TECHNOLOGY TO THE FORE
SW ITC H G EAR
C O M P L E X
SF6-GAS CIRCUIT BREAKERS
FOR OUT-DOOR USE (72.5 TO 245 kV)
TECHNOLOGY TO THE FORE
SWITC H G EAR
C O M P L E X
INTRODUCTION
Crompton Greaves Ltd. is one of the leading manufacturers of SF 6 Gas Circuit Breakers in the world. We manufacture Gas
Circuit Breakers ranging from 6.6kV to 420kV .
More than 13,000 Crompton Greaves SF6 Gas Circuit Breakers upto 420kV have been put into service in various
environments in many countries since 1983 where they are operating satisfactorily.
Our manufacturing and quality systems are ISO 9001 certified.
SFM TYPE SF 6 GAS CIRCUIT BREAKER (SPRING-SPRING MECHANISM)
Crompton Greaves manufactures SFM type Outdoor SF6 Gas Circuit Breakers (GCBs) ranging from 72.5kV to 245kV.
These GCBs are of live tank design, with motor / manual charged spring-opening spring-closing operating mechanism and
are capable of interrupting all possible switching duties. The breakers are single break interrupter design and employ
dual flow puffer action for current interruption ensuring high operational reliability and safety of power transmission
and distribution systems.
The GCBs are capable of clearing the severe rate of rise of recovery voltage due to short line faults and high recovery
voltage peak due to out of phase switching. Small currents such as capacitor bank switching current,
transformer magnetizing current, cable / line charging current, are interrupted smoothly without any re-strikes or
re-ignition and the over-voltages observed are minimum.
FEATURES
•
•
•
•
•
•
•
•
•
•
Simple and compact design.
Line to ground clearances as per customer specification.
Self aligning contacts for easy re-assembly.
Single break design.
High seismic withstand capability – earthquake safety.
Complete range tested at CESI, Italy; KEMA, Netherlands and CPRI, India.
Inspection / maintenance of pole unit possible without dismantling the breaker.
Easy erection.
No site adjustments.
Low operating noise levels.
CONSTRUCTION & OPERATION
Depending upon the application, type SFM GCBs are divided into two types as follows;
Three phase auto re-closing circuit breaker with one common mechanism for Transformer applications.
Single / Three phase auto re-closing circuit breaker with three separate spring mechanisms (for each phase) for Line
applications.
The breaker consists of three main parts :
1. Vertical porcelain units containing puffer type interrupter
2. Spring-spring operating mechanism and control equipment in a single housing
3. Base Frame and support columns
INTERRUPTING UNIT
The interrupting unit filled with pressurized SF6 gas is placed at the top of the pole and contains Stationary Contact,
Nozzle, Moving Contact, Puffer Cylinder and Fixed Piston (Fig.1). During opening operation (Fig.2), the Moving Contact
along with the Puffer Cylinder is pulled down. The Fixed and Moving contacts get separated and arc is formed between
fixed arcing contact and moving arcing contact. Motion of the Puffer Cylinder compresses SF6 gas against the Fixed
Piston thus generating a powerful SF6 gas blast through the Nozzle over the arc. After travelling through some distance,
the dielectric strength of the gap is raised sufficiently to extinguish the arc. The reliability of the system is further
enhanced by the single pressure dual flow puffer interrupter, which reduces the number of moving parts and auxilliary
systems in the circuit breaker. This principle is shown in Fig. 3.
Absorbent
Upper terminal
Contact support
SF6 gas
Fixed arcing contact
Fixed main contact
Interrupter porcelain
Nozzle
Moving main contact
Moving arcing contact
Piston
Puffer cylinder
Drive tube
Lower terminal
Contact
FIG. 1 : Closed position
FIG. 2 : Open position
Key
Fixed main contact
Live parts (moving parts)
Live parts (fixed parts)
Fixed arcing contact
Arc
Insulators
Nozzle
SF6 gas
Moving arcing contact
Moving main contact
Puffer cylinder
Contact
Piston
FIG. 3 : Interrupting principle
INTERRUPTER
SPRING - SPRING OPERATING MECHANISM
The spring-spring mechanism consists of two springs – Closing spring and Tripping spring. Closing spring is charged
through a motor driven cam, pawl and ratchet mechanism.
