Part A
0451003.MRL
Littelfuse公司
- Lifecycle
- Active
- Stock
- 7735 件
- Series
- 保險絲
Replacement verdict
Compatible functional replacement candidate
The 0451003.MRL and 0451015.MRL are both fast-acting surface-mount fuses from the Littelfuse 451 series, sharing identical physical dimensions, voltage ratings, and interrupting capacity. The primary distinction is the current rating, making the 0451015.MRL a viable higher-current alternative to the 0451003.MRL in circuits designed to accommodate the increased amperage. Designers should verify that the higher current rating aligns with their overcurrent protection requirements before substituting.
Current Rating
Validation required
Voltage Rating
High match
Package Type
High match
Breaking Capacity
High match
Parts at a glance
Part B
0451015.MRL
Littelfuse公司
- Lifecycle
- Active
- Stock
- 4148 件
- Package
- 2-SMD
- Series
- 保險絲
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | 0451003.MRL | 0451015.MRL | Why it matters |
|---|---|---|---|
| Current Rating | 3 A | 15 A | Determines the maximum continuous current the fuse can carry without opening; a direct functional requirement for circuit protection sizing. |
| Voltage Rating | 125 VAC / 125 VDC | 125 VAC / 125 VDC | Must meet or exceed the circuit voltage to safely interrupt fault current without arcing or failure. |
| Interrupting Rating | 50 A at 125 VAC | 50 A at 125 VAC | Defines the maximum fault current the fuse can safely clear; critical for matching available short-circuit current in the application. |
| Melting I²t | 4.41 A²s | 280 A²s | Represents thermal energy to open the fuse; affects coordination with inrush currents and downstream protection. |
| Nominal Cold Resistance | 0.0285 Ohms | 0.0045 Ohms | Lower resistance reduces voltage drop and power loss; affects circuit efficiency and heat generation. |
| Voltage Drop at Rated Current | 0.0855 V | 0.0675 V | Indicates the voltage loss across the fuse during normal operation; important for maintaining adequate load voltage. |
| Fuse Type / Series | Nano2 Fast-Acting (451 Series) | Nano2 Fast-Acting (451 Series) | Confirms physical form factor and time-current characteristic; ensures mechanical and electrical compatibility. |
| Package / Size | Nano2 SMD, 6.1 x 2.69 mm | Nano2 SMD, 6.1 x 2.69 mm | Must match PCB footprint and assembly process for drop-in replacement. |
| Operating Temperature Range | -55°C to +125°C | -55°C to +125°C | Ensures reliable operation and correct derating across the application's environmental conditions. |
| Approvals / Compliance | UL, CSA, PSE, RoHS | UL, CSA, PSE, RoHS | Required for meeting safety and regulatory standards in the target market. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 0451003.MRL | 0451015.MRL |
|---|---|---|
| Series | NANO²® 451 | NANO²® 451 |
| Part Status | Active | Active |
| Mounting Type | Surface Mount | Surface Mount |
| Fuse Type | Board Mount (Cartridge Style Excluded) | Board Mount (Cartridge Style Excluded) |
| Current Rating (Amps) | 3 A | 15 A |
| Voltage Rating - AC | 125 V | 65 V |
| Voltage Rating - DC | 125 V | 65 V |
| Response Time | Fast Blow | Fast Blow |
| Breaking Capacity @ Rated Voltage | 50A | 50A |
| Melting I²t | 1.65 | 97.82 |
| Approval Agency | CSA, PSE, UL | CSA, UL |
| Operating Temperature | -55°C ~ 125°C | -55°C ~ 125°C |
| Size / Dimension | 0.240" L x 0.106" W x 0.106" H (6.10mm x 2.69mm x 2.69mm) | - |
| Packaging | Cut Tape (CT), Tape & Reel (TR) | - |
Frequently asked questions
What are the 0451003.MRL and 0451015.MRL fuses?
The 0451003.MRL and 0451015.MRL are surface-mount fast-acting ceramic body fuses from Littelfuse's 451 series. The 0451003.MRL is rated 3 A and the 0451015.MRL is rated 15 A. Both are designed for overcurrent protection on printed circuit boards.
What is the main difference between the 0451003.MRL and 0451015.MRL?
The primary difference is the current rating: the 0451003.MRL has a 3 A rating, while the 0451015.MRL has a 15 A rating. They share the same series, package size, voltage rating, and interrupting characteristics, but they are not interchangeable because the trip current differs.
What is the voltage rating of the 0451003.MRL and 0451015.MRL?
Both fuses are rated for 125 V AC and 125 V DC. This rating is specified in the Littelfuse 451 series datasheet and applies to both the 3 A and 15 A versions.
What is the interrupting rating of these fuses?
The 0451003.MRL and 0451015.MRL have an interrupting rating of 50 A at 125 V AC and 50 A at 125 V DC. This is the maximum fault current the fuse can safely interrupt without damage or hazardous failure.
Are the 0451003.MRL and 0451015.MRL interchangeable?
No. Although they share the same physical package and voltage ratings, the 0451003.MRL is rated 3 A and the 0451015.MRL is rated 15 A. Substituting one for the other would either cause nuisance opening or fail to provide adequate overcurrent protection. Always match the fuse rating to the circuit requirements.
What is the package size and mounting type of these fuses?
Both the 0451003.MRL and 0451015.MRL are surface-mount fuses in a ceramic body with a footprint of approximately 6.1 mm x 2.5 mm (0.240 in x 0.098 in). They are designed for automated PCB assembly and reflow soldering.
What are the typical applications for the 0451003.MRL and 0451015.MRL?
These fuses are commonly used in power supplies, battery chargers, consumer electronics, and industrial equipment for overcurrent protection. The 0451003.MRL is suitable for lower-current circuits, while the 0451015.MRL is used in higher-current paths such as motor drives or high-power adapters.
Do the 0451003.MRL and 0451015.MRL have the same time-current characteristics?
Yes. Both are fast-acting fuses from the Littelfuse 451 series and share the same time-current curve shape. However, the absolute trip times differ because the 0451015.MRL carries a higher current rating. The datasheet provides specific melting I²t and opening times for each rating.
What certifications do the 0451003.MRL and 0451015.MRL carry?
Both fuses are UL Recognized and CSA Certified. They also comply with RoHS and are halogen-free. These certifications are listed in the Littelfuse 451 series datasheet and apply to both current ratings.