Fuse Specifications

In electronics and electrical engineering, fuses are used to prevent an overcurrent condition from damaging the circuit that it is designed to protect. Fuses come in many shapes, sizes, current limits, and operational voltages. The primary component in the fuse it usually a metal wire whose length, diameter, and alloy composition is tailored to melt (fuse) at a precise current value.

Two basic types of fuses are available - fast reaction and slow reaction. Fast reaction fuses are used to protect circuit that cannot tolerate even a small amount of excessive current. The sensitive gate of a semiconductor device is an example. Slow reaction (slow-blow) fuses are used for circuits where a higher than normal current condition can be survived for a short time, such as a motor when it first starts (inrush current can be many times greater than the normal run current).

Fuse drawing page   Fuse vendor page

In addition to the sizes represented here, surface mount (SMT) packages are available in standard outlines beginning as small as 0603 (0.063" x 0.031"). See Fuse vendor listing.

Size Diameter

(in.)

Length

(in.)

Standard

Voltages

(V)

Standard

Currents

(A)

1AG (AGA)

glass

1/4 5/8 125

32

1/16,1/10,1/8,1/4

3/8,1/2,6/10,3/4,1

1-1/2,2,2-1/2,3,5

6,7,7-1/2,10,15,

20,25,30

2AG (225)

glass

0.177 0.588 250

125

1/10,1/8,1/4,3/8

1/2,3/4,1,1-1/2,2

2-1/2,3,3-1/2 4,5,6,7,8,10

3AG (AGC)

glass

1/4 1-1/4 250

32

1/20,1/16,1/10,1/8,3/16

2/10,1/4,3/10,3/8,1/2,3/4

1,1-1/4,1-1/2,2,2-1/4

2-1/2,3,4,5,6,7,8,9,10 15,20,25,30

3AB (ABC)

ceramic

1/4 1-1/4 250

125

1/8,1/4,1/2,3/4,1,2

3,4,5,6,7,8,10,12

15,20 25,30

4AG (AG) 9/32 1-1/4
5AG (AGU)

glass

13/32 1-1/2 250

32

1,2,3 4,5,8,10,15,20,25

30,35,40,50,60

7AG (AGW)

glass

1/4 7/8 32 1,1-1/2,2,2-1/2,3

4,5,6,7-1/2,10,15

20,25,30

8AG (AGX)

glass

1/4 1 250

125

32

1/500,1/200,1/100

1/32,1/16,1/10,1/8

2/10,3/16,1/4,3/10

3/8,4/10,1/2,3/4,1

1-1/4,1-1/2,22-1/2,3,4,5,6,7 8,10,15,20,25,30

5x15mm

(C519,C520)

glass

5 mm 15 mm 250

125

125mA,250mA,350mA

375mA,500mA,600mA

750mA,1,1.25,1.5,1.62,2.5,3,3.5,4,5

5x20mm

(GDA,GDB)

glass

5 mm 20 mm 250 50mA,63mA,80mA,100mA

125mA,160mA,200mA

250mA,315mA,400mA,500mA

630mA,800mA,1,1.25,1.6

2,2.5,3.15,4,5,6.3,8,10

Nanofuse 0.080 0.225 125

60

32

1/16,1/8,1/4

3/8,1/2 3/4,1,1-1/2,2

2-1/2,3,3-1/2,4 5,7,10,12,15

SFE 1/4 5/8 to 1-7/16
Automotive

(ATC)

blade

0.207 (W)

0.752 (H)

0.760 32 Black = 1A

Gray = 2A

Violet = 3A

Pink = 4A

Tan = 5A

Brown = 7½

Red = 10A

Blue = 15A

Yellow = 20A

Clear = 25A

Green = 30A

Amber = 40A

Mini Auto

(ATM)

blade

0.15 (W)

0.429 (H)

0.760 32 Gray = 2A

Violet = 3A

Pink = 4A

Tan = 5A

Brown = 7½

Red = 10A

Blue = 15A

Yellow = 20A

Clear = 25A

Green = 30A

Note: The "AG" term comes from Automobile Glass fuse.

 

Current Rating/Derating
Specify fuse current as:

Nominal Operating Current / 0.75, at 25ºC, then derate fuse current above or below 25°C per chart.

Derating: A = Slow Blow

B = Fast

C = Resettable

RF Cafe: Fuse derating chart