© 2018 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 06/06/18
Axial Lead & Cartridge Fuses
3AG > Fast Acting > 312/318 Series
312/318 Series Lead-Free 3AG, Fast-Acting Fuse
The 3AG Fast-Acting Fuse solves a broad range
of application requirements while offering reliable
performance and cost-effective circuit protection.
Agency Approvals
Agency Agency File Number Ampere Range
E10480 0.062A - 25A
29862 312 Series: 0.062A - 30A
318 Series: 0.062A - 10A
PS
E
(312 Series)
NBK040205-E10480B
NBK040205-E10480F
1A - 5A
6A - 10A
(318 Series)
NBK040205-E10480D
NBK040205-E10480H
1A - 5A
6A - 10A
E10480 318 Series: 12A - 30A
SU05001-6008
SU05001-5005
SU05001-5006
1A - 2A
3A - 6A
7A - 10A
N/A 0.062A - 10A
Features
Electrical Characteristics for Series
Applications
% of Ampere
Rating Ampere Rating Opening Time
100% 0.062A – 35A 4 hours, Minimum
135% 0.062A – 35A 1 hour, Maximum
200%
0.062A – 10A 5 sec., Maximum
12A – 30A 10 sec., Maximum
35A 20 sec., Maximum
RoHS
Pb
In accordance with UL
Standard 248-14
Available in cartridge
and axial lead format
and with various forming
dimensions
RoHS compliant and
Lead-free
Used as supplementary protection in appliance or
utilization equipment to provide individual protection for
components or internal circuits.
PS
E
Description
Application testing is strongly recommended.
Additional Information
Datasheet Samples
Resources
Datasheet Samples
Resources
312 Series
318 Series
312 Series
318 Series
312 Series 312 & 318 Series
318 Series
Accessories
For recommended fuse accessories for this product series,
see ‘Recommended Accessories’ section.
© 2018 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 06/06/18
Axial Lead & Cartridge Fuses
3AG > Fast Acting > 312/318 Series
Amp
Code
Ampere
Rating (A)
Voltage
Rating
(V)
Interrupting
Rating
Nominal
Cold
Resistance
(Ohms)
Nominal
Melting
I2t (A2 sec)
Agency Approvals
PS
E
.062 0.062 250
35A@250Vac
10KA@125Vac
24.7000 0.000249 x x x
.10 0 0.1 250 11.2800 0.00171 x x x
.125 0.125 250 7.1450 0.00289 x x x
.150 0.15 250 5.1300 0.00550 x x x
.175 0.175 250 3.8750 0.00960 x x x
.187 0.187 250 3.4200 0.0128 x x x
.200 0.2 250 3.0200 0.0165 x x x
.250 0.25 250 2.0100 0.0355 x x x
.300 0.3 250 1.4050 0.0689 x x x
.375 0.375 250 0.8250 0.185 x x x
.500 0.5 250 0.4980 0.483 x x x
.600 .6 250 0.3620 0.880 x x x
.750 0.75 250 0.2445 1.84 x x x
0 01. 1 250 0.1900 0.760 x x x x x
1.25 1.25 250
100A@250Vac
10KA@125Vac
0.1385 1.45 x x x x x
01. 5 1. 5 250 0.1036 2.35 x x x x
01. 6 1. 6 250 0.0934 2.80 x x x x x
1.75 1.75 250 0.0856 3.60 x x x x
01. 8 1. 8 250 0.0825 3.85 x x x x
002. 2 250 0.0704 5.20 x x x x x
2.25 2.25 250 0.0594 7.20 x x x x x
02.5 2.5 250 0.0513 9.54 x x x x x
003. 3 250 0.0427 14.0 x x x x x
004. 4 250
200A@250Vac
10KA@125Vac
0.0293 28.5 x x x x x
005. 5 250 0.0224 50.0 x x x x x
006. 6 250 0.0178 118.0 x x x x x
0 0 7. 7 250 0.0146 81.0 x x x x x
008. 8 250 0.0122 166.0 x x x x x
010. 10 250 0.0093 298.0 x x x x x
012. 12 32
300A@32 Vac
0.0072 234.6 x x** x
015. 15 32 0.0052 490.5 x x** x
020. 20 32 0.0035 1414 x x** x
025. 25 32 0.0024 2041 x x** x
030. 30 32 0.0019 3717 x** x
035. 35 32 0.0013 7531
NOTES:
** For 318 Series 12A to 30A, the agency approval is only cURus.
Electrical Characteristic Specifications by Item
© 2018 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 06/06/18
Axial Lead & Cartridge Fuses
3AG > Fast Acting > 312/318 Series
Average Time Current Curves
1000
10 0
10
1
0.1
0.01
110 10 0
0.01 0.1
.062 A
.125 A
.250 A
.375 A
.500 A
.750 A
1 A
1.5 A
2 A
2.5 A
3 A
4 A
5 A
6 A
7 A
8 A
10 A
0.005
TIME IN SECONDS
CURRENT IN AMPERES
Temperature Re-rating Curve
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:
Please contact Littelfuse for more details on those T-C Curves of other ampere
ratings which are not published.
Note:
Rerating depicted in this curve is in addition to the industry practice derating
of 25% for continuous operation.
© 2018 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 06/06/18
Axial Lead & Cartridge Fuses
3AG > Fast Acting > 312/318 Series
312 000 Series
(cartridge)
318 000 Series
(axial leaded)
6.35±0.3
(.25")
32.72±1.12
(1.288")
31.75±1.12
(1.25")
6.985±0.3
(.275")
Axial Lead Diameter:
0.81±0.05 (.032")
Axial Lead Material:
Tin-coated copper
Axial Lead Length:
Standard Length:
39.68 (1.56") TYP.
Short Lead Option:
12.70 (0.50”) TYP
Product Characteristics
Packaging
Materials
Body: Glass
Cap: Nickel–plated brass
Leads: Tin–plated Copper
Terminal Strength MIL-STD-202, Method 211,
Test Condition A
Solderability MIL-STD-202 method 208
Product Marking
Cap1: Brand logo, current and voltage
ratings
Cap2: Series and agency approval
marks
Operating
Temperature –55ºC to +125ºC
Thermal
Shock
MIL-STD-202, Method 107, Test Condition B: (5
cycles -65°C to +125°C)
Vibration MIL-STD-202, Method 201
Humidity
MIL-STD-202, Method 103,
Test Condition A: High RH (95%),
and Elevated temperature (40°C) for 240 hours
Salt Spray MIL-STD-202, Method 101,
Test Condition B
Part Numbering System
0312 MX Pxxxx
Lead-free
Packaging Code
Quantity Code
Amp Code
Series
X = Filler
M = 1000
Refer to Amp Code column of
Electrical Characteristics Table
312 = Cartridge
318 = Axial Leaded
Dimensions
Measurements displayed in millimeters (inches)
Packaging Option Packaging Specification Quantity Quantity &
Packaging Code Taping Width
312 Series
Bulk N/A 1000 MX N/A
Bulk N/A 100 HX N/A
318 Series
Bulk N/A 1000 MX N/A
Bulk N/A 100 HX N/A
Bulk N/A 1000 MXB N/A
© 2018 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 06/06/18
Axial Lead & Cartridge Fuses
3AG > Fast Acting > 312/318 Series
Recommended Accessories
Accessory
Type Series Description
Max
Application
Voltage
Max
Application
Amperage
Holder
155100 Twist-Lock In-Line Fuseholder 32 20
342 Traditional Panel Mount Fuseholder 250 20
346 Panel Mount Flip-Top Shock-Safe Fuseholder 250 15
345 Shock-Safe Fuseholder with PC Mount, Solder Mount and Panel Mount options 250 20
Block 354 Low Profile OMNI-BLOK® Fuse Block 600 30
359 High Current Screw Terminal Fuse Block 30
Clip 122 High Current Traditional PC Board Fuse Clip 1000 30
101 Rivet/Eyelet Type Fuse Clip 1000 15
Notes:
1. Do not use in applications above rating.
2. Please refer to fuseholder data sheet for specific re-rating information.
3. Please contact factory for applications greater than the max voltage and amperage shown.
Disclaimer Notice - Information furnished is believed to be accurate and reliable. However, users should independently evaluate the suitability of and test each
product selected for their own applications. Littelfuse products are not designed for, and may not be used in, all applications. Read complete Disclaimer Notice at:
www.littelfuse.com/disclaimer-electronics.