1ZSE 2750-102 en, Rev. 7
Transformer bushings, type GOB
Technical guide
This Technical Guide has been produced to allow transformer manufacturers, and their
designers and engineers, access to all the technical information required to assist them
in their selection of the appropriate Transformer Bushing. The Guide should be used in
conjunction with the Selection Guide to allow the optimum selection to be made.
The technical information pertaining to bushings manufactured by ABB has been divided
into separate documents, with one document for each type.
The information provided in this document is intended to be general and does not cover
all possible applications. Any specific application not covered should be referred directly
to ABB, or its authorized representative.
ABB makes no warranty or representation and assumes no liability for the accuracy of
the information in this document or for the use of such information. All information in this
document is subject to change without notice.
Contents
Design________________________________________ 4
Test tap__________________________________ 5
Testing________________________________________ 5
Test tap adapter____________________________ 5
Electrical data__________________________________ 6
Common specifications___________________________ 6
Conductor loading_______________________________ 7
Overloading of bushings_____________________ 7
Short-time current__________________________ 7
52 – 170 kV
Dimensions____________________________________ 8
Bushings without oil level gauge_______________ 8
Shed form________________________________ 9
Dimensions____________________________________ 10
Bushings with oil level gauge_ ________________ 10
Shed form________________________________ 11
Ordering particulars______________________________ 12
Bushings without oil level gauge_______________ 12
Ordering particulars______________________________ 14
Bushings with oil level gauge_ ________________ 14
Connection details_______________________________
Inner terminal_ ____________________________
Solid rod conductor_________________________
Outer terminal_____________________________
Separate terminal plate with bolts______________
Arcing horns_ _____________________________
16
16
16
17
17
17
300 kV
Dimensions____________________________________ 18
Type GOB 1050____________________________ 18
Shed form________________________________ 18
Ordering particulars______________________________ 19
Type GOB 1050____________________________ 19
Recommendations for positioning___________________ 20
Design
The bushing is built up around a centre tube on which the condenser body
is wound. The upper insulator, lower insulator and mounting flange are held
between the end plates by the centre tube. Sealing is accomplished by oilresistant rubber gaskets in grooves.
The annular space between the condenser body and the porcelain is filled
with transformer oil. A gas-filled expansion space is left at the top. For GOB
bushings without oil level gauge the oil level can be checked by means of a
dipstick in the oil filling hole.
The lower end is shielded by an epoxy resin insulated aluminium shield.
The shield is integrated for 52–170kV, and separate for 300 kV bushings.
The inner terminal is attached to the centre tube by means of a throughgoing resilient pin which becomes locked when the outer terminal is
screwed on. This design, patented by ABB, ensures effective electrical
contact between the inner and outer terminals. The inner terminal can be
chosen for connection to leads either by brazing or crimping.
The outer terminal is available in aluminium or copper alloy and can be
supplemented by terminal plates of corresponding material.
The upper insulator is made in one piece of high quality electrical porcelain.
The mounting flange is manufactured of corrosion-resistant aluminium alloy.
The mounting flange, the top housing and the top washer are protected
by painting with a two-component primer and a grey-blue finishing coat of
paint. The standard colour is Munsell 5.5B 55/1.25.
Outer terminal stud
Oil filling holes
with sealing plug
Top
washer
Expansion space
Oil
Top
housing
Porcelain insulator
air side
Test tap
Mounting flange
Flange extension
Top
housing
Porcelain insulator
oil side
Condenser body
Prism
glass
Insulated shield
(integrated or
separate)
Oil filling
holes with
sealing plug
Fig. 1. Transformer bushing type GOB
4
The bushings are delivered oil-filled and ready for use.
If the bushing is mounted with an inclination of more than 45° from the
vertical, special measures may have to be taken to ensure the condenser
body is fully submerged in oil. Further information can be obtained on
request.
Test tap
The outer conducting layer of the
condenser body is connected to
an insulated test tap on the flange.
During operation the test tap cover
must be screwed on, in order to earth
the bushing. The max. test voltage of
the tap is 2 kV, 50 Hz for 1 minute.
