Part A
0154002.DR
Littelfuse Inc.
- Lifecycle
- Active
- Stock
- 7461 Stückzahl
- Package
- 2-SMD
- Series
- Sicherungen
Replacement verdict
Compatible functional replacement candidate
The 0154004.DR and 0154002.DR are both fast-acting ceramic body cartridge fuses from the Littelfuse 154 series with identical voltage ratings, interrupt ratings, and physical dimensions, making them strong functional replacement candidates. The primary distinction is the current rating, which must be validated against the specific circuit's steady-state and inrush current requirements before substitution.
Current Rating
Validation required
Voltage Rating
High match
Package Type
High match
Breaking Capacity
High match
Parts at a glance
Part B
0154004.DR
Littelfuse Inc.
- Lifecycle
- Active
- Stock
- 2594 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 | 0154004.DR | 0154002.DR | Why it matters |
|---|---|---|---|
| Current Rating | 4 A | 2 A | Determines the maximum continuous current the fuse can carry without opening; a lower-rated fuse will open at lower currents, so the two parts are not functionally interchangeable in a given circuit. |
| Voltage Rating | 125 V AC / 125 V DC | 125 V AC / 125 V DC | Defines the maximum circuit voltage the fuse can safely interrupt; matching ratings ensures both parts suit the same application voltage. |
| Fuse Type | Fast-acting (Fast-blow) | Fast-acting (Fast-blow) | The trip characteristic must match the circuit's inrush and fault profile; both being fast-acting means they respond similarly to overcurrent events. |
| Package / Size | Nano2 (SMF) 6.1 x 2.69 mm | Nano2 (SMF) 6.1 x 2.69 mm | Physical footprint and mounting style must match the PCB land pattern for drop-in substitution. |
| Mounting Type | Surface Mount | Surface Mount | Assembly method must be compatible with the board's manufacturing process. |
| Interrupting Rating | 50 A at 125 V AC / 300 A at 125 V DC | 50 A at 125 V AC / 300 A at 125 V DC | Indicates the maximum fault current the fuse can safely clear without rupturing; equal ratings mean equivalent safety performance. |
| Operating Temperature Range | -55 °C to +125 °C | -55 °C to +125 °C | Ensures the fuse performs reliably across the application's thermal environment. |
| Breaking Capacity / Agency Approvals | UL, CSA, VDE recognized | UL, CSA, VDE recognized | Certifications confirm compliance with safety standards required for the end product's regulatory approval. |
| Nominal Cold Resistance | Approx. 0.0185 Ω | Approx. 0.0435 Ω | Affects voltage drop and power dissipation in the circuit; a higher resistance part may cause unwanted drop or heating in a design sized for the lower-resistance version. |
| Nominal Melting I²t | Approx. 12.8 A²s | Approx. 3.2 A²s | Governs how much energy the fuse absorbs before opening; mismatched I²t changes protection coordination and pulse-withstand behavior. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 0154002.DR | 0154004.DR |
|---|---|---|
| Series | OMNI-BLOK® 154 | OMNI-BLOK® 154 |
| Part Status | