Cut Sheet

© 2017 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 01/31/17
Axial Lead & Cartridge Fuses
5×20 mm > Slo-Blo
®
Fuse > 239 Series
Average Time Current CurvesTemperature Re-rating Curve
CURRENT IN AMPERES
10000
0.200A 0.250A 0.300A 0.400A 0.500A 0.600A 0.700A 0.750A 0.800A 1A 1.25A 1.6A 2A 2.5A 3A 3.15A 4A 5A 7A
1000
100
10
1
0.1
0.01
0.1 110100 1000
0.001
TIME IN SECONDS
Soldering Parameters - Wave Soldering
Dwell Time
0
20
40
60
80
100
120
140
160
180
200
220
240
260
280
300
0
10 20 30 40 50 60 70 80 90
100 110 120 130 140 150 160 170 180 190 200 210 220 230
240
Time (Seconds)
Temperature (°C) - Measured on bottom side of board
Cooling Time
Preheat Time
Wave Parameter Lead-Free Recommendation
Preheat:
(Depends on Flux Activation Temperature)
(Typical Industry Recommendation)
Temperature Minimum:
100
°C
Temperature Maximum:
150
°C
Preheat Time: 60-180 seconds
Solder Pot Temperature:
260
°C Maximum
Solder Dwell Time: 2-5 seconds
Recommended Hand-Solder Parameters:
Solder Iron Temperature: 350°C +/- 5°C
Heating Time: 5 seconds max.
Note: These devices are not recommended for IR or
Convection Reflow process.
Recommended Process Parameters:
Note:
Rerating depicted in this curve is in addition to the standard derating of 25% for
continuous operation.