Max. service voltage is 600 V.
Fig. 2. Test tap.
goh_0010
Testing
During the manufacture and on its completion the bushing is subjected
to a number of routine tests, in compliance with IEC 60137. A tightness
test is carried out on the assembled bushing after the final drying and
impregnation. The test is made with an oil overpressure of 180 kPa (1.8
bar) for 12 hours at ambient temperature. No sign of leakage is allowed.
Each bushing is subjected to a final electrical routine test. The test
is made at room temperature with the bushing submerged in oil.
Capacitance and tan δ are measured in steps up to the power frequency
withstand voltage, which is maintained for one minute. Capacitance and
tan δ are also measured at decreasing voltage at the same voltage levels
as before the one minute test.
Measurements for detection of internal partial discharge (PD
measurements) are also made. These measurements are carried out at
the same time as the power frequency withstand test. PD measurements
are made in steps up to the full test voltage and down. It is always
demonstrated that the PD value is max. 5 pC at test voltage equal to the
rated system voltage.
GOB 1050 is also routine tested with a dry lightning impulse voltage
withstand test.
Type tests have been carried out according to IEC 60137 and IEEE. Type
test reports are available on request.
Test tap adapter
For permanent connection of the
test tap to measuring circuits,
a test tap adapter is required.
Catalogue number 2769 531-D.
Fig. 3. Test tap adapter.
5
goh_0011
Electrical data
Type GOB
Rating
Routine test
Design data
Highest
voltage for
equipment Um
kV, RMS
Phase-toearth voltage
Uy
kV, RMS
Dry lightning
impulse
kV, peak
Wet power
frequency AC
kV, RMS
1 min. dry
50 Hz
kV, RMS
Dry
switching
impulse
kV, peak
Wet
switching
impulse
kV, peak
250-800
52
52
250
105
120
230
-
250-1250
52
52
250
105
120
230
-
325-800
72.5
72.5
350
140
160
300
-
380-800
100
72.5
380
150
162
330
-
380-1250
100
72.5
380
150
162
330
-
450-800
123
90
450
185
195
410
-
550-800
170
123
550
230
260
470
-
550-1250
170
123
550
230
260
470
-
650-1250
170
145
650
275
300
580
-
750-1250
170
170
750
325
365
670
-
1050-1100
300
173
1050
510
510
810
750
Common specifications
Application:
Transformers
Classification:
Oil impregnated paper, capacitance graded, outdoor-immersed bushing
Ambient temperature:
+40 to -40 °C, minimum value as per temperature class 2 of IEC 60137
(-60 °C according to GOST 10693-81 item 2.26)
Altitude of site:
< 1 000 m
Level of rain and humidity:
1-2 mm rain/min horizontally and vertically, as per IEC 60060-1
Pollution level:
According to specified creepage distance and IEC 60815 ("Guide for selection of insulators with
respect to polluted conditions")
Type of immersion medium:
Transformer oil. Maximum daily mean oil temperature 90 °C. Maximum temporary oil temperature
115 °C
Oil level below bushing flange:
Maximum 30 mm
Max. pressure of medium:
100 kPa overpressure
Markings:
Conforming to IEC/ IEEE
6
Conductor loading
The rated currents listed in this catalogue are the standardised values
according to IEC 60137 which, with the largest possible conductor, fulfil
the temperature rise test.
The GOB bushings fulfil the temperature rise test requirements according
to IEC 60137 and IEEE C57.19.00-1991.
Rated current of
bushing
A
Conductor
52 – 170 kV
Permissible current
300 kV
Permissible current
IEC, A
IEEE, A
IEC, A
IEEE, A
800
Solid rod LF 170 019
800
730
1100, 1250
Solid rod LF 170 052
1250
1200
1100
1000
800, 1100, 1250
2
Stranded cable 50 mm
165
150
155
130
800, 1100, 1250
Stranded cable 70 mm2
225
210
190
160
800, 1100, 1250
Stranded cable 95 mm
300
285
240
195
800, 1100, 1250
Stranded cable 150 mm2
475
415
330
275
1100, 1250
2
Stranded cable 185 mm
530
460
380
320
1100, 1250
Stranded cable 285 mm2
665
570
540
450
2
Overloading of bushings
If the conductor for the bushing is selected with 120 % of the rated current
of the transformer, the bushing is considered to be able to withstand the
overload conditions stated in IEC 60354 without further clarifications or
tests, according to IEC 60137.
