High Voltage Fuse Technology
For the protection of equipment operating above 1000 volts AC
Current Limiting
Current limiting HV fuse links split into three
internationally recognised types:
back-up
(or
partial
range)
fuse links, which will interrupt any current
from their rated breaking capacity down to a minimum
breaking current specified by the manufacturer; and
general purpose
fuse links, which will interrupt all
currents from rated breaking capacity down to a
current that will melt the elements within one hour.
A third type is the full range fuse. This term applies
to fuse links that can interrupt any current below
the rated breaking capacity that melts the fuse
elements satisfactorily.
Current limiting
back-up fuse links
are the closest in
construction to LV cartridge types. However, a longer strip
element with many more restrictions is necessary to
produce the large number of series arcs needed to
interrupt a high voltage. Fuse manufacturers achieve
this by coiling the element around a ceramic core with a
star shaped cross section. In this way, a 1m long element
can be fitted into a 250mm long fuse body. If the adjacent
coils are too close, there will be a flashover between
them and this sets a practical limit on how long an
element can be crammed into a particular cartridge, and
how many elements can be used in parallel.
Cross Section
End cap
Porcelain barrel
Star core
Moisture tight seal
Star core
Silver ceramic
point contact
Striker coil
Granular
Quartz
Fuse elements
Porcelain barrel
Fuse elements
Granular Quartz
Striker coil
Expelled striker
Like an LV cartridge fuse link, an HV fuse link of this
type has a ceramic body.
Many HV current limiting fuse links are also fitted with
a
striker mechanism.
This not only provides the user
with a visual indication that the fuse link has operated,
but can also be used to operate other switchgear. In
this way, a fuse on a single phase system can cut off all
three phases if a fault occurs.
Striker mechanisms are driven by explosive charges or
compressed springs. Both are triggered by a thin fuse
wire running the length of the fuse, usually through the
centre of the star shaped core. The wire is connected
in parallel with the elements, so a current flows
through it when the elements melt. The current
heats up the wire and detonates the explosive
charge, or melts the wire andreleases the spring,
pushing the striker pin out of the fuse link’s end
cap. A lock washer mechanism makes it impossible
to push the pin back into the fuse body.
There are several variations on this design for specific
applications. For example, the elements in three-
phase motor protection fuse links are corrugated to
withstand the cyclical mechanical stresses induced
by the high starting and stopping currents drawn
by the motor.
1
For
more information visit our website
www.bussmann.com
High Voltage Fuse Technology
For the protection of equipment operating above 1000 volts AC
Non- Current Limiting
Essentially, non-current limiting fuse links have short
elements and incorporate some means of lengthening
the arc after the element melts, extinguishing the arc
and preventing re-ignition. There are two distinct types:
expulsion fuse links
and
liquid fuse links.
Expulsion fuses are an effective way of protecting
overhead distribution lines and transformers. They are
designed for outdoor use only and comprise a tin or
copper fuse element in series with a flexible braid in a
tube. The tube forms one side of a triangle, with a
latched connection at the top and a hinge at the
bottom. The braid emerges from one end of the fuse
link and is held in tension by a spring.
When the element melts, the braid is no longer under
tension, the latch is released and the fuse swings
downwards under gravity, breaking the circuit. As the
fuse swings downwards, the arc is lengthened,
extinguished and prevented from restriking.
Liquid fuse links
are based on early non-current
limiting fuse links which use liquids to quench the arc.
The fuse element is anchored to the top ferrule of a
glass tube filled with a quenching liquid - usually a
hydrocarbon. The rest of the tube is filled with a
spring that holds the element - or a strain wire in very
high voltage fuse links - in tension.
When the element melts, the spring pulls the two
parts of the element apart, extending the arc and
quenching it in the liquid.
M- effect
Bussmann high voltage fuse links include M-effect as a design feature to enhance performance. M-effect
(named after its discoverer, Prof. Metcalf, in the late 1930s) consists of applying overlay spots of special low
melting alloy onto the fuse element strips. Its effect is to ensure that the fuse link runs cooler in service and
that the maximum temperature reached during fuse operation is kept down to a modest 160 deg. C
(compared with 300 - 400 deg C for fuse links which do not employ this feature).
M-effect has been in widespread use in both low voltage and high voltage fuse links of British design for
many years and is now coming into use in many other countries. Cooler running M-effect fuse links have
longer service life since lower surface temperature on the elements ensures against long term embrittlement
of the material. The M-effect spots are stable and have been proved by many tests to remain inert for
periods of 30 years or more.
