PROTECTION & CONTROL
Minimize Energy Let-Through —
Maximize Equipment Protection.
PROTECTION & CONTROL
Trans-Guard™ EXT
Current-Limiting Backup Fuse
For 12K–40K Ratings
For 100K Ratings
For 65K–80K Ratings
Trans-Guard EXT Current-Limiting Backup Fuse
™
Voltage Selection — Refer to Table 1. Each Trans-Guard™ EXT Current-Limiting Backup Fuse is suitable for use in both single-phase and threeIn addition to interrupting higher fault currents, the Trans-Guard™ EXT Current-Limiting
phase applications where the system voltage does not exceed the Maximum System Voltage listed. For single-phase applications on delta systems,
Backup Fuse serves the very important function of limiting the amount of energy
one fuse is needed in each line.
let-through to the source of the fault to a value below the withstand capability
Current-Rating Selection — Refer to Table 2. Each Trans-Guard™ EXT Current-Limiting Backup Fuse will coordinate with any link having a
of the equipment being protected.
rating no greater than that listed. For types of links not listed in Table 2, please contact Thomas & Betts for assistance. For more information
concerning how Trans-Guard™ EXT Current-Limiting Backup Fuses are coordinated, please consult Application Guide FS-10.
Hardware Selection — Many different hardware options are available. Some options vary depending on the size of the Trans-Guard™ EXT Current-
New and improved design offers you:
Limiting Backup Fuse required. Please refer to Ordering Information for available options.
•
Smaller size and lighter weight for easier handling
•
Lowest energy let-through in the industry
•
The most complete range of ratings available
Table 1
Nominal
Voltage
Rating
(kV)
8.3
Electrical Characteristics of Trans-Guard™ EXT Current-Limiting Backup Fuse
Rated
Maximum
Interrupting
Current (kA)
Peak
Arc
Voltage
(kV)
Minimum
Melt I2t
(A2sec)
Maximum
Total I2t
(A2sec)
12K
26
2,700
8,000
25K
26
11,000
29,000
40K
25
26,000
72,000
Current
Rating
Rated
Maximum
Voltage
(kV)
50
65K
Maximum
System
Voltage
(kV)
8.3
14.4
22
67,000
230,000
80K
22
156,000
580,000
100K
24
218,000
850,000
12K
47
2,700
9,000
49
11,000
34,000
40K
47
26,000
85,000
65K
44
67,000
230,000
25K
15.5
44
80K
17.2
50
27.6
15.5
24.9
100K
12K
25K
23.0
31
40K
23.0
65K
EXPULSION FUSE OPERATION
CURRENT-LIMITING FUSE OPERATION
Current
peak
Current
peak
Current
interruption
Current
interruption
Fuse Current
Fault Current
Energy Let-Through
34.5
50
80K
Table 2
Setting the Standard
in System Protection
44
156,000
580,000
46
204,000
730,000
62
2,700
10,000
60
11,000
37,000
62
26,000
88,000
65
67,000
220,000
63
123,000
360,000
Trans-Guard™ EXT Current-Limiting Backup Fuse/Expulsion Fuse Link Coordination
Trans-Guard EXT
Fuse Rating
Type K
Type T
Type N
Type S
Coordinates with links up through
Type H
Type D
Type X
Type QA
Type KS
12K
12
8
20
5
8
3
2.5
15
3
25K
25
15
30
7
8
20
10
30
7
40K
40
20
50
15
8
20
15
50
15
65K
65
30
60
25
8
20
15
75
15
80K
80
50
85
40
8
20
15
100
15
100K
100
65
85
50
8
20
15
125
15
Thomas & Betts Corporation
Utility Products Group
8155 T&B Blvd.
Memphis, TN 38125
P: 800.888.0211
F: 800.888.0690
©2008 Thomas & Betts Corporation. All rights reserved. Printed in the USA.
PB-PC-EXT-0208
Trans-Guard™ EXT
Current-Limiting
Backup Fuse
PROTECTION & CONTROL
Application
Trans-Guard™ EXT Current-Limiting Backup Fuse for 12K–40K Ratings
Trans-Guard™ EXT Current-Limiting Backup Fuse for 65K–80K Ratings
Designed to enhance protection on overhead distribution systems, the Trans-Guard™ EXT Current-Limiting Backup Fuse both significantly reduces
energy let-through during a fault and offers very high interrupting capability to provide state-of-the-art protection against today’s ever increasing
available fault currents.