Short-time current
The rated thermal short-time current (Ith) is calculated according to IEC
60137. Read more in product information 2750 515-118.
For draw-lead of stranded copper, values are given for 100 mm2. For other
areas the short-time current is directly proportional to the area.
Conductor
Rated
current
A
Area
mm2
Short-time current (Ith)
1s
kA, RMS
2s
kA, RMS
Solid rod
800
-
30
21
52
Solid rod
1100/1250
-
70
50
125
Stranded draw-lead
365
100
9.6
6.8
17
7
Dynamic
current (Id)
kA, peak
52 – 170 kV
Dimensions
Bushings without
oil level gauge
Draw
lead
length =
Fig. 4.2.
Top design
Fig. 4.3
Top design
Fig. 4.4
Fig. 4.1. GOB design
The bushings can be provided
with a longer shield L9 + 50 mm,
in which case dimensions L, L1
and L5 also increase by 50 mm.
1)
n1 Holes
D = 16
Type
GOB
Rated Cat. No.
current
A
250
800
250
1250
325
800
380
800
380
1250
450
800
550
800
550
1250
650
1250
750
1250
LF 123 013015083LF 123 017019085LF 123 025027089LF 123 037039095LF 123 041043097LF 123 049051053LF 123 061063107LF 123 065067109LF 123 073075113LF 123 077078079-
Space Net
for
mass
current kg
transformer
mm
300
500
300
500
300
500
300
500
300
500
300
500
100
300
500
100
300
500
150
300
500
200
300
500
23
25
27
26
29
31
27
31
35
33
37
39
37
39
43
42
45
48
70
73
77
105
109
115
116
122
126
180
190
200
Top
Dimensions in mm
design L1)
L11)
L2
acc. to
Fig. 6
2
2
3
2
2
3
2
2
3
2
2
3
2
2
3
2
2
3
2
3
3
2
3
3
2
3
3
2
3
3
998
1258
1558
1063
1323
1623
1198
1458
1758
1303
1543
1843
1368
1608
1908
1473
1713
2013
1823
2108
2308
1868
2153
2353
2153
2413
2613
2468
2683
2883
240
500
700
255
515
715
295
555
755
345
585
785
360
600
800
345
585
785
495
680
880
495
680
880
580
740
940
685
800
1000
8
590
590
690
605
605
705
735
735
835
790
790
890
805
805
905
960
960
1060
1160
1260
1260
1170
1270
1270
1370
1470
1470
1580
1680
1680
L3
L4
L51)
L6
L7
L8
L91)
65
555
555
655
580
580
680
700
700
800
755
755
855
780
780
880
925
925
1025
1125
1225
1225
1145
1245
1245
1345
1445
1445
1555
1655
1655
60
260
460
260
460
260
460
240
440
240
440
240
440
95
280
480
95
280
480
120
280
480
165
280
480
480
70
15
480
70
25
625
70
15
680
70
15
680
70
25
850
70
15
1050
60
25
1050
60
30
1250
60
30
1460
60
30
65
93
98
98
98
60
68
60
70
75
60
60
75
60
90
100
100
100
52 – 170 kV
Shed form
The shed form is of the anti-fog type with alternating long and short
sheds. For each pair of sheds the ratio between nominal creepage
distance and the axial length is 3.43
and the ratio between protected and
nominal creepage distance is 0.40.
According to IEC 60815 the creepage
factor C.F. is <3.2 and the profile factor
P.F. is >1.1.
For special customer demands
regarding creepage distance, other
shed forms may be used.
Fig. 4.5. Shed form, GOB 52 – 170 kV.
Dimensions are subject to modification without notice.
