3
Cartridge and Axial Lead Fuses
©2008 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com for current information.
Revised: August 14, 2008
251/253 Series
PICO® II > Very Fast-Acting > 251/253 Series
Cartridge and Axial Lead Fuses
PICO® II > Very Fast-Acting > 251/253 Series
Materials &ODBQTVMBUFE&QPYZ$PBUFE
#PEZ1VSF5JODPBUFE$PQQFSXJSFMFBET
Solderability .*-45%.FUIPE
Lead Pull Force .*-45%.FUIPE5FTU$POEJUJPO
"XJMMXJUITUBOEBMCTBYJBMQVMMUFTU
Fuses To MIL SPEC
4FSJFTJTBWBJMBCMFJO'.PO
21-GPS.*-13'5PPSEFSDIBOHF
251 to 253
Product Characteristics
Operating Temperature o$UP$
Shock
.*-45%.FUIPE5FTU
Condition I (100 G’s peak for 6
NJMMJTFDPOET
Vibration
.*-45%.FUIPEo
)[.FUIPE5FTU$POEJUJPO$
o)[BU(T1FBL
Moisture Resistance .*-45%.FUIPE
Resistance to Soldering
Heat
8JUITUBOETTFDPOETBCPWFOC
and up to 260º$NBYJNVN
Flammability Rating UL 94V–0
Wire Diameter:
0.64 (.025") for 0.62-10.0 amp,
0.81 (.032") for 15 amp
Wire Diameter:
0.64 (.025") for 0.62-10.0 amp,
0.81 (.032") for 12-15 amp
2.80 (.11")
MAX 6.35 (.25")
tape
5.0 (.197")
6.35 (.25")
tape
38.1
(1.5")
38.1
(1.5")
7.11 (.280")
83.31 (3.28")
253 series
(T3 lead length)
F
L1 A
F
L1 A
73.0 (2.874")**
F
L
1 A
F
L
1 A
27.78
(1.094")
27.78
(1.094")
7.11 (.280")
62.7 (2.468")
52.4 (2.062")*
2.80 (.11")
MAX 6.35 (.25")
tape
5.0 (.197")
6.35 (.25")
tape
251 series
(T1 lead length)
Dimensions
Packaging
Part Numbering System
Packaging Option Packaging Specification Quantity &
Packaging Code
5NN5BQFBOE3FFM EIA 296
1MFBTFSFGFSUPBWBJMBCMFRVBOUJUJFT
BCPWFJO1BSU/VNCFSJOH4ZTUFNw
5NNh5BQFBOE3FFM EIA 296
0251 xxxx N R T1 L
RoHS
Lead Length
Type of Packaging
Quantity
Current Rating
Series
The default lead length for Ammo pack and
Loose pack is now T1 for 251 series, and
remains T3 for 253 series, therefore:
T1 = 52.4mm (2.062”), 251 series only*
Blank = 52.4mm (2.062”) for 251 series*
or 73mm (2.874”) for 253 series**
R = Reel
A = Ammo Pack
X = Loose Pack
N = 5000
P = 2000
M = 1000
H = 100
V = 5
Refer to Amp Code column of
Electrical Characteristics Table
251
= Standard type
253
= Military type
5IFEFGBVMUMFBEMFOHUIGPSCPUIBNNPQBDLBOEMPPTFQBDLJT5GPSBOEJT5GPS
/PUFT 5EJNFOTJPOJTEFmOFEBTUIFMFOHUIPGUIFDPNQPOFOUCFUXFFOUIFUXPUBQFT5IFGVMMDPNQPOFOUMFOHUIJTNN T1 length is for 251 series only.
5EJNFOTJPOJTEFmOFEBTUIFMFOHUIPGUIFDPNQPOFOUCFUXFFOUIFUXPUBQFT5IFGVMMDPNQPOFOUMFOHUIJTNNwT3 length is for 253 series only.