E-rated medium voltage fuses, Powr-gard, Fuses—medium voltage – Littelfuse 700-xxx Series User Manual
Page 4: Current-limiting description, Characteristics, Options, Dimensions, Rated
© JUNE 2011 Littelfuse POWR-GARD Products
www.littelfuse.com
POWR-GARD
®
Fuses—Medium Voltage
4
E-RATED MEDIUM VOLTAGE FUSES
Current-Limiting
Description
E-rated fuses have time current characteristics designed to
provide current-limiting protection for power transformers,
potential transformers, power centers, feeder centers, and unit
sub stations. When properly applied, they can protect against
high and low fault currents.
NEMA Standards for E-rated medium voltage fuses require that
fuses rated 100E or less open within 300 seconds
(5 minutes) when subjected to an RMS value of 200-240% of
the fuse continuous current rating; and fuses with an
E rating larger than 100E must open within 600 seconds
(10 minutes) when subjected to an RMS current of 220-240%
of the fuse’s continuous current rating. These values establish
one point on the time-current curve.
Application Note
Since these fuses are used for the protection of general
purpose circuits which may contain transformers, motors, and
other equipment producing in-rush and/or overload currents,
fuses should generally be rated at 140% of the normal full load
current, and circuits should be analyzed
to ensure that system load currents will not exceed the current
rating of the fuse.
3"DIA
Dim.A
Clip
Center
6.38"
Dim.B
9.75"
A
D
DD
DDD
Figure 4
Figure 5
Figure 6
Characteristics
Voltage Ratings:
2,750 V – 38,000 V
Current Range:
10E – 600E
Options
• Hermetically sealed for use in hazardous locations
(add “S” suffix to part number)
• Clip-lock (CL) and bolt-in styles available.
E
RATED
SySTEM/CATALOG
NUMBER
SIzE
DIM. A (INChES)
DIM. B (INChES)
MAx INTERRUPTING
RATING RMS (ASyM)
FIGURE
NUMBER
2.75 M
Ax. KV
10E1C2.75
10E
7"
10.875"
80,000
4
15E1C2.75
15E
7"
10.875"
80,000
4
20E1C2.75
20E
7"
10.875"
80,000
4
25E1C2.75
25E
7"
10.875"
80,000
4
30E1C2.75
30E
7"
10.875"
80,000
4
40E1C2.75
40E
7"
10.875"
80,000
4
50E1C2.75
50E
7"
10.875"
80,000
4
65E1C2.75
65E
7"
10.875"
80,000
4
80E1C2.75
80E
7"
10.875"
80,000
4
100E-1C2.75
100E
7"
10.875"
80,000
4
125E1C2.75
125E
7"
10.875"
80,000
4
150E1C2.75
150E
7"
10.875"
80,000
4
200E1C2.75
200E
7"
10.875"
80,000
4
125E2C2.75
125E
7"
10.875"
80,000
5
150E2C2.75
150E
7"
10.875"
80,000
5
200E2C2.75
200E
7"
10.875"
80,000
5
225E2C2.75
225E
7"
10.875"
80,000
5
250E2C2.75
250E
7"
10.875"
80,000
5
300E2C2.75
300E
7"
10.875"
80,000
5
350E2C2.75
350E
7"
10.875"
80,000
5
400E2C2.75
400E
7"
10.875"
80,000
5
450E2C2.75
450E
7"
10.875"
80,000
5
Dimensions