D1
D2
D3
D4
D5
D6
D7
D8
D10
n1
R1
R2
T
86
22
86
115
88
185
225
230
46
6
8
6
16
Creepage distance
Cantilever load
total
protected Max.
60 s
mm
mm
permitted
Test
loading
N
perpendicular
to the
terminal
N
1500±50 580
1800
2340
101
34
112
120
101
250
290
245
70
8
12
10
16
1500±50
580
3000
4000
95
22
86
115
96
185
225
230
46
6
8
6
16
1980±50
775
1500
1950
95
22
86
115
96
185
225
240
46
6
8
6
16
2210±70
870
1400
1800
112
34
112
120
112
250
290
245
70
8
12
10
16
2210±70
870
2900
3750
95
22
86
115
96
185
225
245
46
6
8
6
16
2720±80
1060
1150
1500
126
22
118
145
150
250
290
280
50
8
12
12
18
3430±100 1350
1300
1700
160
34
140
175
200
290
335
300
70
12
15
15
20
3430±100 1350
2400
3100
160
34
140
175
200
290
335
305
70
12
15
15
20
4080±110 1620
2600
3380
184
34
140
230
184
290
335
350
70
12
15
15
20
4800±150 1700
2600
3350
9
52 – 170 kV
Dimensions
Bushings with
oil level gauge
Draw
lead
length =
Fig. 5.2.
Top design
Fig. 5.3
Top design
Fig. 5.1. GOB design.
Fig. 5.4
n1 Holes
D = 16
Type
GOB
Rated Cat. No.
current
A
250
800
250
1250
325
800
380
800
380
1250
450
800
550
800
550
1250
650
1250
750
1250
LF 123 171173175LF 123 167168169LF 123 177179181LF 123 183185187LF 123 101102103LF 123 145147149LF 123 189190191LF 123 142143144LF 123 192193194LF 123 104105106-
Space Net
for
mass
current kg
transformer
mm
300
500
300
500
300
500
300
500
300
500
300
500
100
300
500
100
300
500
150
300
500
200
300
500
24
26
28
28
30
33
28
32
36
34
38
40
38
41
44
43
46
49
71
74
78
106
110
116
118
124
128
187
197
207
The bushings can be provided
with a longer shield L9 + 50 mm,
in which case dimensions L, L1
and L5 also increase by 50 mm.
1)
Top
Dimensions in mm
design L1)
L11)
L2
acc. to
Fig. 6
2
2
2
2
2
2
2
2
2
3
1138
1398
1598
1203
1463
1663
1338
1598
1798
1443
1683
1883
1508
1748
1948
1613
1853
2053
1963
2148
2348
2008
2193
2393
2293
2453
2653
2718
2833
3033
240
500
700
255
515
715
295
555
755
345
585
785
360
600
800
345
585
785
495
680
880
495
680
880
580
740
940
685
800
1000
10
L3
L4
L51)
L6
L7
L8
L91)
730
65
695
60
480
70
15
745
65
720
75
480
70
25
875
93
840
60
625
70
15
930
98
895
60
680
70
15
945
98
920
75
680
70
25
1100
98
1065
60
850
70
15
1300
60
1265
90
1050
60
25
1310
68
1285
100
1050
60
30
1510
60
1485
100
1250
60
30
1830
70
1805
100
260
460
260
460
260
460
240
440
240
440
240
440
95
280
480
95
280
480
120
280
480
165
280
480
1460
60
30
52 – 170 kV
Shed form
The shed form is of the anti-fog type with alternating long and short
sheds. For each pair of sheds the ratio between nominal creepage
distance and the axial length is 3.43
and the ratio between protected and
nominal creepage distance is 0.40.
According to IEC 60815 the creepage
factor C.F. is <3.2 and the profile factor
P.F. is >1.1.
For special customer demands
regarding creepage distance, other
shed forms may be used.
Fig. 5.5. Shed form, GOB 52 – 170 kV.
Dimensions are subject to modification without notice.
D1
D2
D3
D4
D5
D6
D7
D8
D10
n1
R1
R2
T
86
22
86
140
88
185
225
230
46
6
8
6
16
Creepage distance
Cantilever load
total
protected Max.
60 s
mm
mm
permitted
Test
loading
N
perpendicular
to the
terminal
N
1500±50 580
1800
2340
101
34
112
140
101
250
290
245
70
8
12
10
16
1500±50
580
3000
4000
95
22
86
140
96
185
225
230
46
6
8
6
16
1980±50
775
1500
1950
95
22
86
140
96
185
225
240
46
6
8
6
16
2210±70
870
1400
1800
112
34
112
140
112
250
290
245
70
8
12
10
16
2210±70
870
2900
3750
95
22
86
140
96
185
225
245
46
6
8
6
16
2720±80
1060
1150
1500
126
22
118
200
150
250
290
280
50
8
12
12
18
3430±100 1350
1300
1700
160
34
140
265
200
290
335
300
70
12
15
15
20
3430±100 1350
2400
3100
160
34
140
265
200
290
335
305
70
12
15
15
20
4080±110 1620
2600
3380
184
34
140
265
184
290
335
350
70
12
15
15
20
4800±150 1700
2600
3350
11
52–170 kV
Ordering particulars
When ordering, please state:
■■ Type and catalogue number for bushings.
■■ Catalogue number for inner and outer terminal
assembly.
■■ Additional accessories or modifications.
■■ Test required, in addition to the normal routine tests.
■■ Test tap adapter, if required.
Bushings without oil level gauge
Note:
The catalogue number should have one of the following
letters added to it, to indicate the type of insulator and
oil end shield:
–K Normal oil end shield, brown porcelain
–L Normal oil end shield, light grey porcelain
–M Longer oil end shield, brown porcelain
–N Longer oil end shield, light grey porcelain
Oil end
shield
Bushings
Connection details, Cat. No. LF 170
Type
GOB
Rated Cat. No.
current
A
250
800
250
1250
325
800
380
800
380
1250
450
800
550
800
550
1250
650
1250
750
1250
LF 123 013015083LF 123 017019085LF 123 025027089LF 123 037039095LF 123 041043097LF 123 049051053LF 123 061063107LF 123 065067109LF 123 073075113LF 123 077078079-
Space for
Bushing tube
current
(See fig.)
transformer D2, mm
mm
22
300
500
34
300
500
22
300
500
22
300
500
34
300
500
22
300
500
100
22
300
500
100
34
300
500
150
34
300
500
200
34
300
500
Inner terminal stud
For crimping or brazing
Conductor area
50 mm2
70 mm2
95 mm2
010-M
010-N
010-L
For brazing
Conductor area
<150 mm2 <285 mm2
011-S
-
Undrilled
with pilot
hole
011-U
-
-
-
-
011-T
011-V
010-M
010-N
010-L
011-S
-
011-U
010-M
010-N
010-L
011-S
-
011-U
-
-
-
-
011-T
011-V
010-M
010-N
010-L
011-S
-
011-U
010-M
010-N
010-L
011-S
-
011-U
-
-
-
-
011-T
011-V
-
-
-
-
011-T
011-V
-
-
-
-
011-T
011-V
12
52–170 kV
LF 170 019800 A
Outer terminal assembly
LF 170 0521250 A
Solid rod conductor
Stud with O-ring and locking pin
Aluminium
Copper alloy
001-A
002-A
Separate terminal plate with bolts
Aluminium
Tin-plated copper
014-A
021-A
001-B
002-B
014-A
021-A
001-A
002-A
014-A
021-A
001-A
002-A
014-A
021-A
001-B
002-B
014-A
021-A
001-A
002-A
014-A
021-A
001-A
002-A
014-A
021-A
001-B
002-B
014-A
021-A
001-B
002-B
014-A
021-A
001-B
002-B
014-A
021-A
13
Alt. 1
019 -A
-D
-E
052 -A
-D
-E
019 -F
-K
-L
019 -M
-R
-S
052 -V
-Z
-AA
019 -BL
-BM
-BP
019 -T
-X
-Y
052 -AM
-AN
-AR
052 -F
-K
-L
052 -M
-R
-S
Alt. 2
019 -B
-C
052 -B
-C
019 -G
-H
019 -N
-P
052 -X
-Y
019 -BN
-BR
019 -U
-V
052 -AP
-AS
052 -G
-H
052 -N
-P
Arcing horns
Mass kg
2.6
3.3
4.2
6.8
8.4
10.6
3.1
3.9
4.7
3.5
4.2
5.0
8.6
10.4
12.7
4.0
4.7
5.5
4.9
5.7
6.3
12.0
14.1
15.5
14.0
15.9
17.5
16.3
18.0
19.5
004 -A
-A
-B
004 -A
-A
-B
004 -A
-A
-B
004 -A
-A
-B
004 -B
-B
-B
004 -B
-B
-C
004 -B
-C
-C
004 -B
-C
-C
005 -A
-B
-B
005 -B
-E
-E
52–170 kV
Ordering particulars
When ordering, please state:
■■ Type and catalogue number for bushings.