A
A
Type of Installations
SOURCE SIDE CUTOUT
INSTALLATION
BUSHING MOUNT
INSTALLATION
B
B
Ordering Information
for 12K–40K Ratings
Current Rating
Dimension “B”
(inches)
Weight
(lbs)
Base Catalog Number*
12K
1.5
5.2
1.0
HTDE33 (X) 065
25K
1.5
7.1
1.1
HTDE33 (X) 080
HTDE23 (X) 040
40K
2.2
6.3
2.2
HTDE34 (X) 065
HTDE24 (X) 012
12K
1.5
8.6
1.3
HTDE34 (X) 080
HTDE23 (X) 012
HTDE23 (X) 025
HTDE24 (X) 025
8.3
15.5
HTDE24 (X) 040
HTDE25 (X) 012
HTDE25 (X) 025
NOTE: The Trans-Guard™ EXT Current-Limiting Backup Fuse
interrupts high-level currents and must be applied in series with
LOAD SIDE CUTOUT
INSTALLATION
HOT-LINE/BAIL
INSTALLATION
Ordering Information
Dimension “A”
(inches)
Base Catalog Number*
Nominal Voltage
Rating (kV)
23.0
HTDE25 (X) 040
25K
1.5
11.9
1.8
HTDE35 (X) 065
40K
2.2
10.4
3.3
HTDE35 (X) 080
12K
1.5
10.5
1.6
25K
2.2
13.4
4.0
40K
2.2
13.4
4.0
for 65K–80K Ratings
Nominal Voltage
Rating (kV)
Current Rating
Dimension “A”
(inches)
Dimension “B”
(inches)
Weight
(lbs)
3.3
9.9
7.5
3.3
15.5
10.5
3.3
18.3
12.5
65K
8.3
80K
65K
15.5
80K
65K
23.0
80K
*When ordering, replace the (X) in the Base Catalog Number with the appropriate hardware code from the chart below.
Hardware for 65K–80K Ratings
*When ordering, replace the (X) in the Base Catalog Number with the appropriate hardware code from the chart below.
another device capable of interrupting low- to mid-level currents.
2.0"
1.9"
2.2"
Hardware for 12K–40K Ratings
This is most commonly a cutout expulsion fuse. When properly
3.3"
coordinated, the Trans-Guard™ EXT Current-Limiting Backup Fuse
always allows sufficient let-through current to cause the cutout fuse
1.1"
to melt and drop open, making it easy to visually pinpoint where
1.1"
1.1"
or
1.5"
1.9"
the fault occurred.
1.1" for 1.5" dia. fuses
.29"
.29"
.46"
1.5" for 2.2" dia. fuses
Eyebolt
Knurled Stud
(Accepts #8 – 2/0)
Threaded Stud
Universal Adapter
(1⁄2" – 13 threads)
Rotatable through 180˚
.42"
Hardware Code
Features
Superior performance
Benefits/Descriptions
Eyebolt
Lowest total I2t let-throughs in the industry provide maximum protection for equipment by
minimizing energy let-through during a fault. Higher melt I t’s on smaller fuse ratings make
Knurled Stud
Parallel-Groove
(Accepts #8 – 2/0)
Spade
(Accepts #6 – 2/0)
2
fuses less susceptible to damage from current surges.
1st End Hardware
2nd End Hardware
1
Spade
Knurled Stud
5
Parallel-Groove
Knurled Stud
6
Parallel-Groove
Spade
8
Eyebolt
Knurled Stud
9
Universal Adapter
Spade
Extends outdoor life and includes machined brass endcaps and filament-wound epoxy,
C
Universal Adapter
Knurled Stud
centerless ground tubular bodies, ground and coated with oven-baked acrylic paint.
F
Eyebolt
Eyebolt
G
Parallel-Groove
Eyebolt
As high as 50kA symmetrical. (see Table 1)
Small physical size
Shorter, lighter weight design makes fuses easy to handle and install.
Integral pre-assembled hardware
Reduces installation time and likelihood of joint deterioration.
Broadest range of ratings available
Current-limiting action
Up to 100K at 8.3kV and 15.5kV; up to 80K at 23kV.
