Type C1F

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Bel Fuse Inc.

300 Executive Drive, Suite 300

West Orange, NJ 07052 USA

+1 201.432.0463

Bel.US.CS@belf.com

belfuse.com/circuit-protection

© 2025 Bel Fuse, Inc.

Rev. C1F Feb2025

Temperature Derating Curve

Average Time Current Curve

Electrical Specifications

Part Number

Ampere

Rating

(A)

Marking

Code

Nominal

Cold

Resistance

(ohms)

Maximum

Volt-drop

@100% In

(Volt) max.

Voltage and

Interrupting

Ratings

Nominal

Melting I²T

@10 In

(A² Sec)

Maximum

Power

Dissipation

@100% In

(W)

Agency

Approvals

0685F0250-XX

250mA

E

2.30

0.813

See Table of

Safety Approvals

on Page 1 for

Voltage and

associated

Interrupting

Ratings

0.0002

0.20

Y

0685F0375-XX

375mA

H

1.25

0.789

0.0007

0.30

Y

0685F0500-XX

500mA

J

0.87

0.693

0.0015

0.35

Y

0685F0750-XX

750mA

M

0.43

0.476

0.0051

0.36

Y

0685F1000-XX

1A

1

0.28

0.421

0.012

0.42

Y

0685F1250-XX

1.25A

P

0.210

0.411

0.023

0.51

Y

0685F1500-XX

1.5A

R

0.165

0.400

0.040

0.60

Y

0685F2000-XX

2A

2

0.068

0.194

0.085

0.39

Y

0685F2500-XX

2.5A

T

0.049

0.198

0.15

0.50

Y

0685F3000-XX

3A

3

0.039

0.166

0.19

0.50

Y

0685F3500-XX

3.5A

Z

0.032

0.164

0.21

0.57

Y

0685F4000-XX

4A

4

0.026

0.164

0.33

0.66

Y

0685F5000-XX

5A

5

0.020

0.164

0.83

0.82

Y

0685F6000-XX

6A

6

0.015

0.163

1.3

0.98

Y

0685F7000-XX

7A

7

0.012

0.154

2.2

1.08

Y

0685F8000-XX

8A

8

0.010

0.148

3.5

1.18

Y

Consult manufacturer for other ratings

NOTES: Test Conditions

All test for ratings 250mA - 5A were conducted with fuse samples soldered on a PCB (1.6mm thick) test board with copper traces measuring

0.035 mm (35μm) nominal thickness (1 oz. clad), 5mm wide and 100mm overall length.

All test for ratings 6A-8A were conducted with fuse samples soldered on a PCB (1.6mm thick) test board with copper traces measuring 0.070

mm (70

μm) nominal thickness (2 oz. clad), 7.5mm wide and 100mm overall length.

Device designed to be mounted with marking facing up.

Device designed to carry rated current for 4 hours minimum. It is recommended that device be operated continuously at no more than 80% of

rated current when in a +25°C ambient, with further derating at elevated ambient temperatures.

Specifications subject to change without notice