© 2017 Littelfuse, Inc.

Specifications are subject to change without notice.

Revised: 03/22/17

Radial Leaded > 250R Series

Part Marking System

B

B

C

A

A

Figure 1

E

D

C

E

Figure 2

D

F

F

250

080

XXXX

Voltage Rating

Current Rating

Date Code

(Contact Littelfuse

for additional

information)

Littelfuse

Trademark

Voltage Rating

Current Rating

Date Code

(Contact Littelfuse

for additional

information)

Littelfuse

Trademark

250

120

XXXX

Dimensions

B

B

C

A

A

Figure 1

E

D

C

E

Figure 2

D

F

F

250

080

XXXX

Voltage Rating

Current Rating

Date Code

(Contact Littelfuse

for additional

information)

Littelfuse

Trademark

Voltage Rating

Current Rating

Date Code

(Contact Littelfuse

for additional

information)

Littelfuse

Trademark

250

120

XXXX

Figure 2

Figure 1

Part Number

Figure

A

B

C

D

E

Physical Characteristics

Inches

mm

Inches

mm

Inches

mm

Inches

mm

Inches

mm

Lead (dia)

Material

Max.

Max.

Max.

Max.

Max.

Max.

Min.

Min.

Typ.

Typ.

Inches

mm

250R080

1

0.23

5.8

0.39

9.9

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R080T

1

0.23

5.8

0.39

9.9

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R120

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R120-RA

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R120-RC

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R120-RF

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R120-R1

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R120-R2

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R120-R3

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R120T

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R145

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R145-RA

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R145-RB

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R145T

2

0.27

6.8

0.43

11

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R180

1

0.37

9.5

0.47

12

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

250R180T

1

0.37

9.5

0.47

12

0.18

4.6

0.19

4.7

0.20

5.1

0.026

0.65

Sn/Cu

WARNING

• Users shall independently assess the suitability of these devices for each of their applications

• Operation of these devices beyond the stated maximum ratings could result in damage to the devices and lead to electrical arcing and/or fire

• These devices are intended to protect against the effects of temporary over-current or over-temperature conditions and are not intended to perform as protective devices where such

conditions are expected to be repetitive or prolonged in duration

• Exposure to silicon-based oils, solvents, electrolytes, acids, and similar materials can adversely affect the performance of these PPTC devices

• These devices undergo thermal expansion under fault conditions, and thus shall be provided with adequate space and be protected against mechanical stresses

• Circuits with inductance may generate a voltage (L di/dt) above the rated voltage of the PPTC device.