85
© 2009 Littelfuse, Inc.
Specications are subject to change without notice.
Surface Mount Fuses
461 Series
Surge Resistant > 461 Series TeleLink® Fuse
Please refer to www.littelfuse.com/series/461.html for current information.
461 Series
461 Series TeleLink® Fuse
Description
Agency Approvals
Electrical Characteristics for Series
Features
t 4VSGBDFNPVOUTVSHF
SFTJTUBOU4MP#MP®GVTF
t .FFU6-SE
&EJUJPOQPXFSDSPTT
SFRVJSFNFOUTTUBOEBSE
BMPOF
t %FTJHOFEUPBMMPX
DPNQMJBODFXJUI5FMDPSEJB
(3$03&BOE5*"
"GPSNFSMZ'$$1BSU
4VSHF4QFDJåDBUJPOT
t 1SPWJEFDPPSEJOBUFE
QSPUFDUJPOXJUI-JUUFMGVTF
4*%"$UPS®5SBOTJFOU
7PMUBHF4VQQSFTTPS574
PSB(SFFOUVCF5.(BT
1MBTNB"SSFTUPSXJUIPVU
TFSJFTSFTJTUPST
t %FTJHOFEUPTFSWF
UIFSFRVJSFNFOUT
PGBXJEFSBOHFPG
UFMFDPNNVOJDBUJPOBOE
OFUXPSLJOHFRVJQNFOU
t "SBUJOHIBTJNQSPWFE
UFNQFSBUVSFSJTF
QFSGPSNBODFVOEFS"
TVSHFDVSSFOUUFTUJOH
XIFODPNQBSFEXJUI
"SBUJOH
t 1SPEVDUJT)BMPHFO'SFF
BOE3P)4DPNQMJBOUBOE
DPNQBUJCMFXJUIMFBE
GSFFTPMEFSBOEIJHIFS
UFNQFSBUVSFQSPåMFT
XIFOPSEFSFEXJUI
4UBOEBSE4JMWFS1MBUFE
#SBTT$BQT
t 4UBOEBSEQSPEVDUJT
3P)4$PNQMJBOUBOE
DPNQBUJCMFXJUIMFBE
GSFFTPMEFSTBOEIJHIFS
UFNQFSBUVSFQSPåMFT
AGENCY AGENCY FILE NUMBER AMPERE RANGE
E10480 500mA - 2A
LR29862 500mA - 2A
% of Ampere
Rating Opening Time
 IPVST.JOJNVN
 TFD.JOTFDT.BY
5IF-JUUFMGVTF4FSJFT5FMF-JOL®4VSGBDF.PVOU
4VSHF3FTJTUBOU'VTFPGGFSTPWFSDVSSFOUQSPUFDUJPOGPS
BXJEFSBOHFPGUFMFDPNBQQMJDBUJPOTXJUIPVUSFRVJSJOH
BTFSJFTSFTJTUPS8IFOVTFEJODPOKVODUJPOXJUIB
-JUUFMGVTF4*%"$UPS®5SBOTJFOU7PMUBHF4VQQSFTTPS574
PSB(SFFOUVCF5.(BT1MBTNB"SSFTUPSUIJTDPNCJOBUJPO
QSPWJEFTBDPNQMJBOUTPMVUJPOGPSTUBOEBSETBOE
SFDPNNFOEBUJPOTTVDIBT(3o$PSF5*""6-
&/*&$BOE*56,BOE,5IFDPPSEJOBUJPO
SFRVJSFNFOUDPOUBJOFEJO(3o$PSFBOE*56,
NBZSFRVJSFBTFSJFTPGJNQFEBODFEFWJDFT
Applications
t 5&+BOE)%4-
t 4-*$JOUFSGBDFQPSUJPOPG'JCFSUPUIF$VSC'55$BOE
'JCFSUPUIF1SFNJTFT'551
t /PO'JCFS4-*$JOUFSGBDFGPS$FOUSBM0GåDF$0
MPDBUJPOTBOE3FNPUF5FSNJOBMT35
t Y%4-BQQMJDBUJPOTTVDIBT"%4-"%4-7%4-BOE
7%4-
t &UIFSOFU#BTF5
t 1054BQQMJDBUJPOTTVDIBTNPEFNTBOTXFSJOH
NBDIJOFTUFMFQIPOFTGBYNBDIJOFTBOETFDVSJUZ
TZTUFNT
t *4%/i6wJOUFSGBDF
t #BZTUBUJPO5&+5%4USVOLDBSET
Telecom Nano¥ Fuse Temperature Reading
 ¡$¡'
 ¡$¡'
Maximum Temperature Rise
Higher Currents and PCB layout designs can affect this parameter.
Readings are measured at rated current after temperature stabilizes.
Revised: June 8, 2011
Introduction to Circuit Protection
Introduction to Circuit Protection
Transientology
86 © 2009 Littelfuse, Inc.
Specications are subject to change without notice.
Surface Mount Fuses
461 Series
Surge Resistant > 461 Series TeleLink® Fuse
Please refer to www.littelfuse.com/series/461.html for current information.
Electrical Specications by Item
Ampere
Rating
(A)
Amp Code
Max
Voltage
Rating
(V)
Interrupting
Rating
Nominal Cold
Resistance (Ohms)
Nominal Melting
It (A2sec)
Agency Approvals
  