Improves power quality by reducing voltage dip time during a fault and reduces flame discharge
and noise associated with the operation of the series-connected cutout fuse.
Multiple hardware options
for 12K–40K Ratings
Hardware Code
(X)
High fault interrupting capability
Durable design
Hardware Code
Wide variety of mounting and connection options for greater flexibility in installation.
H
Eyebolt
Spade
J
Eyebolt
Universal Adapter
Z
Parallel-Groove
Universal Adapter
for 65K–80K Ratings
Hardware Code
(X)
1st End Hardware
2nd End Hardware
A
Threaded Stud
Threaded Stud
E
Eyebolt
Knurled Stud
F
Eyebolt
Eyebolt
U
Eyebolt
Universal Adapter
3.3"
Trans-Guard™ EXT Current-Limiting Backup Fuse for 100K Ratings
.29"
C
1.8"
Eyebolt
A
.46"
(Accepts #8 – 2/0)
Universal Adapter
Rotatable through 180˚
B
Ordering Information
for 100K Ratings
Nominal Voltage
Rating (kV)
Current Rating
HTDE23E100
8.3
100K
4.9
14.0
11.9
7.5
HTDE24E100
15.5
100K
4.9
19.4
17.5
10.5
Catalog Number
Dimension “A”
(inches)
Dimension “B”
(inches)
Dimension “C”
(inches)
Weight
(lbs)
PROTECTION & CONTROL
Application
Trans-Guard™ EXT Current-Limiting Backup Fuse for 12K–40K Ratings
Trans-Guard™ EXT Current-Limiting Backup Fuse for 65K–80K Ratings
Designed to enhance protection on overhead distribution systems, the Trans-Guard™ EXT Current-Limiting Backup Fuse both significantly reduces
energy let-through during a fault and offers very high interrupting capability to provide state-of-the-art protection against today’s ever increasing
available fault currents.
A
A
Type of Installations
SOURCE SIDE CUTOUT
INSTALLATION
BUSHING MOUNT
INSTALLATION
B
B
Ordering Information
for 12K–40K Ratings
Current Rating
Dimension “B”
(inches)
Weight
(lbs)
Base Catalog Number*
12K
1.5
5.2
1.0
HTDE33 (X) 065
25K
1.5
7.1
1.1
HTDE33 (X) 080
HTDE23 (X) 040
40K
2.2
6.3
2.2
HTDE34 (X) 065
HTDE24 (X) 012
12K
1.5
8.6
1.3
HTDE34 (X) 080
HTDE23 (X) 012
HTDE23 (X) 025
HTDE24 (X) 025
8.3
15.5
HTDE24 (X) 040
HTDE25 (X) 012
HTDE25 (X) 025
NOTE: The Trans-Guard™ EXT Current-Limiting Backup Fuse
interrupts high-level currents and must be applied in series with
LOAD SIDE CUTOUT
INSTALLATION
HOT-LINE/BAIL
INSTALLATION
Ordering Information
Dimension “A”
(inches)
Base Catalog Number*
Nominal Voltage
Rating (kV)
23.0
HTDE25 (X) 040
25K
1.5
11.9
1.8
HTDE35 (X) 065
40K
2.2
10.4
3.3
HTDE35 (X) 080
12K
1.5
10.5
1.6
25K
2.2
13.4
4.0
40K
2.2
13.4
4.0
for 65K–80K Ratings
Nominal Voltage
Rating (kV)
Current Rating
Dimension “A”
(inches)
Dimension “B”
(inches)
Weight
(lbs)
3.3
9.9
7.5
3.3
15.5
10.5
3.3
18.3
12.5
65K
8.3
80K
65K
15.5
80K
65K
23.0
80K
*When ordering, replace the (X) in the Base Catalog Number with the appropriate hardware code from the chart below.
Hardware for 65K–80K Ratings
*When ordering, replace the (X) in the Base Catalog Number with the appropriate hardware code from the chart below.
another device capable of interrupting low- to mid-level currents.
2.0"
1.9"
2.2"
Hardware for 12K–40K Ratings
This is most commonly a cutout expulsion fuse. When properly
3.3"
coordinated, the Trans-Guard™ EXT Current-Limiting Backup Fuse
always allows sufficient let-through current to cause the cutout fuse
1.1"
to melt and drop open, making it easy to visually pinpoint where
1.1"
1.1"
or
1.5"
1.9"
the fault occurred.
1.1" for 1.5" dia. fuses
.29"
.29"
.46"
1.5" for 2.2" dia. fuses
Eyebolt
Knurled Stud
(Accepts #8 – 2/0)
Threaded Stud
Universal Adapter
(1⁄2" – 13 threads)
Rotatable through 180˚
.42"
Hardware Code
Features
Superior performance
Benefits/Descriptions
Eyebolt
Lowest total I2t let-throughs in the industry provide maximum protection for equipment by
minimizing energy let-through during a fault. Higher melt I t’s on smaller fuse ratings make
Knurled Stud
Parallel-Groove
(Accepts #8 – 2/0)
Spade
(Accepts #6 – 2/0)
2
fuses less susceptible to damage from current surges.
1st End Hardware
2nd End Hardware
1
Spade
Knurled Stud
5
Parallel-Groove
Knurled Stud
6
Parallel-Groove
Spade
8
Eyebolt
Knurled Stud
9
Universal Adapter
Spade
Extends outdoor life and includes machined brass endcaps and filament-wound epoxy,
C
Universal Adapter
Knurled Stud
centerless ground tubular bodies, ground and coated with oven-baked acrylic paint.
F
Eyebolt
Eyebolt
G
Parallel-Groove
Eyebolt
As high as 50kA symmetrical. (see Table 1)
Small physical size
Shorter, lighter weight design makes fuses easy to handle and install.
Integral pre-assembled hardware
Reduces installation time and likelihood of joint deterioration.
Broadest range of ratings available
Current-limiting action
Up to 100K at 8.3kV and 15.5kV; up to 80K at 23kV.
Improves power quality by reducing voltage dip time during a fault and reduces flame discharge
and noise associated with the operation of the series-connected cutout fuse.
Multiple hardware options
for 12K–40K Ratings
Hardware Code
(X)
High fault interrupting capability
Durable design
Hardware Code
Wide variety of mounting and connection options for greater flexibility in installation.
H
Eyebolt
Spade
J
Eyebolt
Universal Adapter
Z
Parallel-Groove
Universal Adapter
for 65K–80K Ratings
Hardware Code
(X)
1st End Hardware
2nd End Hardware
A
Threaded Stud
Threaded Stud
E
Eyebolt
Knurled Stud
F
Eyebolt
Eyebolt
U
Eyebolt
Universal Adapter
3.3"
Trans-Guard™ EXT Current-Limiting Backup Fuse for 100K Ratings
.29"
C
1.8"
Eyebolt
A
.46"
(Accepts #8 – 2/0)
Universal Adapter
Rotatable through 180˚
B
Ordering Information
for 100K Ratings
Nominal Voltage
Rating (kV)
Current Rating
HTDE23E100
8.3
100K
4.9
14.0
11.9
7.5
HTDE24E100
15.5
100K
4.9
19.4
17.5
10.5
Catalog Number
Dimension “A”
(inches)
Dimension “B”
(inches)
Dimension “C”
(inches)
Weight
(lbs)
PROTECTION & CONTROL
Application
Trans-Guard™ EXT Current-Limiting Backup Fuse for 12K–40K Ratings
Trans-Guard™ EXT Current-Limiting Backup Fuse for 65K–80K Ratings
Designed to enhance protection on overhead distribution systems, the Trans-Guard™ EXT Current-Limiting Backup Fuse both significantly reduces
energy let-through during a fault and offers very high interrupting capability to provide state-of-the-art protection against today’s ever increasing
available fault currents.