■■ Catalogue number for inner and outer terminal
assembly.
■■ Additional accessories or modifications.
■■ Test required, in addition to the normal routine tests.
■■ Test tap adapter, if required.
Bushings with oil level gauge
Note:
The catalogue number should have one of the following
letters added to it, to indicate the type of insulator and
oil end shield:
–K Normal oil end shield, brown porcelain
–L Normal oil end shield, light grey porcelain
–M Longer oil end shield, brown porcelain
–N Longer oil end shield, light grey porcelain
Oil end
shield
Bushings
Connection details, Cat. No. LF 170
Type
GOB
Rated Cat. No.
current
A
250
800
250
1250
325
800
380
800
380
1250
450
800
550
800
550
1250
650
1250
750
1250
LF 123 171173175LF 123 167168169LF 123 177179181LF 123 183185187LF 123 101102103
LF 123 145147149LF 123 189190191LF 123 142143144LF 123 192193194LF 123 104105106-
Space for
Bushing tube
current
(See fig.)
transformer D2, mm
mm
22
300
500
34
300
500
22
300
500
22
300
500
34
300
500
22
300
500
100
22
300
500
100
34
300
500
150
34
300
500
200
34
300
500
Inner terminal stud
For crimping or brazing
Conductor area
50 mm2
70 mm2
95 mm2
010-M
010-N
010-L
For brazing
Conductor area
<150 mm2 <285 mm2
010-S
-
Undrilled
with pilot
hole
011-U
-
-
-
-
011-T
011-V
010-M
010-N
010-L
010-S
-
011-U
010-M
010-N
010-L
010-S
-
011-U
-
-
-
-
011-T
011-V
010-M
010-N
010-L
010-S
-
011-U
010-M
010-N
010-L
010-S
-
011-U
-
-
-
-
011-T
011-V
-
-
-
-
011-T
011-V
-
-
-
-
011-T
011-V
14
52–170 kV
LF 170 019800 A
Outer terminal assembly
LF 170 0521250 A
Solid rod conductor
Stud with O-ring and locking pin
Aluminium
Copper alloy
001-A
002-A
Separate terminal plate with bolts
Aluminium
Tin-plated copper
014-A
021-A
001-B
002-B
014-A
021-A
001-A
002-A
014-A
021-A
001-A
002-A
014-A
021-A
001-B
002-B
014-A
021-A
001-A
002-A
014-A
021-A
001-A
002-A
014-A
021-A
001-B
002-B
014-A
021-A
001-B
002-B
014-A
021-A
001-B
002-B
014-A
021-A
15
Alt. 1
019 -AM
-AS
-BB
052 -BC
-BF
-BG
019 -AN
-AU
-BD
019 -AP
-AX
-BF
052 -BK
-BN
-BP
019 -BS
-BT
-BV
019 -AR
-AZ
-BH
052 -AT
-AU
-AV
052 -AD
-AE
-AG
052 -AZ
-BA
-AK
Alt. 2
019 -AT
-BC
052 -BD
-BE
019 -AV
-BE
019 -AY
-BG
052 -BL
-BM
019 -BU
-BX
019 -BA
-BK
052 -AX
-AY
052 -AF
-AH
052 -BB
-AL
Arcing horns
Mass kg
3.0
3.7
4.3
7.7
9.3
10.8
3.5
4.3
4.8
3.9
4.6
5.1
9.6
11.4
12.6
4.4
5.1
5.6
5.3
5.8
6.4
13.0
14.4
15.8
14.9
16.1
17.7
18.0
19.0
20.5
004 -B
-B
-B
004 -B
-B
-B
004 -B
-B
-B
004 -B
-B
-B
004 -B
-B
-B
004 -C
-C
-C
004 -C
-C
-C
004 -C
-C
-C
005 -B
-B
-B
005 -F
-F
-F
52 – 170 kV
Connection details
Inner terminal
Stud made of copper for connection of draw lead.
