®
Fuses — MediumVoltage
POWR-GARD Fuses—MediumVoltage
E-RATED POTENTIAL TRANSFORMER FUSES
Current-Limiting
Characteristics
Description
Potential Transformer (PT) fuses are current-limiting fuses with
high interrupting ratings designed for the protection of potential
transformers.
Voltage Ratings:
Current Range:
625 VAC – 25,800 VAC
1/2E – 10E
Application Note
Dimensions
When applying fuses for the protection of transformers,
the magnetizing current in-rush must be considered. The
characteristics of the in-rush, which can be matched with
a fuse time-current curve, should be available from the
transformer manufacturer.
B
A
SySTEM/CATALOG
NUMBER
DIMENSION A
DIAMETER DIMENSION B
(INChES)
MAx INTERRUPTING
RATING RMS (SyM)
E
SIzE
(INChES)
RATED
3E4PT6
5E4PT6
7E4PT6
10E4PT6
500E4PT2.4
1E4PT2.4
3E
5E
7E
10E
1/2E
1E
4.6”
4.6”
4.6”
4.6”
4.6”
4.6”
0.8125”
0.8125”
0.8125”
0.8125”
0.8125”
0.8125”
37,500
37,500
37,500
37,500
37,500
37,500
2E4PT2.4
2E
4.6”
0.8125”
37,500
1E6PT2.75
2E6PT2.75
3E6PT2.75
1E8PT2.75
2E8PT2.75
3E8PT2.75
1E
2E
3E
1E
2E
3E
7.4”
7.4”
7.4”
9.5”
9.5”
9.5”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
37,500
37,500
37,500
37,500
37,500
37,500
1E5PT4.8
1E
5.6”
0.8125”
50,000
2E5PT4.8
2E
5.6”
0.8125”
50,000
1/2E6PT5.5
1E6PT5.5
2E6PT5.5
3E6PT5.5
5E6PT5.5
1/2E8PT5.5
1E8PT5.5
2E8PT5.5
3E8PT5.5
5E8PT5.5
10E8PT5.5
1/2E8PT8.25
1E8PT8.25
2E8PT8.25
3E8PT8.25
1/2E11PT15.5
1E11PT15.5
2E11PT15.5
3E11PT15.5
3E16PT15.5
5E16PT15.5
1/2E
1E
2E
3E
5E
1/2E
1E
2E
3E
5E
10E
1/2E
1E
2E
3
1/2E
1E
2E
3E
3E
7.4”
7.4”
7.4”
7.4”
7.4”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
1.5625”
50,000
50,000
50,000
50,000
50,000
50,000
50,000
50,000
50,000
50,000
50,000
50,000
50,000
50,000
50,000
35,000
35,000
35,000
35,000
35,000
35,000
9.5”
9.5”
9.5”
9.5”
9.5”
9.5”
9.5”
9.5”
9.5”
9.5”
12.8”
12.8”
12.8”
12.8”
17.5”
17.5”
5E
1/2E16PT25.5
1/2E
17.5”
1.5625”
32,000
1E16PT25.5
1E
17.5”
1.5625”
32,000
9
www.littelfuse.com
© JUNE 2011 Littelfuse POWR-GARD Products