A
A
Type of Installations
SOURCE SIDE CUTOUT
INSTALLATION
BUSHING MOUNT
INSTALLATION
B
B
Ordering Information
for 12K–40K Ratings
Current Rating
Dimension “B”
(inches)
Weight
(lbs)
Base Catalog Number*
12K
1.5
5.2
1.0
HTDE33 (X) 065
25K
1.5
7.1
1.1
HTDE33 (X) 080
HTDE23 (X) 040
40K
2.2
6.3
2.2
HTDE34 (X) 065
HTDE24 (X) 012
12K
1.5
8.6
1.3
HTDE34 (X) 080
HTDE23 (X) 012
HTDE23 (X) 025
HTDE24 (X) 025
8.3
15.5
HTDE24 (X) 040
HTDE25 (X) 012
HTDE25 (X) 025
NOTE: The Trans-Guard™ EXT Current-Limiting Backup Fuse
interrupts high-level currents and must be applied in series with
LOAD SIDE CUTOUT
INSTALLATION
HOT-LINE/BAIL
INSTALLATION
Ordering Information
Dimension “A”
(inches)
Base Catalog Number*
Nominal Voltage
Rating (kV)
23.0
HTDE25 (X) 040
25K
1.5
11.9
1.8
HTDE35 (X) 065
40K
2.2
10.4
3.3
HTDE35 (X) 080
12K
1.5
10.5
1.6
25K
2.2
13.4
4.0
40K
2.2
13.4
4.0
for 65K–80K Ratings
Nominal Voltage
Rating (kV)
Current Rating
Dimension “A”
(inches)
Dimension “B”
(inches)
Weight
(lbs)
3.3
9.9
7.5
3.3
15.5
10.5
3.3
18.3
12.5
65K
8.3
80K
65K
15.5
80K
65K
23.0
80K
*When ordering, replace the (X) in the Base Catalog Number with the appropriate hardware code from the chart below.
Hardware for 65K–80K Ratings
*When ordering, replace the (X) in the Base Catalog Number with the appropriate hardware code from the chart below.
another device capable of interrupting low- to mid-level currents.
2.0"
1.9"
2.2"
Hardware for 12K–40K Ratings
This is most commonly a cutout expulsion fuse. When properly
3.3"
coordinated, the Trans-Guard™ EXT Current-Limiting Backup Fuse
always allows sufficient let-through current to cause the cutout fuse
1.1"
to melt and drop open, making it easy to visually pinpoint where
1.1"
1.1"
or
1.5"
1.9"
the fault occurred.
1.1" for 1.5" dia. fuses
.29"
.29"
.46"
1.5" for 2.2" dia. fuses
Eyebolt
Knurled Stud
(Accepts #8 – 2/0)
Threaded Stud
Universal Adapter
(1⁄2" – 13 threads)
Rotatable through 180˚
.42"
Hardware Code
Features
Superior performance
Benefits/Descriptions
Eyebolt
Lowest total I2t let-throughs in the industry provide maximum protection for equipment by
minimizing energy let-through during a fault. Higher melt I t’s on smaller fuse ratings make
Knurled Stud
Parallel-Groove
(Accepts #8 – 2/0)
Spade
(Accepts #6 – 2/0)
2
fuses less susceptible to damage from current surges.
1st End Hardware
2nd End Hardware
1
Spade
Knurled Stud
5
Parallel-Groove
Knurled Stud
6
Parallel-Groove
Spade
8
Eyebolt
Knurled Stud
9
Universal Adapter
Spade
Extends outdoor life and includes machined brass endcaps and filament-wound epoxy,
C
Universal Adapter
Knurled Stud
centerless ground tubular bodies, ground and coated with oven-baked acrylic paint.
F
Eyebolt
Eyebolt
G
Parallel-Groove
Eyebolt
As high as 50kA symmetrical. (see Table 1)
Small physical size
Shorter, lighter weight design makes fuses easy to handle and install.
Integral pre-assembled hardware
Reduces installation time and likelihood of joint deterioration.
Broadest range of ratings available
Current-limiting action
Up to 100K at 8.3kV and 15.5kV; up to 80K at 23kV.
Improves power quality by reducing voltage dip time during a fault and reduces flame discharge
and noise associated with the operation of the series-connected cutout fuse.
Multiple hardware options
for 12K–40K Ratings
Hardware Code
(X)
High fault interrupting capability
Durable design
Hardware Code
Wide variety of mounting and connection options for greater flexibility in installation.
