Littelfuse 250R Series User Manual
Poly-fuse, Resettable ptcs, 250r series
97
Revised: August 31, 2011
POLY-FUSE
®
Resettable PTCs
© 2011 Littelfuse, Inc
250R Series
Radial Leaded > 250R Series
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/250R.html for current information.
250R S
eries
The 250R Series is designed to protect against short
duration high voltage fault currents (power cross or power
induction surge) typically found in telecom applications
(250Vrms). The series can be used to help telecom
networking equipment meet the protection requirements
specified in ITU K.20 and K.21.
Electrical Characteristics
Part Number
I
hold
(A)
I
trip
(A)
V
max
V
int
/ V
op
I
max
(A)
P
d
typ.
(W)
Maximum Time
To Trip
Resistance
Agency
Approvals
Current
(A)
Time
(Sec.)
R
min
(Ω)
R
typ
(Ω)
R
1max
(Ω)
250R080
0.08
0.16
250/60
3
1
0.35
3
14
22
33
X
X
250R080T
0.08
0.16
250/60
3
1
0.35
3
15
22
33
X
X
250R120
0.12
0.24
250/60
3
1
1
1.5
4
8
16
X
X
250R120-RA
0.12
0.24
250/60
3
1
1
1.0 7
9
16
X
X
250R120-RC
0.12
0.24
250/60
3
1
1
0.85
5.4
7.5
14
X
X
250R120-RF
0.12
0.24
250/60
3
1
1
0.7
6
10.5
16
X
X
250R120-R1
0.12
0.24
250/60
3
1
1
0.8
6
9
16
X
X
250R120-R2
0.12
0.24
250/60
3
1
1
0.7
8 10.5
16
X
X
250R120-R3
0.12
0.24
250/60
3
1
1
1
8
10
16
X
X
250R120T
0.12
0.24
250/60
3
1
1
1.2
7
12
16
X
X
250R145
0.145
0.29
250/60
3
1
1
2.5
3
6
14
X
X
250R145-RA
0.145
0.29
250/60
3
1
1
5
3
5.5
12
X
X
250R145-RB
0.145
0.29
250/60
3
1
1
2.5
4.5
6
14
X
X
250R145T
0.145
0.29
250/60
3
1
1
2.0
5.4
7.5
14
X
X
250R180
0.18
0.65
250/60
10
1.8
1
21
0.8
2.2
4
X
X
250R180T
0.18
0.65
250/60
10
1.8
1
20
1.4
3.9
4.5
X
X
Items with T at end of part number = pre-tripped device. See Part Ordering Number System section of this data sheet for additional information.
Description
Features
Applications
toIPMEDVSSFOU
range, 60VDC operating
voltage
t7"$JOUFSSVQUSBUJOH
t'BTUUJNFoUPUSJQ
t#JOOFEBOETPSUFEOBSSPX
resistance ranges available
t3P)4DPNQMJBOU -FBE
'SFFBOE)BMPHFO'SFF
t$VTUPNFS1SFNJTFT
Equipment (CPE)
t$FOUSBM0GmDF $0
telecom centers
t-"/8"/FRVJQNFOU
t"DDFTTFRVJQNFOU
250R Series
Agency Approvals
AGENCY
AGENCY FILE NUMBER
E183209
R50120008
I
hold
)PMEDVSSFOUNBYJNVNDVSSFOUEFWJDFXJMMQBTTXJUIPVUUSJQQJOHJO¡$TUJMMBJS
I
trip
5SJQDVSSFOUNJOJNVNDVSSFOUBUXIJDIUIFEFWJDFXJMMUSJQJO¡$TUJMMBJS
V
int
.BYJNVNWPMUBHFUIFEFWJDFDBOXJUITUBOEXJUIPVUEBNBHFBUSBUFEDVSSFOU *NBY
V
op
= The device regular operation voltage
I
NBY
.BYJNVNGBVMUDVSSFOUEFWJDFDBOXJUITUBOEXJUIPVUEBNBHFBUSBUFEWPMUBHF 7
NBY
)
P
d
1PXFSEJTTJQBUFEGSPNEFWJDFXIFOJOUIFUSJQQFETUBUFBU¡$TUJMMBJS
R
min
= Minimum resistance of device in initial (un-soldered) state.
R
typ
= Typical resistance of device in initial (un-soldered) state.
R
NBY
.BYJNVNSFTJTUBODFPGEFWJDFBU¡$NFBTVSFEPOFIPVSBGUFSUSJQQJOH
Caution: Operation beyond the specified rating may result in damage and possible arcing
and flame.
&GGFDUJWF+BOVBSZ BMM315$QSPEVDUTXJMMCFNBOVGBDUVSFE)BMPHFO'SFF )' &YJTUJOH/PO)BMPHFO'SFF315$QSPEVDUTNBZDPOUJOVFUPCFTPME VOUJMTVQQMJFTBSFEFQMFUFE