Part A
0451007.MRL
Littelfuse Inc.
- Lifecycle
- Active
- Stock
- 4553 Stückzahl
- Package
- 2-SMD
- Series
- Sicherungen
Replacement verdict
Compatible functional replacement candidate
The 0451007.MRL and 0451015.MRL are both fast-acting surface-mount fuses from the same Littelfuse NANO2 series, sharing identical package, voltage rating, and interrupting capacity. The only meaningful difference is the current rating, so the 0451015.MRL can serve as a higher-current functional substitute for the 0451007.MRL only when the circuit's overcurrent protection threshold is re-evaluated and the increased hold current is acceptable.
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 Inc.
- Lifecycle
- Active
- Stock
- 4148 Stückzahl
- Package
- 2-SMD
- Series
- Sicherungen
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | 0451007.MRL | 0451015.MRL | Why it matters |
|---|---|---|---|
| Current Rating | 7 A | 15 A | Determines the maximum continuous current the fuse can carry without opening; a direct functional difference affecting circuit protection sizing. |
| Voltage Rating | 125 VAC / 125 VDC | 125 VAC / 125 VDC | Defines the maximum circuit voltage the fuse can safely interrupt; must meet or exceed the application voltage. |
| Fuse Type | Fast-Acting (Nano2) | Fast-Acting (Nano2) | Indicates the time-current response characteristic; fast-acting fuses protect sensitive components from rapid overcurrent events. |
| Package / Size | Nano2, 6.1 x 2.69 mm SMD | Nano2, 6.1 x 2.69 mm SMD | Physical footprint and mounting style must match the PCB pad layout for drop-in substitutability. |
| Interrupting Rating | 50 A at 125 VAC / 300 A at 125 VDC | 50 A at 125 VAC / 300 A at 125 VDC | Specifies the maximum fault current the fuse can safely clear without rupturing; critical for safety compliance. |
| Nominal Cold Resistance | 0.0105 Ohms | 0.0045 Ohms | Affects voltage drop and power dissipation in the circuit; lower resistance reduces losses but varies with current rating. |
| Melting I²t | 26.5 A²s | 120 A²s | Represents thermal energy required to open the fuse; influences coordination with downstream components during faults. |
| Operating Temperature Range | -55°C to +125°C | -55°C to +125°C | Ensures reliable operation across the application's environmental conditions. |
| Approvals / Compliance | UL, CSA, PSE | UL, CSA, PSE | Certification to safety standards is required for end-product regulatory acceptance. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 0451007.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) | 7 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 | 10.32 | 97.82 |
| Approval Agency | CSA, PSE, UL | CSA, UL |
| Operating Temperature | -55°C ~ 125°C | -55°C ~ 125°C |
Frequently asked questions
What are the 0451007.MRL and 0451015.MRL fuses?
The 0451007.MRL and 0451015.MRL are surface-mount slow-blow ceramic tube fuses from Littelfuse's 451 series. The 0451007.MRL is rated 7 A and the 0451015.MRL is rated 15 A, both with a voltage rating of 125 VAC/VDC and a breaking capacity of 50 A at 125 VAC/VDC.
What is the main difference between the 0451007.MRL and 0451015.MRL?
The primary difference is the current rating: the 0451007.MRL is rated 7 A, while the 0451015.MRL is rated 15 A. Both share the same 451 series platform, 125 VAC/VDC voltage rating, 50 A breaking capacity, slow-blow characteristic, and surface-mount ceramic package.
Are the 0451007.MRL and 0451015.MRL interchangeable?
No. Although they share the same package, voltage rating, and breaking capacity, their current ratings differ (7 A vs 15 A). Substitution must only be done after verifying that the circuit's normal operating current, inrush profile, and overcurrent protection requirements match the replacement fuse's rating, in accordance with the manufacturer's datasheet.
What is the physical package and mounting type of these fuses?
Both the 0451007.MRL and 0451015.MRL are surface-mount (SMD) ceramic tube fuses in the 451 series package, which is a 6.1 mm x 2.69 mm ceramic body with end caps suitable for automated PCB assembly and reflow soldering.
What are the voltage and breaking capacity ratings for these fuses?
Both the 0451007.MRL and 0451015.MRL are rated 125 VAC/VDC with a breaking capacity of 50 A at 125 VAC/VDC, as specified in the Littelfuse 451 series datasheet.
What is the blow characteristic of the 0451007.MRL and 0451015.MRL?
Both fuses are slow-blow (time-lag) type, meaning they tolerate temporary inrush currents above their rated current without opening, which makes them suitable for circuits with inductive or capacitive loads that exhibit startup surges.
What are the typical applications for the 0451007.MRL and 0451015.MRL?
These fuses are typically used for overcurrent protection in power supplies, battery chargers, consumer electronics, and industrial equipment where a surface-mount slow-blow fuse with a 125 VAC/VDC rating and 50 A breaking capacity is required. The 7 A version suits lower-current rails, while the 15 A version suits higher-current rails.
Do the 0451007.MRL and 0451015.MRL have the same operating temperature range?
Yes. Both fuses in the Littelfuse 451 series share the same operating temperature range of -55 °C to +125 °C, as stated in the manufacturer's datasheet.
Are the 0451007.MRL and 0451015.MRL RoHS compliant?
Yes. Both the 0451007.MRL and 0451015.MRL are RoHS compliant and lead-free, consistent with the Littelfuse 451 series environmental specifications.