Digital Breaker Failure
Phase and ground backup protection
for the primary circuit breaker.
A pplicat ions
■ Backup protection for prim ary circuit
breaker
Prot ect ion and Cont rol
■ Tw o step instantaneous and/or tim e delayed
breaker failure
■ Independent tim er per phase for the first step
■ Phase instantaneous overcurrent
■ Ground instantaneous overcurrent
■ Three phase direct trip
■ Fast tripping logic by using a second set of
level detectors per phase and an independent tim er
■ Internal arcing protection
■ Operation failure detection
■ Three settings groups
■14 configurable inputs
■16 outputs (11 configurable)
M onit oring and M et ering
■Current m etering
■Breaker health m onitoring
■Event recorder, last 165 events
■Oscillography, 4 records of 62 cycles
■Phase sequence selection
U ser Int erf aces
■Keypad and display
■17 LED indicators
■3 com m unications ports
■RS232 ports
■Fiber optics available
D escript ion
The DBF is a digital breaker fail-ure relay that provides phase and ground backup protection if the p r i m ar y ci r cu i t b r eaker f ai l s t o clear a system fault.
Breaker failure protection is criti-cal i n an y b acku p r el ay i n g sch em e. Th i s p r o t ect i o n m u st h av e n o t o n l y sen si t i v i t y an d d ep en d ab i l i t y, b u t al so a h i g h l ev el o f secu r i t y b ecau se i t i s protecting the busbars. The relia-bility m ust also be the sam e as that of a busbar protection relay. By using digital technology the o p er at i o n t i m e o f t h e DBF h as been im proved.
An associated function protects against electrical arcing betw een the contacts of the breaker w hen i t i s o p en ed . Th i s w i l l h el p t o prevent dam age to the breaker. Th i s f u n ct i o n u ses t h r ee v er y sensi ti v e ov er curr ent detector s set to the line capacitive current. Three setting groups are avail-ab l e, w i t h t h e act i v e g r o u p selected by a setting or an input. There are 14 configurable inputs and 16 outputs (11 configurable). Th e DBF m et er s t h e cu r r en t continuously. It also m onitors the breaker health I2t value. It has an event recorder that can store the last 165 events w ith a 1 m s reso-l u t i o n . It can st o r e u p t o 4 o sci l l o g r ap h y r eco r d s w i t h 66 cycles each.
The local user interface includes a keypad and display. There are 17 LED i n d i cat o r s, o n e a t w o colored system alarm , and 16 red co n f i g u r ab l e t o an y o f t h e 32 alarm s available. There are three co m m u n i cat i o n s p o rt s, o n e o n the front panel and tw o on the
Prot ect ion and
Cont rol
Overcurrent Protection
The DBF’s three phase overcur-rent protection (50PBF) consists of single or three-phase breaker failure initiation units w ith inde-pendent pickups and tim e delays. It also has three phase direct trip protection (50XNF), w hich m ay be used for three phase breaker failure initiation w ithout overcur-r en t . Th e DBF al so i n cl u d es g r o u n d ov er cu rr en t p r o t ect i o n (50NBF).
Tw o step breaker failure opera-tion is included w here each step o p er at i o n m ay b e act i v at ed b y single, tw o or three phase over-current functions. Both steps are t i m e d el ay ed an d o ff er a w i d e range of settings.
U si n g i n d ep en d en t t i m er s p er phase for the first step perm its a co r r ect co o r d i n at i o n w i t h t h e second zone in case of evolving f au l t s i n si n g l e-p o l e t r i p p i n g schem es.
Th e f ast t r i p p i n g l o g i c p er m i t s accelerated tripping during three-phase faults. This is particularly u sef u l i n m ai n t ai n i n g p o w er system stability w here selecti ve fast tripping is appropriate.
Internal Arcing Protection
If an electrical arc exists betw een the contacts of an open breaker it can eventually destroy the break-er. Th e DBF u ses t h r ee v er y sensi ti v e ov er curr ent detector s set to the line capacitive current to protect against internal arcing.
Settings Groups
Th r ee g r o u p s o f set t i n g s ar e available for the DBF. The active
Inputs and Outputs
The enhanced m odel DBF has 14 configurable inputs, in groups of 2 and 3 inputs.