H
Eyebolt
Spade
J
Eyebolt
Universal Adapter
Z
Parallel-Groove
Universal Adapter
for 65K–80K Ratings
Hardware Code
(X)
1st End Hardware
2nd End Hardware
A
Threaded Stud
Threaded Stud
E
Eyebolt
Knurled Stud
F
Eyebolt
Eyebolt
U
Eyebolt
Universal Adapter
3.3"
Trans-Guard™ EXT Current-Limiting Backup Fuse for 100K Ratings
.29"
C
1.8"
Eyebolt
A
.46"
(Accepts #8 – 2/0)
Universal Adapter
Rotatable through 180˚
B
Ordering Information
for 100K Ratings
Nominal Voltage
Rating (kV)
Current Rating
HTDE23E100
8.3
100K
4.9
14.0
11.9
7.5
HTDE24E100
15.5
100K
4.9
19.4
17.5
10.5
Catalog Number
Dimension “A”
(inches)
Dimension “B”
(inches)
Dimension “C”
(inches)
Weight
(lbs)
PROTECTION & CONTROL
Minimize Energy Let-Through —
Maximize Equipment Protection.
PROTECTION & CONTROL
Trans-Guard™ EXT
Current-Limiting Backup Fuse
For 12K–40K Ratings
For 100K Ratings
For 65K–80K Ratings
Trans-Guard EXT Current-Limiting Backup Fuse
™
Voltage Selection — Refer to Table 1. Each Trans-Guard™ EXT Current-Limiting Backup Fuse is suitable for use in both single-phase and threeIn addition to interrupting higher fault currents, the Trans-Guard™ EXT Current-Limiting
phase applications where the system voltage does not exceed the Maximum System Voltage listed. For single-phase applications on delta systems,
Backup Fuse serves the very important function of limiting the amount of energy
one fuse is needed in each line.
let-through to the source of the fault to a value below the withstand capability
Current-Rating Selection — Refer to Table 2. Each Trans-Guard™ EXT Current-Limiting Backup Fuse will coordinate with any link having a
of the equipment being protected.
rating no greater than that listed. For types of links not listed in Table 2, please contact Thomas & Betts for assistance. For more information
concerning how Trans-Guard™ EXT Current-Limiting Backup Fuses are coordinated, please consult Application Guide FS-10.
Hardware Selection — Many different hardware options are available. Some options vary depending on the size of the Trans-Guard™ EXT Current-
New and improved design offers you:
Limiting Backup Fuse required. Please refer to Ordering Information for available options.
•
Smaller size and lighter weight for easier handling
•
Lowest energy let-through in the industry
•
The most complete range of ratings available
Table 1
Nominal
Voltage
Rating
(kV)
8.3
Electrical Characteristics of Trans-Guard™ EXT Current-Limiting Backup Fuse
Rated
Maximum
Interrupting
Current (kA)
Peak
Arc
Voltage
(kV)
Minimum
Melt I2t
(A2sec)
Maximum
Total I2t
(A2sec)
12K
26
2,700
8,000
25K
26
11,000
29,000
40K
25
26,000
72,000
Current
Rating
Rated
Maximum
Voltage
(kV)
50
65K
Maximum
System
Voltage
(kV)
8.3
14.4
22
67,000
230,000
80K
22
156,000
580,000
100K
24
218,000
850,000
12K
47
2,700
9,000
49
11,000
34,000
40K
47
26,000
85,000
65K
44
67,000
230,000
25K
15.5
44
80K
17.2
50
27.6
15.5
24.9
100K
12K
25K
23.0
31
40K
23.0
65K
EXPULSION FUSE OPERATION
CURRENT-LIMITING FUSE OPERATION
Current
peak
Current
peak
Current
interruption
Current
interruption
Fuse Current
Fault Current
Energy Let-Through
34.5
50
80K
Table 2
Setting the Standard
in System Protection
44
156,000
580,000
46
204,000
730,000
62
2,700
10,000
60
11,000
37,000
62
26,000
88,000
65
67,000
220,000
63
123,000
360,000
Trans-Guard™ EXT Current-Limiting Backup Fuse/Expulsion Fuse Link Coordination
Trans-Guard EXT
Fuse Rating
Type K
Type T
Type N
Type S
Coordinates with links up through
Type H
Type D
Type X
Type QA
Type KS
12K
12
8
20
5
8
3
2.5
15
3
25K
25
15
30
7
8
20
10
30
7
40K
40
20
50
15
8
20
15
50
15
65K
65
30
60
25
8
20
15
75
15
80K
80
50
85
40
8
20
15
100
15
100K
100
65
85
50
8
20
15
125
15
Thomas & Betts Corporation
Utility Products Group
8155 T&B Blvd.
Memphis, TN 38125
P: 800.888.0211
F: 800.888.0690
©2008 Thomas & Betts Corporation. All rights reserved. Printed in the USA.