Fig.4 shows the Breaker in Closed position ( Closing spring charged )
Both closing spring and tripping spring are in charged position. The Tripping spring exerts counter clockwise torque on
the lever. At this stage a locking device called ‘Trip Holding Latch’ avoids lever movement. When the trip coil is energized,
the lever is released from locking device and rotates to attain the ‘Open’ position.
Fig.5 shows the Breaker in Open position
Tripping spring is in the relaxed condition. Closing spring exerts counter clockwise torque on the Cam and Ratchet wheel.
When the Closing coil is energized, the Cam rotates in counter clockwise direction and in turn, the Lever is rotated
clockwise. This lever motion closes the breaker and charges the Tripping spring at the same time.
Fig.6 shows Closed position ( Closing spring discharged )
Immediately after the breaker is closed, the spring charging motor gets activated. The closing spring is charged by the
ratchet, linked to the motor. When the closing spring is fully charged the Limit Switch disconnects the supply to the
motor and the closing -holding latch holds the compressed spring energy till next discharge.
Cam
Trip spring
Ratchet
Closing spring
Lever
Ratchet wheel
Closing-holding latch
Closing trigger
Trip-holding latch
Closing coil
Interrupter
Trip coil
Trip trigger
FIG. 4 : Closed position (closing spring charged)
FIG. 5 : Open position (closing spring charged)
FIG. 6 : Closed position (closing spring discharged)
SPRING OPERATING MECHANISM
PHASE A
VALVE E [406]
PHASE B
PHASE C
VALVE E [406]
VALVE E [406]
VALVE D [405]
O RING P18
[408]
TEMPERATURE
COMPENSATED GAS PRESSURE
GAUGE [402]
GAS PRESSURE
SWITCH [401]
GAS FEED PORT [403]
COVER [404]
ADAPTER V [713]
Spring Mechanism 72/145kV - Closing Spring
LARGE DIA HOSE [714]
VACUUM PUMP
[712]
GAS PIPE DIAGRAM
Spring Mechanism 72/145kV - Opening Spring (Rear View)
ROUTINE TESTING
All routine tests as specified in IEC 56 are conducted on the fully assembled GCBs at our factory. In addition to the
specified tests as per IEC, following tests are also carried out on each breaker.
1) Gas leakage test.
2) Speed and timing test.
3) Gas pressure switch test.
CG testing laboratory is fully equipped with the latest testing equipment viz.
1)
2)
3)
4)
5)
Full
600kV test transformer – Programmable logic control MUR 24A.
High precision mass spectometer type gas leak detector (with capability to detect leaks as low as 1 ppm).
Multi-channel breaker Speed / Time analyser.
Milli-Volt drop test set.
Primary injection test set.
testing before despatch of breaker ensures trouble free operation at site and complete customer satisfaction.
QUALITY AND SURFACE TREATMENT
All critical components and sheet metal stampings are manufactured on CNC machines ensuring high dimensional
consistency. All parts coming in contact with moisture are zinc/cobalt black passivated. All exposed ferrous parts are
treated to give high corrosion resistance. They are shot blasted, spray galvanised, primer coated and finally painted with
polyurethane based paint or epoxy paint ensuring excellent finish and protection. All joints are secured against loosening
by using torque wrenches and other suitable means. All hardwares are of Stainless steel or Hot Dip Galvanised.
TRANSPORT AND SITE INSTALLATION
All the circuit breakers are factory tested and then depending upon the type involved are partly dismantled into packing
units and despatched. All the subassemblies are individually wrapped to reduce the harmful effects of atmospheric air. For
exports, the breakers are despatched with seaworthy packing. The circuit breaker poles are filled with a small quantity of
2
SF 6 gas for transportation (at a gauge pressure of 0.5 kg/cm ) to avoid moisture ingress and site evacuation. Site
installation is simple and no site adjustments are required during erection and commissioning, all main adjustments /
settings are done in the factory prior to delivery.
CUSTOMER SUPPORT AND AFTER SALES SERVICE
We provide solutions to all possible technical requirements of customer through our highly qualified engineers having rich
experience in the field.
Our service engineers, technicians and authorized representatives can provide supervision of erection and commissioning
and after sales service at site.