The low maximum operating temperature of M-effect fuse links ensures safe operation of Back-up types in
striker tripped switchgear under low fault conditions. Whereas non M-effect types are known to have a risk
of body fracture because of their much higher body temperature under such conditions. The low maximum
operating temperature also ensures against damage to heat sensitive fuse enclosures such as cast resin
fuse pods.
In short, M-effect fuse links are safer, give better protection and are longer lasting than alternative designs
which do not employ this valuable feature.
For
more information visit our website
www.bussmann.com
2
DIN - Fuse Links
Fuse Links comply with DIN dimensional
standard DIN43625.
‘F’ range, high performance full range fuse link.
‘S’ range, high performance back-up fuse
link, with striker tripping.
‘A’ range, including high current rating
back-up fuse link.
Comply with IEC 60282-1 and VDE 0670 part 4.
Wide variety of ratings, 3.6 kV to 36 kV.
Versions suitable for indoor and outdoor use.
Motor circuit fuse link option.
Bussmann DIN ‘S’ Fuse Links
The time current characteristics of the ‘S’ range is optimised to ensure improved discrimination with upstream devices
and to give fast clearance of earth faults in the secondary terminal zones. The breaking performance with low over
currents is adequate to cater for all normal distribution applications, where low voltage fuse links on the secondary side
take care of low overload faults, leaving the high voltage fuse links to clear major faults ahead of LV protection. The fuse
links are suitable for use even where there is no secondary LV protection, provided that they are used in fuse switches
fitted with instantaneous striker tripping.
Bussmann DIN ‘F’ Fuse Links
The ‘F’ range fuse links have ‘full range’ clearing capability. Bussmann ‘F’ types are designed to clear all overloads right
down to fuse’s rated current in accordance with latest IEC 282-1 requirements. They are thus suitable for use as a sole
form of protection. ‘F’ range time current characteristics are especially advantageous for transformer protection
applications.
Bussmann DIN ‘A’ Fuse Links
This earlier, well proven design, has values of minimum breaking current between the ‘S’ and ‘F’ range including higher
current ratings.
3
For
more information visit our website
www.bussmann.com
DIN - Fuse Links
Selection Tables
Table of ratings for ‘S’ range 7.2 - 36kV to DIN dimensions
Voltage
Rating
Part Number
Un
kV
Current
Rating
Breaking
Capacity
Minimum
Breaking Current
Cold resistance and watts loss
in free air at rated current
Joule
Intergral
(I
2
t)
A
2
s
Length
Diameter
Weight
ø
In
A
I1
kA
I3
A
m
Ω
W
Minimum
Pre-Arcing
Maximum
Total Clearing
mm
mm
kg
7.2SDLSJ6.3
7.2SDLSJ10
7.2SDLSJ16
7.2SDLSJ20
7.2SDLSJ25
7.2SDLSJ31.5
7.2SDLSJ40
7.2SDLSJ50
7.2SDLSJ63
7.2SFLSJ80
7.2SFLSJ100
7.2SFLSJ125
7.2SFLSJ160
12SDLSJ6.3
12SDLSJ10
12SDLSJ16
12SDLSJ20
12SDLSJ25
12SDLSJ31.5
12SDLSJ40
12SDLSJ50
12SDLSJ63
12SFLSJ50
12SFLSJ63
12SFLSJ80
12SFLSJ100
12SKLSJ125
12SXLEJ160
12SXLEJ200
15.5SFMSJ100
15.5SKMSJ125
17.5SDLSJ6.3
17.5SDLSJ10
17.5SDLSJ16
17.5SDLSJ20
17.5SDLSJ25
17.5SDLSJ31.5
17.5SDLSJ40
17.5SFLSJ31.5
17.5SFLSJ40
17.5SFLSJ50
17.5SDMSJ6.3
17.5SDMSJ10
17.5SDMSJ16
17.5SDMSJ20
17.5SDMSJ25
17.5SDMSJ31.5
17.5SDMSJ40
17.5SFMSJ50
17.5SFMSJ63
17.5SFMSJ80
24SDMSJ6.3
24SDMSJ10
24SDMSJ16
24SDMSJ20
24SDMSJ25
24SDMSJ31.5
24SDMSJ40
24SFMSJ40
24SFMSJ50
24SFMSJ63
24SFMSJ71
24SHMEJ80
24SHMEJ100
24SKMEJ125
24SXMEJ160
36SDQSJ3.15
36SDQSJ6.3
36SDQSJ10
36SDQSJ16
36SDQSJ20
36SDQSJ25
36SFQSJ31.5
36SFQSJ40
36SFQSJ50
36SXQEJ63
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
15.5
15.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
17.5
24
24
24
24
24
24
24
24
24
24
24
24
24
24
24
36
36
36
36
36
36
36
36
36
36
6.3
10
16
20
25
31.5
40
50
63
80
100
125
160
6.3
10
16
20
25
31.5
40
50
63
50
63
80
100
125
160
200
100
125
6.3
10
16
20
25
31.5
40
31.5
40
50
6.3
10
16
20
25
31.5
40
50
63
80
6.3
10
16
20
25
31.5
40
40
50
63
71
80
100
125
160
3.15
6.3
10
16
20
25
31.5
40
50
63
40
40
40
40
40
40
40
40
40
40
40
40
40
50
50
50
50
50
50
50
50
50
50
50
50
50
50
63
63
25
25
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35
35
35
50
50
50
50
50
50
50
50
50
50
50
63
63
63
63
20
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
20
20
31
49
49
80
100
114
143
180
264
338
375
525
20
28
35
72
90
90
128
196
275
160
227
256
446
870
500
610
707
990
23
19
59
80
100
118
148
118
132
225
16
27
57
80
100
100
143
180
240
270
19
28
47
80
84
105
140
119
225
306
350
300
350
420
320
-
23
35
70
98
112
116
178
255
280
205
99.7
65.1
48.9
32.6
26.0
16.0
12.9
8.14
6.01
4.65
3.60
2.73
285
143
81.4
54.6
43.7
32.8
21.6
15.1
12.1
17.1
12.1
8.97
5.61
4.60
4.30
3.80
8.23
5.61
313
185
104
69.2
55.4
41.4
31.1
30.3
21.9
17.3
509
215
112
79.8
63.8
47.9
31.6
25.0
17.8
13.1
489
287
165
79.3
62.0
46.5
34.0
38.0
27.1
21.6
17.7
20.5
18.0
16.7
14.0
-
684
402
165
117
98.0
73.4
52.4
36.8
35.0
11
19
23
27
28
36
36
46
45
54
64
79
97
14
18
26
28
35
43
49
59
75
61
69
88
83
115
200
330
119
126
15
23
34
38
48
58
76
37
51
62
26
28
37
38
52
61
66
88
102
128
24
35
60
38
49
56
79
85
96
128
134
250
350
171
279
-
34
44
52
62
85
96
116
133
271
4.8X10
1
2.5X10
2
5.5X10
2
9.7X10
2
5.7X10
2
8.9X10
2
2.0X10
2
3.2X10
2
8.0X10
2
5.0X10
3
9.1X10
3
1.5X10
4
3.0X10
4
7.0X10
1
3.1X10
2
9.8X10
2
5.7X10
2
8.9X10
2
1.6X10
3
3.2X10
3
1.3X10
3
2.3X10
3
5.2X10
3
1.0X10
4
1.9X10
4
1.4X10
4
2.8X10
4
1.1X10
5
1.5X10
5
1.2X10
4
2.4X10
4
4.8X10
1
2.8X10
2
2.9X10
2
5.7X10
2
8.9X10
2
5.1X10
2
8.0X10
2
2.6X10
3
5.1X10
3
8.1X10
3
4.8X10
1
3.1X10
2
2.9X10
2
5.7X10
2
8.9X10
2
1.6X10
3
3.2X10
3
5.2X10
3
1.0X10
4
1.9X10
4
8.1X10
1
3.1X10
2
9.8X10
2
8.1X10
2
1.3X10
3
2.1X10
3
3.2X10
3
5.1X10
3
8.1X10
3
3.8X10
3
5.0X10
3
1.7X10
4
2.8X10
4
2.4X10
4
4.4X10
4
-
1.0X10
2
3.1X10
2
4.6X10
2
8.9X10
2
1.2X10
3
2.1X10
3
4.1X10
3
8.3X10
3
1.1X10
4
6.5X10
2
2.7X10
3
8.2X10
3
1.1X10
4
8.0X10
3
1.0X10
4
2.2X10
4
3.2X10
4
7.5X10
4
6.5X10
4
1.1X10
5
1.7X10
5
3.1X10
5
6.5X10
2
2.7X10
3
8.6X10
3
5.1X10
3
8.1X10
4
1.5X10
4
2.7X10
4
3.2X10
4
5.7X10
4
4.1X10
4
8.8X10
4
1.5X10
5
2.2X10
5
2.3X10
5
5.0X10
5
6.5X10
5
1.4X10
5
2.2X10
5
6.1X10
2
4.0X10
3
2.0X10
3
4.4X10
3
6.6X10
3
1.1X10
4
1.8X10
4
1.9X10
4
3.8X10
4
6.0X10
4
6.0X10
2
3.8X10
3
1.2X10
4
6.7X10
3
1.1X10
4
2.0X10
4
3.6X10
4
5.5X10
4
1.2X10
5
1.9X10
5
1.3X10
3
5.5X10
3
1.5X10
4
1.1X10
4
2.0X10
4
2.9X10
4
4.4X10
4
6.9X10
4
9.0X10
4
5.0X10
4
6.6X10
4
8.4X10
4
9.3X10
4
8.7X10
4
1.7X10
5
-
1.2X10
3
3.6X10
3
5.1X10
3
8.2X10
4
1.5X10
4
2.3X10
4
3.9X10
4
8.1X10
4
6.2X10
4
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
292
442
442
292
292
292
292
292
292
292
292
292
292
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
442
537
537
537
537
537
537
537
537
537
537
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
76.2
76.2
76.2
76.2
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
76.2
76.2
76.2
76.2
76.2
88
88
76.2
76.2
50.8
50.8
50.8
50.8
50.8
50.8
50.8
76.2
76.2
76.2
50.8
50.8
50.8
50.8
50.8
50.8
50.8
76.2
76.2
76.2
50.8
50.8
50.8
50.8
50.8
50.8
50.8
76.2
76.2
76.2
76.2
64
64
78
88
50.8
50.8
50.8
50.8
50.8
50.8
76.2
76.2
76.2
88
1.63
1.63
1.63
1.63
1.63
1.63
1.63
1.63
1.63
3.1
3.1
3.1
3.1
1.63
1.63
1.63
1.63
1.63
1.63
1.63
1.63
1.63
3.1
3.1
3.1
3.1
3.1
3.7
3.7
4.5
4.5
1.63
1.63
1.63
1.63
1.63
1.63
1.63
3.1
3.1
3.1
2.2
2.2
2.2
2.2
2.2
2.2
2.2
4.5
4.5
4.5
2.2
2.2
2.2
2.2
2.2
2.2
2.2
4.5
4.5
4.5
4.5
3.1
3.1
3.7
4.2
2.9
2.9
2.9
2.9
2.9
2.9
6.0
6.0
6.0
6.5
For
more information visit our website
www.bussmann.com
Rating at 64%
4
DIN - Fuse Links
Selection Tables
Table of ratings for ‘F’ range 12 - 24kV to DIN dimensions
Voltage
Rating
Part Number
Un
kV
Current
Rating
Breaking
Capacity
Minimum
Breaking Current
Cold resistance and watts loss
in free air at rated current
Joule
Intergral
(I
2
t)
A
2
s
Length
Diameter
Weight
ø
In
A
I1
kA
I3
A
m
Ω
W
Minimum
Pre-Arcing
Maximum
Total Clearing
mm
mm
kg
12FDLSJ6.3
12FDLSJ10
12FDLSJ16
12FDLSJ20
12FDLSJ25
12FDLSJ31.5
12FFLSJ40
12FFLSJ50
12FFLSJ63
12FXLSJ80
12FXLSJ100
24FDMSJ6.3
24FDMSJ10
24FDMSJ16
24FDMSJ20
24FDMSJ25
24FDMSJ31.5
24FFMSJ25
24FFMSJ31.5
24FFMSJ40
24FFMSJ45
12
12
12
12
12
12
12
12
12
12
12
24
24
24
24
24
24
24
24
24
24
6.3
10
16
20
25
31.5
40
50
63
80
100
6.3
10
16
20
25
31.5
25
31.5
40
45
50
50
50
50
50
50
50
50
50
50
50
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
35.5
6.3
10
16
20
25
31.5
40
50
63
80
100
6.3
10
16
20
25
31.5
25
31.5
40
45
208
116
55.4
39.6
31.2
26.4
19.7
14.8
12.4
7.94
5.64
437
218
118
82.2
54.7
48.6
58.6
48.8
38.4
31.4
10
15
17
20
26
36
42
51
72
72
82
21
29
39
43
48
71
47
70
85
92
6.9X10
1
2.2X10
2
8.8X10
2
1.7X10
3
2.8X10
3
2.6X10
3
3.8X10
3
6.8X10
3
5.1X10
3
2.2X10
4
4.2X10
4
6.8X10
1
2.7X10
2
8.2X10
2
1.6X10
3
3.4X10
3
3.2X10
3
3.4X10
3
4.7X10
3
7.6X10
3
7.2X10
3
6.3X10
2
2.1X10
3
3.9X10
3
7.6X10
3
1.3X10