Th er e ar e 16 o u t p u t s w i t h t h e follow ing assignm ents:
■1 breaker failure pickup
■2 breaker failure fix tripping
contacts
■1 internal arc contact
■1 alarm contact
■5 spare configurable contacts
■6 latching relay contacts
(option-al)
Th e l o g i c f o r co n f i g u r ab l e outputs consists of a com bination of NOT, AND, and OR gates appli-cable to trips, alarm s and pickups of all the protection and control f u n ct i o n s, i n t er n al p r o t ect i o n status, control, digital inputs, etc. A basic DBF m odel is also avail-ab l e w h i ch i n cl u d es 6 co n f i g u r ab l e i n p u t s an d 10 outputs (5 of w hich are config-urable).
M onit oring and
M et ering
Breaker M onitoring
The breaker status is m onitored continuously. The cum ulative I2t v al u e i s st o r ed an d u sed f o r breaker health m onitoring.
Event Recorder
Oscillography
Th e DBF sy st em i n cl u d es an oscillography recorder. It can be activated by any of the protective functions pickup or trip or by an ex t er n al i n p u t . Reco r d s h av e a r eso l u t i o n o f 16 sam p l es p er cy cl e. U p t o 4 r eco r d s m ay b e stored w ith up to 66 cycles each, w ith pre-fault cycles adjustable betw een 2 and 10 cycles.
The DBF can store up to 4 oscillography records
Protection Status Self-checking
The DBF perform s self tests both at start up and continuously in the background during operation.
5
U ser Int erf aces
Keypad and Display
The DBF has a 20 button keypad an d a 2 l i n e b y 16 ch ar act er al p h an u m er i c LCD. Th i s al l o w s l o cal u ser i n t er f ace w i t h o u t a com puter.
LED Indicators
The DBF has 17 LED indicator s. One is a tw o color system alarm . Th e o t h er 16 ar e r ed , an d ar e co n f i g u r ab l e t o an y o f t h e 32 alarm s available. Each LED can b e co n f i g u r ed w i t h o r w i t h o u t m em ory.
Communications
The DBF has three com m unica-t i o n s p o r unica-t s, o n e o n unica-t h e f r o n unica-t panel w hich is connected to one o n t h e r ear p an el , an d a t h i r d independent rear panel port. The first tw o ports allow com m u-n i cat i o u-n t h r o u g h GE-LOCA L so ft w ar e, ei t h er l o cal l y w i t h a
laptop com puter, or rem otely to a protection dispatch center. This software allow s the user to visu-alize m easurem ents and status as w ell as the relay’s tim e synchro-nization.
The third port connects the user t o a co m m u n i cat i o n s n et w o r k, through GE-POWER softw are, to t h e p ar t o f a DDS i n t eg r at ed sy st em . Th ese ap p l i cat i o n s ar e p ar t o f GE-N ESIS (Gen er al El ect r i c N Et w o r k Su b st at i o n Integration Software) used by the DDS system .
GE-LOCAL software is provided for DBF com m unication
D im ensions
FRONT VIEW SIDE VIEW
CUTOUT & DRILLING PATTERN
19.00" (483)
3.40" (87)
10.35"
(263) 1.20"
(31)
0.28" Dia. (7) 4 Pl.
18.32" (465) 17.32" (440)
725700A2.dw g 3.52"
(89) 3.00"
(76) 0.26"(7)
