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Subminiature
Axial Lead and Cartridge Fuses
PICO
II
Very Fast-Acting Fuse 251/253
280
www.littelfuse.com
The PICO
II very fast-acting fuse is designed to meet an extensive array
of performance characteristics in a space-saving subminiature package.
ELECTRICAL CHARACTERISTICS:
% of Ampere
Ampere
Rating
Rating
100%
1/16–15
1/16–7
200%
10
12–15
Opening
Time
4 hours,
Min
imum
1 second,
Max
imum
3 seconds,
Max
imum
10 seconds,
Max
imum
AGENCY APPROVALS:
Recognized under the Components
Program of Underwriters Laboratories and Certified by CSA.
Approved by METI from 1 through 5 amperes.
AGENCY FILE NUMBERS:
UL E10480, CSA LR 29862.
REFERENCE TO MIL SPEC:
Available in FM10 on QPL for
MIL-PRF-23419.To order, change 251 to 253 as shown below.
INTERRUPTING RATINGS:
300 amperes at rated voltage VDC.
50 amperes at rated voltage VAC.
ENVIRONMENTAL SPECIFICATIONS:
Operating Temperature:
–55°C to 125°C.
Shock: MIL-STD-202, Method 213, Test Condition I
(100 G’s peak for 6 milliseconds).
Vibration:
MIL-STD-202, Method 201 (10–55 Hz);
Method 204, Test Condition C (55–2000 Hz at 10 G’s Peak).
Moisture Resistance:
MIL-STD-202, Method 106.
PHYSICAL SPECIFICATIONS:
Materials:
Encapsulated, Epoxy-Coated Body; Solder Coated Copper
Wire Leads.
Flammability Rating:
UL 94V0
Soldering Parameters:
Wave Solder — 260°C, 10 seconds maximum.
Solderability:
MIL-STD-202, Method 208.
Lead Pull Force:
MIL-STD-202, Method 211, Test Condition A (will
withstand a 7 lb. axial pull test).
PACKAGING SPECIFICATIONS:
Tape and Reel per EIA-296; T1:
2.062" (52.4mm) taped spacing; 5,000 per reel.
Option:
Radial Lead Version; 0.4" lead spacing; to order, change
251
to
252.
PATENTED
ORDERING INFORMATION:
Std.Type
Mil.Type
Catalog
Catalog
Ampere
Number
Number
Rating
R251
.062
R253
.062
1/16
R251
.125
R253
.125
1/8
R251
.250
R253
.250
1/4
R251
.375
R253
.375
3/8
R251
.500
R253
.500
1/2
R251
.750
R253
.750
3/4
R251
001
R253
001
1
R251
01.5
R253
01.5
1
1
/
2
R251
002
R253
002
2
R251
02.5
2
1
/
2
R251
003
R253
003
3
R251
03.5
3
1
/
2
R251
004
R253
004
4
R251
005
R253
005
5
R251
007
R253
007
7
R251
010
R253
010
10
R251
012
12
R251
015
R253
015
15
100
10
1
0.1
0.01
0.001
1
0.05 0.1
1
10
100
1000
1
1
3
1
3
1
1
2
2
3
3
4
5
7
1
1
1
T
CURRENT IN AMPERES
Nominal
Resistance
Cold Ohms
7.0
1.70
0.665
0.395
0.280
0.175
0.128
0.0823
0.0473
0.0360
0.0290
0.0240
0.0204
0.0155
0.0105
0.00705
0.0055
0.00446
Nominal
Melting I
2
t
A
2
Sec.
0.000113
0.00174
0.0116
0.0296
0.0598
0.153
0.256
0.587
0.405
0.721
1.19
1.58
2.45
4.14
10.4
25.5
45.2
68.8
Voltage
Rating
125
125
125
125
125
125
125
125
125
125
125
125
125
125
125
125
32
32
Average Time Current Curves
F
L
1 A
38.1
(1.5")
38.1
(1.5")
7.11 (.280")
REF.
EPOXY COATING
0.64 (.025")
DIA.
2.41 (.095")
DIA. REF.
NOTE: .025" diameter for
1
/
16
–
10A, .032" diameter for 12
–
15A.
Note: Higher Ampere Ratings Available.
Contact Technical Assistance for Details
QPL
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