4
1.3X10
4
3.8X10
4
5.6X10
4
5.4X10
4
1.1X10
5
2.0X10
5
5.4X10
2
2.1X10
3
2.7X10
3
5.1X10
3
1.2X10
4
1.2X10
4
1.1X10
4
1.5X10
4
2.5X10
4
3.0X10
4
292
292
292
292
292
292
292
292
292
292
292
442
442
442
442
442
442
442
442
442
442
50.8
50.8
50.8
50.8
25.8
50.8
76.2
76.2
76.2
88
88
50.8
50.8
50.8
50.8
50.8
50.8
76.2
76.2
76.2
76.2
1.63
1.63
1.63
1.63
1.63
1.63
3.16
3.16
3.16
4
4
2.2
2.2
2.2
2.2
2.2
2.2
4.5
4.5
4.5
4.5
Table of ratings for ‘A’ range 3.6 - 24kV to DIN dimensions
Voltage
Rating
Part Number
Un
kV
Current
Rating
Breaking
Capacity
Minimum
Breaking Current
Cold resistance and watts loss
in free air at rated current
Joule
Intergral
(I
2
t)
A
2
s
Length
Diameter
Weight
ø
In
A
I1
kA
I3
A
m
Ω
W
Minimum
Pre-Arcing
Maximum
Total Clearing
mm
mm
kg
3.6ADOSJ6.3
3.6ADOSJ10
3.6ADOSJ16
3.6ADOSJ20
3.6ADOSJ25
3.6ADOSJ31.5
3.6ADOSJ40
3.6ADLSJ6.3
3.6ADLSJ10
3.6ADLSJ16
3.6ADLSJ20
3.6ADLSJ25
3.6ADLSJ31.5
3.6ADLSJ40
12AILSJ100
17.5AILSJ40
17.5AILSJ50
17.5AILSJ63
17.5AIMSJ100
24AFMSJ50
24AFMSJ63
24AIMSJ71
3.6
3.6
3.6
3.6
3.6
3.6
3.6
3.6
3.6
3.6
3.6
3.6
3.6
3.6
12
17.5
17.5
17.5
17.5
24
24
24
6.3
10
16
20
25
31.5
40
6.3
10
16
20
25
31.5
40
100
40
50
63
100
50
63
71
40
40
40
40
40
40
40
40
40
40
40
40
40
40
31.5
25
25
25
25
20
20
20
13
31
49
49
106
106
106
13
13
20
31
106
106
106
176
78
98
156
176
137
125
176
158
79.2
50.8
38.1
28.9
19.2
11.6
158
95.6
63.3
45.9
28.7
19.1
11.4
5.03
26.3
21.1
12.3
7.33
29.5
23.6
15.1
9
11
18
21
25
26
26
9
13
22
25
25
26
25
70
58
73
68
102
102
130
106
4.5X10
1
2.3X10
2
5.5X10
2
9.8X10
2
1.3X10
2
2.9X10
2
8.0X10
2
4.5X10
1
1.3X10
2
3.0X10
2
6.3X10
2
1.3X10
2
2.9X10
2
8.0X10
2
1.4X10
4
1.3X10
2.0X10
3
5.0X10
3
1.4X10
4
1.8X10
3.2X10
3
6.3X10
3
3
3
1.9X10
2
9.7X10
2
2.4X10
3
4.2X10
3
1.2X10
3
2.7X10
3
7.5X10
3
1.9X10
2
5.4X10
2
1.3X10
3
2.7X10
3
1.2X10
3
2.7X10
3
7.5X10
3
2.0X10
5
1.8X10
2.7X10
4
7.0X10
4
2.0X10
5
2.9X10
4.5X10
4
8.5X10
4
4
4
192
192
192
192
192
192
192
292
292
292
292
292
292
292
292
292
292
292
442
442
442
442
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
50.8
76.2
76.2
76.2
76.2
76.2
76.2
76.2
76.2
1.1
1.1
1.1
1.1
1.1
1.1
1.1
1.63
1.63
1.63
1.63
1.63
1.63
1.63
3.3
3.3
3.3
3.3
4.5
4.5
4.5
4.5
Notes
a)
b)
17.5kV fuse links in 10/12 dimensions are offered, since some
switchgear in the 10/12 series is suitable for use at higher voltages.
Fuse links listed are normally for indoor use but versions suitable
for outdoor use are olso available in the same ratings and
dimensions. For outdoor versions of the ‘S’ range, replace the ‘S’
with a ‘T’ when ordering - for example ‘TDLSJ’
c)
* All the fuse link code references listed in the proceeding tables
are for striker fitted versions, for non-striker versions please
replace the letter ‘S’ with the letter ‘N’ in the code - for example
‘SDLNJ’. For further information on our parts referencing system,
please refer to section 10 of this catalogue.
5
For
more information visit our website
www.bussmann.com