GUARANTEED TECHNICAL PARTICULARS
72.5 - 245kV SF6 GAS CIRCUIT BREAKER ( SPRING - SPRING MECHANISM )
SN
DESCRIPTION
1. TYPE REFERENCE
2. RATED VOLTAGE
3. RATED LIGHTNING IMPULSE
WITHSTAND
4. RATED POWER FREQUENCY
WITHSTAND
5. CREEPAGE DISTANCE (TOTAL)
6. APPLICABLE STANDARDS
7. TYPE OF MECHANISM
8. RATED NORMAL CURRENT
9. RATED OPERATING SEQUENCE
10.RATED FREQUENCY
11.RATED DURATION OF SHORT
CIRCUIT
12.RATED CLOSING / TRIPPING
VOLTAGE
13.CURRENT OF CLOSING /
TRIPPING COIL
14.RATED BREAK TIME
15.RATED CLOSING TIME
16.RATED SHORT CIRCUIT
BREAKING CURRENT
17.RATED SHORT CIRCUIT MAKING
CURRENT
18.RATED LINE CHARGING BREAKING
CURRENT AND OVER VOLTAGE
19.RATED CABLE CHARGING BREAKING
CURRENT AND OVER VOLTAGE
20.RATED SINGLE CAPACITOR BANK
BREAKING CURRENT AND OVER
VOLTAGE.
21.RATED OUT OF PHASE BREAKING
CURRENT
22.FIRST POLE TO CLEAR FACTOR
23.AUXILLIARY CONTACTS
24.SF6 GAS PRESSURE (AT 20°C)
- NORMAL
- GAS FEED ALARM
- LOCKOUT
25.DIMENSIONS
A
B
D
H
26.WEIGHT (Approx.)
UNITS
:
:
:
kV
3 PHASE AUTO RE-CLOSING
1 PHASE AUTO RE-CLOSING
70-SFM-32B 120-SFM-32B 120-SFM-32B 120-SFM-40B 70-SFM-32B 120-SFM-32B 120-SFM-32B 200-SFM-40S
72.5
123
145
145
72.5
123
145
245
kVp
350
550
650
650
350
550
650
1050
:
kV
160
230
275
275
160
230
275
460
:
:
:
:
:
:
mm
A
Hz
1815
3075
3625
3625/4595
1815
3075
IEC : 60056, BSS : 5311, JEC : 181
SPRING-SPRING
3150
0-0.3 sec-CO-3 min-CO / CO-15 sec-CO
50
50/60
3625
6125
:
sec.
3
:
V
110/125/220 V DC
:
A
7 A max. at 110 V DC
:
:
mS
mS
:
kA
31.5
40
31.5
40
:
kAp
80
100
80
100
:
A / pu
10/<2.5
:
A / pu
250/<2.5 160/400/<2.5 160/400/<2.5 160/400/<2.5 250/<2.5 160/400/<2.5 160/400/<2.5 250 / <2.5
:
A / pu
250/<2.5
:
kA
:
:
-
: Kg/cm2
: Kg/cm2
: Kg/cm2
:
:
:
:
:
mm
mm
mm
mm
Kg
50/60
50
60
130
50/<2.5
400/<2.5
50/<2.5
400/<2.5
7.9
50/<2.5
400/<2.5
60
150
10/<2.5
50/<2.5
250/<2.5
50/<2.5
400/<2.5
10
400/<2.5
125/<2.5
400/<2.5
7.9
10
1.5
1.3
8 NO + 8 NC
5
4.5
4
8 NO + 8 NC / POLE
6
5.5
5
1100 /1700
3070
1600
4038
1100
1700
3490
2000
4908
1400
1700
4010
2000
5612
1450
7
6.5
6
5
4.5
4
1700
4010
2000
5502
1450
3470
3070
—
4038
2100
6
5.5
5
3470
3490
—
4908
2360
7
6.5
6
3470
4010
—
5428
2460
4600
4602
—
7146
3000
OPTIONALS
SN
DESCRIPTION
1. CREEPAGE DISTANCE
2. CLOSING / TRIPPING COIL VOLTAGE
3. CLEARANCE OF LIVE PARTS TO
GROUND
4. MAX. ALTITUDE ABOVE SEA LEVEL
5. AUXILLIARY CONTACTS
6. SEISMIC ACCELERATION
UNITS
3 PHASE AUTO RE-CLOSING
