGER HI-SET A PICKUP HI-SET B PICKUP HI-SET C PICKUP 50BF A INIT 50BF B INIT 50BF C INIT LO-SET A PICKUP LO-SET B PICKUP LO-SET C PICKUP 3 POLE 50BF INIT NEUTRAL PICKUP ARC A PICKUP ARC B PICKUP ARC C PICKUP

2. OPERATION LOGIC

The oscillography records are retrieved from the relay to the computer in COMTRADE international standard format using the GE_LOCAL communications program. To draw the waveforms, digital flags, phasors and postfault analysis in general, it is suggested to use the GE_OSC oscillography program or any other that accepts COMTRADE international format (IEEE-C37.111-1991). It is also possible to import the waveforms with mathematical or spreadsheet programs (for example EXCEL

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2. OPERATION LOGIC

2.4. CONTROL

2.4.1 TABLES OF SETTINGS

The DBF system has two types of settings stored in non-volatile memory (information is kept even when there is no auxiliary voltage):

• Generic Settings.

• Specific Settings.

The

Generic

settings are grouped as follows:

GENERAL SETTINGS BREAKER SETTINGS ACTIVE TABLE SETTINGS OSCILLOGRAPHY MASK FUNCTION PERMISSION

For the grouped as follows:

Only one setting table is active at a given time, and this is the table used by the system to run the different functions included in it.

There is an "ACTIVE TABLE" setting that determines the settings table that is active at a given moment. The active settings table can be changed by means of up to 2 digital inputs, referred to as "ACTIVE TABLE

SELECT 0" and "ACTIVE TABLE SELECT 1" which allow up to 4 combinations from 0 to 3. To do this it is necessary to configure (using GE-INTRO software) two inputs to have these meanings. For applications which require less tables (up to 2) it is possible to use only one input.

The selected combination is obtained from the binary coding of the 2 inputs mentioned (see following table). The 0-0 means selecting the table indicated in the "ACTIVE TABLE" setting, and numbers 0-1 to 1-1 select tables 1 to 3 respectively

specific

settings, the DBF allows to have up to 3 independent setting tables. These specific settings are

50BF SETTINGS INTERNAL ARC SETTINGS

Table Selection

INPUT-1

0 0 Selected by setting 01 1 10 2 11 3

Table Selection

INPUT-0

Active Table

NOTE: if the inputs are programmed and used, energizing them, this selection has priority over the "ACTIVE

TABLE" setting and the table which is in fact used is determined by the status of the digital inputs.

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2. OPERATION LOGIC

2.4.2 TIME SYNCHRONIZATION.

The DBF system includes an input for time synchronization. This input requires the connection of a device to supply a demodulated IRIG-B output. In this way coordinated universal time is measured to a high degree of accuracy and makes possible to tag events generated by the unit with a resolution of one millisecond.

The use of this input makes it possible to correlate data obtained from different units thanks to synchronization with GPS satellites. In this way it is possible to obtain very useful information for analysis, crossreferencing the information provided by different units for a given incident.

Alternatively, it is possible to synchronize units by means of communications, using the GE-LOCAL communications software, or manually by means of the HMI. If the IRIG-B input is used it has priority over time setting by communications, since the time read by IRIG-B is much more accurate.

2.4.3 CONFIGURABLE INPUTS AND OUTPUTS

2.4.3.1 Digital Inputs

The DBF system has 6 digital inputs (two groups of 3 inputs with one common in each group). The inputs can be configured by the user by means of the GE-INTRO configuration program. Using the optional expansion board it is possible to increase the number of inputs up to a total of 14 (2 groups of 3 inputs with one common in each group and 4 groups of 2 inputs with one common in each group). See the external connections diagram for additional reference.

One of the following meanings can be assigned to any input: (For more detail about the configuration of the inputs, see GE-INTRO Instruction Book).

Function P/L

Unused input 50BF Initiate A L 50BF Initiate B L 50BF Initiate C L 3P BF Initiate L 52a pole A L 52a pole B L 52a pole C L 52b pole A L 52b pole B L 52b pole C L Latching Relays Reset P External Trigger P Active Table Select 0 L Active Table Select 1 L

(L) indicates Level input (P) indicates Pulse input

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