"!7"$
"!7%$
 YY
    YY
    YY
*UJTDBMDVMBUFEBUNTFDTPSMFTT*UBUUJNFTSBUFEDVSSFOUIBTBUZQJDBMWBMVFPG"TFD""TFD""TFD"
t 5ZQJDBMJOEVDUBODFO)VQUP.)[
t 3FTJTUBODFDIBOHFTGPSFWFSZ¡$
t 3FTJTUBODFJTNFBTVSFEBUSBUFEDVSSFOU
GR 1089 Inter-building requirements
GR 1089 1st level lighting surge inter-building
(Equipment under test can not be damaged and must
continue to operate properly)
Surge
Minimum
Peak
Voltage
(V)
Minimum
Peak
Current
(A)
Max.
Rise/Min.
Decay
(μs)
Repetitions
Each
Polarity
Fuse
Choices
    
    
    
4   
   
GR 1089 2nd level lightning surge telecom port
(Equipment under test shall not become a re or
electrical safety hazard)
Surge
Minimum
Peak
Voltage
(V)
Minimum
Peak
Current (A)
Max.
Rise/Min.
Decay
(μs)
Repe-
titions
Each
Polarity
Fuse
Choices
   
"MUFS
OBUJWF    
*GTVGåDJFOUTFSJFTSFTJTUBODFJTVTFEUIFOUIFGVTFNBZCFVTFEJOUFTUDPOEJUJPOT
5IFGVTFXJMMPQFOEVSJOHUIFTFUFTUDPOEJUJPOT5IFXJMMOPUPQFOUIVT
QSPWJEJOHPQFSBUJPOBMDPNQMJBODF
Average Time Current Curves
10001001010.1
0.001
0.01
0.1
1
10
100
CURRENT IN AMPERES
TIME IN SECONDS
1.25A
2A
.500A
Temperature Rerating Curve
/PUF
 3FSBUJOHEFQJDUFEJOUIJTDVSWFJTJOBEEJUJPOUPUIFTUBOEBSESFSBUJOHPGGPS
DPOUJOVPVTPQFSBUJPO
87
© 2009 Littelfuse, Inc.
Specications are subject to change without notice.
Surface Mount Fuses
461 Series
Surge Resistant > 461 Series TeleLink® Fuse
Please refer to www.littelfuse.com/series/461.html for current information.
461 Series
GR 1089 AC power fault 1st level inter-building (fuse
not allowed to open)
GR 1089 AC power fault 2nd level (fuse can open but
must open in a safe and controlled manner)
Test Vrms
Short
Circuit
Current
(A)
Hits Duration Primary
Protector
Fuse
Choices
  NJO SFNPWFE 
  NJO SFNPWFE 