mm / kV 31,35,40 31,35,40,45 31,35,40
V DC
48 / 60 / 125
m
g
1 PHASE AUTO RE-CLOSING
25,31
31,35,40 31,35,40,45 31,35,40
48 /50 / 125
31
125 / 250
AS PER CUSTOMER SPECIFICATIONS
1700
1000
1000
10 NO + 10 NC
0.3 / 0.4
1000
0.3
1700
1000
1000
10 NO + 10 NC / POLE
0.3 / 0.4
1000
Dimensional Details
Foundation Plan Details
THREE PHASE AUTO RECLOSING TYPE GCB
72.5 - 145 kV breaker (1 - break)
A
A
INTERRUPTER
PORCELAIN
700
280
280 525
700
SUGGESTED TRENCH
FOR CABLE ENTRY
SUPPORT COLUMN
CEMENT
80
300
2220
B
MECHANISM HOUSING
240
H
BASE FRAME
FLANGE
(340x300)
376
SUPPORT PORCELAIN
250
795
D
CONCRETE LEVEL
GROUND LEVEL
D
SINGLE PHASE AUTO RECLOSING TYPE GCB
a) 72.5 - 145 kV breaker (1 - break)
A
INTERRUPTER
PORCELAIN
SUPPORT
PORCELAIN
A
A
FLANGE CEMENT
(340x300)
700
280
A
240
H
300
BASE FRAME
MECHANISM
HOUSING
B
250
80
1085
2220
700
SUPPORT
COLUMN
FOUNDATION DESIGN
DETAILS FOR VIEW "A","B" AND "C"
CONCRETE LEVEL
GROUND LEVEL
1085
PH.A
1085
PH.B
CABLE TRENCH
1085
PH.C
b) 245 kV breaker (1 - break)
A
PHASE ‘R’
INTERRUPTING
PORCELAIN
A
‘A’
PHASE ‘B’
PHASE ‘Y’
‘B’
150
490
1000
180
80
2128
540
= =
B
250
50
150
250
‘E’
800
CONCRETE
LEVEL
520
520
520
100
LEVEL OF UNDRILLED
GLAND PLATE
540
813
‘x’
A
CONTROL
CABLE
1200
150
520
==
H
SUPPORTING
PORCELAINS
A
SECTION ‘E’-‘E’
‘E’
10470
GROUND LEVEL
Ø30
CL
100
DETAILS OF ‘X’
Foundation Bolt Details
Terminal Pad Details
ø14,7 HOLES
Ø18 DRILL
4 HOLES
100
-8-M24 FOUNDATION BOLTS
250
M24 FOUNDATION
BOLTS
16.0
64 44.5
140
40 40 40
140
44.5
Ø14 DRILL
4 HOLES
15.5
44.5 64
140
Ø18 DRILL
4 HOLES
197.0
DETAILS OF UPPER & LOWER
TERMINAL PADS
245 kV (1Ø)
44.5
140
35 40 35
44.5
44.5
19.5
Ø14 DRILL
4 HOLES
12
R180
15.5
100
FOUNDATION BOLTS
72.5 to 145 kV (1Ø / 3Ø)
225.0
44.5 44.5
400
400
400
400
50
SUPPORT STRUCTURE
72.5 to 145 kV (1Ø / 3Ø)
DETAILS ‘B’
LOWER TERMINAL PADS
DETAILS ‘A’
UPPER TERMINAL PADS
245 kV (1Ø)
Power Systems
A Business Unit of Crompton Greaves Ltd.
SF6 Switc
hg
ear Divn.
Switchg
hgear
hg
ear Comple
x
Switchg
hgear
Complex
Switc
A-3, MIDC, Ambad, Nashik - 422 010, India
Tel:
(+91) 253 382271
Fax:
(+91) 253 382219/381247
E-mail: exports@cglmail.com (Exports)
mktg@cglmail.com (General)
URL: www.cgswgear.com
Regd. Office: 6th Floor, CG House, Dr. Annie Besant Road, Prabhadevi, Mumbai - 400 025, India.
Quality through care. Care through quality.
The Thapar Group
CG-S&C/EXP/Cat.No.SF6-105/9/01/5000
Data subject to change