© 2012 Littelfuse, Inc.

Specifications are subject to change without notice.

Axial Lead & Cartridge Fuses

251/253 Series

Please refer to www.littelfuse.com/series/251.html

or /253.html for current information.

Average Time Current Curves

Soldering Parameters

100

10

1

0.1

0.01

0.001

0.05 0.1

1

10

100

1000

CURRENT IN AMPERES

Wave Parameter

Lead-Free Recommendation

Preheat:

Temperature Minimum:

100

Temperature Maximum:

150

Preheat Time:

60-180 seconds

Solder Pot Temperature:

260

Solder Dwell Time:

2-5 seconds

Recommended Hand Soldering Parameters:

Heating Time: 5 seconds max.

Note: These devices are not recommended for IR or

Convection Reflow process

Recommended Process Parameters:

Note:

1. Rerating depicted in this curve is in addition to the standard rerating of 25% for

continuous operation.

Temperature Rerating Curve