  TFD SFNPWFE 
4  TFD PQFSBUJWF 
%JBHSBN %JBHSBN  TFDT SFNPWFE 
  TFDT SFNPWFE 
  TFDT SFNPWFE 
 TFDT SFNPWFE 
 TFD JOQMBDF 
Test
Circuit Vrms
Short
Circuit
Current
(A)
Duration Fuse
  NJO 
  TFDT 
 TFDT 
4  NJO 
%JBHSBN %JBHSBN NJO 
Fuse must open before wiring simulator fuse (MDL 2.0).
Surge Voltage (V) Waveform (μs) Current (A) Repetitions Recommended Fuse
.FUBMMJD"  Y  FBQPMBSJUZ 
-POHJUVEJOBM"  Y  FBQPMBSJUZ 
.FUBMMJD#  Y  FBQPMBSJUZ 
-POHJUVEJOBM#  Y  FBQPMBSJUZ 
TIA –968-A (formerly FCC Part 68) Surge Waveforms (fuse can not open during type B events)
UL 60950 requirements
UL60950 (EN 60950) (formerly UL 1950) Power Cross (L
= longitudinal, M = metallic)
Test
Number Voltage (V) Current (A) Time Fuse
Choices
-   TFDT 
-  TFDT 
-   NJO 
-   NJO 
-   NJO 
.   TFDT 
.  TFDT 
.   NJO 
.   NJO 
4election of test number depends on current limiting F re enclosure/spacing of end product
t "8(MJOFDPSESFNPWFT-.UFTUSFRVJSFNFOU
t -DPOEVDUFEPOMZJGQSPEVDUEPFTOPUQBTTTFDUJPO
t -.-.-.DPOEVDUFEJGOPUJOBåSFFODMPTVSF
Fuse must open before the wiring simulator fuse (MDL 2.0).
UL60950 (EN 60950) (formerly UL 1950) Impulse Test and Steady-State Electric Strength Test
Test Voltage (V) Current (A) Waveform Repetitions Fuse Choices
Impulse
'PSIBOEIFMEVOJUT   YNT XTFDTSFTU 
/POIBOEIFME   YNT XTFDTSFTU 
Steady-State
'PSIBOEIFMEVOJUT  )[ 
/POIBOEIFME  )[ 
'PSUIFUZQF"FWFOUTUIFGVTFXJMMPQFOQSPWJEJOHOPOPQFSBUJPOBMDPNQMJBODF5IFXJMMOPUPQFOQSPWJEJOHGPSPQFSBUJPOBMDPNQMJBODFXJUI5*""UZQF"TVSHFFWFOUT
L
F1.25A T3.12
(.123")
3.12
(.123")
10.10
(.397")
3.25
(.128")
3.43
(.135")
12.6
(.496")
6.10
(.240")
Recommended Pad Layout
1.70 typ
(.067")
Dimensions
Introduction to Circuit Protection
Introduction to Circuit Protection
Transientology
88 © 2009 Littelfuse, Inc.
Specications are subject to change without notice.
Surface Mount Fuses
461 Series
Surge Resistant > 461 Series TeleLink® Fuse
Please refer to www.littelfuse.com/series/461.html for current information.
Materials Body:$FSBNJD
Terminations:4JMWFSQMBUFE$BQT
Product Marking #SBOE-PHP"NQFSF3BUJOH5
Operating
Temperature ¡$UP¡$
Moisture Sensitivity
Level -FWFM+45%$
Solderability *&$¡$JNNFSTJPO
TFDPOET
Resistance to
Dissolution of
Metallization
*1$&*"+45%"5FTU%¡$GPS
TFDPOET
Product Characteristics
Reow Condition 1CoGSFFBTTFNCMZ
Pre Heat
- Temperature Min (Ts(min))¡$
- Temperature Max (Ts(max))¡$
- Time (Min to Max) (ts)oTFDPOET
Average Ramp-up Rate (Liquidus Temp
(TL) to peak) ¡$TFDPOENBY
TS(max) to TL - Ramp-up Rate ¡$TFDPOENBY
Reow - Temperature (TL) (Liquidus) ¡$
- Temperature (tL)oTFDPOET
Peak Temperature (TP)¡$
Time within 5°C of actual peak
Temperature (tp)oTFDPOET
Ramp-down Rate ¡$TFDPOENBY
Time 25°C to peak Temperature (TP)NJOVUFTNBY
Do not exceed ¡$
Soldering Parameters
Packaging
Part Numbering System
Packaging Option Packaging Specication Quantity Quantity &
Packaging Code
NN5BQFBOE3FFM &*"34*&$QBSU  ER
Thermal Shock
.*-45%.FUIPE5FTU
$POEJUJPO#¡$UP¡$
NJOVUFT!FBDIFYUSFNF
Mechanical Shock
.*-45%.FUIPE5FTU
$POEJUJPO")BMG4JOF(hT
NTFDTEVSBUJPO
High Frequency
Vibration
.*-45%.FUIPE5FTU
$POEJUJPO%
Moisture Resistance .*-45%.FUIPEDZDMFT
Terminal Strength #PBSEEFýFDUJPOQFS&*"*4
NNEFýFDUJPOGPSNJOVUF
Terminal Attachment .*-45%.FUIPE5FTU
$POEJUJPO"MCTBQQMJFEUPFOEDBQT
0461 1.25 E R
SERIES
AMP Code*
QUANTITY Code
PACKAGING Code
3FGFSUP&MFDUSJDBM
$IBSBDUFSJTUJDTUBCMF
&QDT
35BQFBOE3FFM *Example:
BNQQSPEVDUJT002.ER
BNQQSPEVDUTIPXOBCPWF
Time
Temperature
TP
TL
TS(max)
TS(min)
25
tP
tL
tS
time to peak temperature
(t 25ºC to peak)
Ramp-down
Ramp-up
Preheat
Critical Zone
TL to TP