PB-PC-EXT-0208
Trans-Guard™ EXT
Current-Limiting
Backup Fuse
PROTECTION & CONTROL
Minimize Energy Let-Through —
Maximize Equipment Protection.
PROTECTION & CONTROL
Trans-Guard™ EXT
Current-Limiting Backup Fuse
For 12K–40K Ratings
For 100K Ratings
For 65K–80K Ratings
Trans-Guard EXT Current-Limiting Backup Fuse
™
Voltage Selection — Refer to Table 1. Each Trans-Guard™ EXT Current-Limiting Backup Fuse is suitable for use in both single-phase and threeIn addition to interrupting higher fault currents, the Trans-Guard™ EXT Current-Limiting
phase applications where the system voltage does not exceed the Maximum System Voltage listed. For single-phase applications on delta systems,
Backup Fuse serves the very important function of limiting the amount of energy
one fuse is needed in each line.
let-through to the source of the fault to a value below the withstand capability
Current-Rating Selection — Refer to Table 2. Each Trans-Guard™ EXT Current-Limiting Backup Fuse will coordinate with any link having a
of the equipment being protected.
rating no greater than that listed. For types of links not listed in Table 2, please contact Thomas & Betts for assistance. For more information
concerning how Trans-Guard™ EXT Current-Limiting Backup Fuses are coordinated, please consult Application Guide FS-10.
Hardware Selection — Many different hardware options are available. Some options vary depending on the size of the Trans-Guard™ EXT Current-
New and improved design offers you:
Limiting Backup Fuse required. Please refer to Ordering Information for available options.
•
Smaller size and lighter weight for easier handling
•
Lowest energy let-through in the industry
•
The most complete range of ratings available
Table 1
Nominal
Voltage
Rating
(kV)
8.3
Electrical Characteristics of Trans-Guard™ EXT Current-Limiting Backup Fuse
Rated
Maximum
Interrupting
Current (kA)
Peak
Arc
Voltage
(kV)
Minimum
Melt I2t
(A2sec)
Maximum
Total I2t
(A2sec)
12K
26
2,700
8,000
25K
26
11,000
29,000
40K
25
26,000
72,000
Current
Rating
Rated
Maximum
Voltage
(kV)
50
65K
Maximum
System
Voltage
(kV)
8.3
14.4
22
67,000
230,000
80K
22
156,000
580,000
100K
24
218,000
850,000
12K
47
2,700
9,000
49
11,000
34,000
40K
47
26,000
85,000
65K
44
67,000
230,000
25K
15.5
44
80K
17.2
50
27.6
15.5
24.9
100K
12K
25K
23.0
31
40K
23.0
65K
EXPULSION FUSE OPERATION
CURRENT-LIMITING FUSE OPERATION
Current
peak
Current
peak
Current
interruption
Current
interruption
Fuse Current
Fault Current
Energy Let-Through
34.5
50
80K
Table 2
Setting the Standard
in System Protection
44
156,000
580,000
46
204,000
730,000
62
2,700
10,000
60
11,000
37,000
62
26,000
88,000
65
67,000
220,000
63
123,000
360,000
Trans-Guard™ EXT Current-Limiting Backup Fuse/Expulsion Fuse Link Coordination
Trans-Guard EXT
Fuse Rating
Type K
Type T
Type N
Type S
Coordinates with links up through
Type H
Type D
Type X
Type QA
Type KS
12K
12
8
20
5
8
3
2.5
15
3
25K
25
15
30
7
8
20
10
30
7
40K
40
20
50
15
8
20
15
50
15
65K
65
30
60
25
8
20
15
75
15
80K
80
50
85
40
8
20
15
100
15
100K
100
65
85
50
8
20
15
125
15
Thomas & Betts Corporation
Utility Products Group
8155 T&B Blvd.
Memphis, TN 38125
P: 800.888.0211
F: 800.888.0690
©2008 Thomas & Betts Corporation. All rights reserved. Printed in the USA.
PB-PC-EXT-0208
Trans-Guard™ EXT
Current-Limiting
Backup Fuse