The inner terminal must be provided with an outer
terminal.
Fig. 6. Inner terminal.
Material and
design
Copper for
crimping or
brazing
Copper for
brazing only
Conductor area
mm2
Cat. No.
Dimensions
mm
Mass
kg
D1
D2
L
-M
11
14.5
35
0.3
70
-N
13
17
35
0.3
95
-L
15
20
35
0.3
50
LF 170 010
≤ 150
-S
18
20
35
0.3
undrilled
LF 170 011
-U
5
20
35
0.3
≤ 285
-T
29
32
20
0.6
undrilled
-V
5
32
20
0.6
Solid rod conductor
The rod is produced from electrolytic copper and is divided into two parts.
For the 800 A conductor the two parts are held together by a centre bolt
with a resilient locking pin. For the
1100/1250 A conductor the two
parts are connected by countersunk screws.
The lower part of the solid rod is
designed to enable connection by
brazing.
The solid rod conductor can be
divided either:
Alt. 1: 20 mm below the bushing
flange, or
Alt. 2: 20 mm below the upper end
of the bottom porcelain.
The solid rod conductor must be
provided with an outer terminal.
Fig. 7. Solid rod conductor.
Rated current 800 A
LF 170 019-
16
Rated current 1100/1250 A
LF 170 052-
52 – 170 kV
Outer terminal
Stud made of copper alloy or aluminium with O-ring and
locking pin. Other types can be provided on request.
Fig. 8. Outer terminal assembly.
Width across flats N
Material
Cat. No.
Aluminium
LF 170 001
Copper alloy
LF 170 002
Dimensions
mm
Mass
kg
For bushings
with D2
mm
D
L
N
-A
30
170
55
0.5
22
-B
30
205
66
0.8
34
-A
30
170
55
1.2
22
-B
30
205
66
2.3
34
Separate terminal plate with bolts
The separate terminal plate is used for connecting
the bushing to the line conductor.
Fig. 9. Separate terminal plate with bolts.
Material
Cat. No.
Aluminium
LF 170 014-A
Nickel-plated copper
LF 170 021-A
Arcing horns
Arcing horns of galvanised steel can be
mounted on the bushing.
The lower rod is fastened onto the flange with
one of the fixing screws and the upper rod by
means of a bracket on the outer terminal.
The gap distances for standard arcing horns
are shown in the table. Other gap distances
on request.
Fig. 10. Gap distances.
Type GOB
K
mm
C
mm
H
mm
250
230–440
315
112
325
320–580
315
112
380
400–620
315
112
450
400–780
315
112
550
620–960
315
114
650
700–1080
380
224
750
820–1290
380
224
1050
950–1840
420
410
17
300 kV
Dimensions
D=265
Type GOB 1050
L
L2
L7
When ordering, please state:
■■ Type and catalogue number for bushings.
■■ Catalogue number for inner and outer terminal assembly.
■■ Additional accessories or modifications.
■■ Test required, in addition to the normal routine tests.
■■ Test tap adapter, if required.
L6 180
20
Note:
The catalogue number should have one of the following
letters added to it, to indicate the type of insulator and oil
end shield:
–K Brown porcelain
–L Light grey porcelain
L4
D=355
L1
L3
D=200
D=34
D=450
D=400
12 holes
D=23
gob_0020
Dimensions are subject to modification without notice.