Typical Wiring
B.F. INIT. PHASE A52/b - A
3 PHASE B.F. INIT.
D BF Technical Specif icat ions
O U T P U T S Signalling contacts:
Contact Capacity:
M aximum operating voltage: 380 VAC, 250 VDC
Continuous current: 8 A
M ake and carry: 8 A
Breaking capacity: 1760 VA
Tripping Contacts: Contact Capacity:
M aximum Operating Voltage: 440 VAC
Continuous Current: 16A
M ake and Carry: 30 A
Breaking: 4000 VA
IN P U T S Burdens:
Current Circuits: 0.5 VA for In= 5 A 0.1 VA for In= 1 A
DC Burden:
During operation: 12 W
Per each activated input: 8 mA/1W, Vaux: 125 VDC
PA C K A G IN G
Dimensions: 3.40" H x 19" W x 10.35" D (87 mm x 483 mm x 263 mm)
Weight:
Not packaged: 16.08 lbs (6 kg)
Packaged: 18.76 lbs (7 kg)
T Y P E T E S T S
Isolation Test Voltage: 2 kV, 50/60 Hz, 1 min
Surge Test Voltage: 5 kV peak, 0.5 J
Interference: Class III according to IEC 255-22-1
Electrostatic Discharge: Class IV according to IEC 255-22-2
Radio Interference: Class III according to IEC 255-22-3
Fast Transient: Class IV according to IEC 255-22-4
Sinusoidal Vibration: Class II according to IEC 255-21-1
Shock: Class I according to IEC 225-21-2
Radio Frequency Emission:
according to IEC 41B (Sec) 81 and EN55022 class B
Emisitivity: according to EN50081-2(* )
Susceptibility: according to EN50082-2(* )
E N V IR O N M E N T A L Temperature:
Storage: -40°C to +85°C
Operation: -20°C to +55°C
Humidity: Up to 95% w ithout condensing
M E C H A N IC A L C H A R A C T E R IS T IC S
• M etallic package in 19" rack and 2 units high • Frontal M M I w ith LCD and keypad • Six rear terminal blocks
• Protection class IP52 (according to IEC 529)
A P P R O V A L S
Compliant UL - UL listed for USA and Canada
C O M M U N IC A T IO N S
Local Communication:LCD alphanumeric display w ith tw o lines of 16 characters per line
20 button frontal keypad
Remote Communication
(local or remote PC and communication net): M ode: half duplex
Speed: 1200 to 19200 bps
Physical M edia:RS232 (ports 1, 2 and 3) Plastic fiber optic (port 3 optional)
Type of connector: HFBR-4516 Pow er supplied: -8 dBm Receptor’s sensitivity: -39 dBm Wave length: 660 nm Glass fiber optic (port 3 optional)
Type of connector: STA Pow er supplied: -17.5 dBm Receptor’s sensitivity: -24.5 dBm Wave length: 820 nm Synchronization: IRIG-B
• DB9 connector for RS232 ports on the front (1) and on the rear (2)
• DB9 connector for RS232 port on the rear (3), w ith 1 mm plastic fiber optic or 50/125 glass fiber optic option
M E T E R IN G
Frequency: 50/60 Hz
Rated Phase Current: 0.2 - 2.4 Inin steps of 0.01 A Range D
Rated Ground Current: 0.1-1.2 Inin steps of 0.01 A Range D
Auxiliary Voltage: 24 - 48 VDC ± 20% 110 - 250 VDC ±20%
P R O T E C T IO N Thermal Capacity:
Current circuits:
Continuously: 4 x In
During 3 sec: 50 x In
During 1 sec: 100 x In
TIM ERS
1 Phase Timers T1: 0.05 - 2 sec in steps of 0.01 sec
3 Phase Timers T2: 0.05 - 2 sec in steps of 0.01 sec
3 Phase W /O Current Timer T3: 0.05 - 2 sec in steps of 0.01 sec
2nd Stage Timer: 0.05 - 2 sec in steps of 0.01 sec
Internal Arc Timer T4: 0.1 - 2 sec in steps of 0.01 sec
* Specifications subject to change w ithout notice.
Ordering
To order select the basic model and the desired features from the Selection Guide below.
DBF
1 * * * * 1 1 1 * * * A
DBF DBF Digital Breaker Tripping 0 RS232 communications
1 Plastic fiber optic and RS232 communications 2 Glass fiber optic and RS232 communications 3 RS485 and RS232 communications
B Ranges: Phase: In= 1 A (0.2-2.4 A), Ground: In= 1 A (0.2-2.4 A) C Ranges: Phase: In= 5 A (1-12 A), Ground: In= 1 A (0.2-2.4 A) D Ranges: Phase: In= 5 A (1-12 A), Ground: In= 5 A (0.5-6 A) F Ranges: Phase: In= 5 A (0.5-6 A), Ground: In= 1 A (0.2-2.4 A) G Ranges: Phase: In= 5 A (0.5-6 A), Ground: In= 1 A (0.1-1.2 A)
1 P1, P2, P3: M -Link communications protocol 2 P1, P2: M -Link protocol;
P3: M odBus®RTU communications protocol M Spanish language
D English language G 48-125 VDC pow er supply H 110-250 VDC pow er supply
00 Standard model
Special M odels:†
MOD 04A: Digital inputs voltage: 48 VDC±20%
MOD 05A: DIV: 110 VDC ±20%
MOD 06A: DIV: 125 VDC ±20% w w w .G Ein d u s t r ia l.c o m / p m
