Littelfuse 279 Series User Manual
Radial lead fuses
© 2013 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 12/19/13
Radial Lead Fuses
MICRO™ > Very Fast-Acting > 272/273/274/278/279 Series
272/273/274/278/279 Series, MICRO™ Very Fast-Acting Fuse
Description
Developed originally for the U.S. Space Program,
MICRO™ fuse provides reliability in a compact design.
The MICRO™ fuse is available in plug–in or radial lead
styles and a complete range of ampere ratings from
1/500 to 5A to suit a wide variety of design needs.
Agency Approvals
Agency
Agency File Number
Ampere Range
E10480
2mA - 5A
LR 29862
2mA - 5A
QPL
FM02
2mA - 5A
Features
Electrical Characteristics
Applications
QPL
% of Ampere
Rating
Ampere Rating
Opening Time
100%
1/500–5
4 Hours, Min.
200%
1/500–3/10
5 Seconds, Max.
4/10-5
2 Seconds, Max.
Ampere
Rating
(A)
Amp Code
(for all
above
series)
max
Voltage
Rating
(V)
Interrupting
Rating
Nominal
Cold
Resistance
(Ohms)
Nominal
melting
I
2
t (A
2
sec)
Agency Approvals
QPL
.002
.002
125
10,000 amperes at
125 VAC/VDC.
2200
0.00000000845
X
X
X
.005
.005
125
280
0.00000000810
X
X
X
.010
.010
125
80.0
0.000000462
X
X
X
.015
.015
125
44.0
0.00000123
X
X
X
.031
.031
125
16.0
0.00000810
X
X
X
.050
.050
125
3.20
0.0000666
X
X
X
.062
.062
125
2.32
0.000115
X
X
X
.100
.100
125
1.25
0.000385
X
X
X
.125
.125
125
1.0
0.000691
X
X
X
.200
.200
125
2.30
0.00409
X
X
X
.250
.250
125
1.75
0.00640
X
X
X
.300
.300
125
1.25
0.00945
X
X
X
.400
.400
125
0.227
0.0251
X
X
X
.500
.500
125
0.167
0.0716
X
X
X
.600
.600
125
0.430
0.0411
X
X
X
.700
.700
125
0.324
0.0710
X
X
X
.750
.750
125
0.293
0.0900
X
X
X
.800
.800
125
0.271
0.113
X
X
X
1.00
001.
125
0.0880
0.0648
X
X
X
01.5
01.5
125
0.0578
0.160
X
X
X
2.00
002.
125
0.0425
0.300
X
X
X
3.00
003.
125
0.0275
0.759
X
X
X
4.00
004.
125
0.0202
1.38
X
X
X
5.00
005.
125
0.0156
2.21
X
X
X
Electrical Characteristics
• Military grade available
• High breaking capacity
• Clear cover option to view
fuse element status
• Available from very low
ampere of 2mA to 5A
• Plug-in with short or long
leads option
• Printed circuit boards
and similar equipment
• Electronic components