Rated
current
A
Cat. No.
1100
LF 123 281LF 123 280-
Space for
current
transformer
mm
Net
mass
kg
Dimensions in mm
Creepage
distance
Cantilever
load
L
L1
L2
L3
L4
L6
L7
total
mm
protected
mm
Max
N
Test
N
300
335
3690
930
2555
49
2530
600
350
3990
1230
2555
49
2530
300
2066
7500
3200
1250
3200
600
2066
7500
3200
1250
3200
Shed form
The shed form is of the anti-fog type with alternating long and short
sheds. For each pair of sheds the ratio between nominal creepage
distance and the axial length is 3.97 and the ratio between protected and
nominal creepage distance is 0.4.
67.5
Fig. 11.5. Shed form, GOB 300 kV.
31
10°
For special customer demands
regarding creepage distance,
other shed forms may be used.
R8
18°
According to IEC 60815 the
creepage factor C.F. is 3.7 and the
profile factor P.F. is >1.1.
70
R10
52.5
R4.5
gob_0021
18
300 kV
Ordering particulars
Type GOB 1050
M8
M8
D=7
20
D=32
L4
D=7
gob_0022
Fig. 11.1. Inner terminal.
Alt. 1 - 3
D=30
66
205
D=32
gob_0023
Fig. 11.2. Outer terminal.
28
D=28
156
gob_0025
R160
107
Fig. 11.3. Solid rod.
R6
D=105
The solid rod can be divided:
Alt. 1: 20 mm below the bushing flange
Alt. 2: 20 mm below the upper end of the bottom porcelain
Alt. 3: 210 mm above the bottom end of the bushing
R1
5
D=176
gob_0024
Fig. 11.4. Oil end shield.
Dimensions refer to the epoxy insulated shield. The thickness of the pressboard is 3 mm.
Connection details Cat. No. LF 170
Cat. No.
LF 123 281–
Inner terminal stud
Solid rod conductor
For brazing
Stud with O-ring and
locking pin
Conductor Undrilled
area
with pilot
<285 mm2 hole
Aluminium
Copper
alloy
Alt. 1
011-T
001-B
002-B
052
011-V
LF 123 280–
Alt. 2
-FD
-FA
19
052
Oil end shield
Alt. 3
-FE
-FB
052
Arcing
horns
Epoxy
Pressboard
insulated insulated
-FF
-FC
092-B
092-D
005-G
Recommendations for positioning
The maximum stresses in
the oil at the surface of the
shield insulation must be
limited to those values normal
for insulated conductors and
similar components in the same
transformer.
The adjacent recommendations
are intended as guide lines when
complete calculations are not
carried out.
Earthed
layer
Distance to
uninsulated detail
Type GOB
Internal insulation level
of transformer (kV)
R (mm)
250–800
170–70
65
250–95
75
170–70
75
250–95
85
250–95
75
325–140
100
325–140
100
380–150
105
325–140
105
380–150
110
380–150
105
450–185
125
450–185
130
550–230
155
450–185
140
550–230
160
550–230
160
650–275
185
650–275
185
750–325
210
850–360
240
950–395
260
1050–460
300
250–1250
325–800
380–800
380–1250
450–800
550–800
550–1250
650–1250
750–1250
1050–1100
ABB
Ludvika, Sweden
GOB 250
LF 123 013-K
No. 1ZSC 257 007
Um/Uy 52/52 kV Ir 800 A 50/60 Hz
LI / AC 250/120
kV
M 23 kg L 240 mm
0-90 °
C1 128 pF Tan δ 0.33
%
C2 80 pF Tan δ 0.45
%
Nameplate with
marking example.
20
Distance to flat
surface e.g. tank or
core clamp
ABB AB
Components
SE-771 80 Ludvika, Sweden
Phone: +46 240 78 20 00
Fax:
+46 240 121 57
E-Mail: [email protected]
www.abb.com/electricalcomponents
© Copyright 2010 ABB, All rights reserved. 1ZSE 2750-102 en, Rev. 7, 2007-10-15
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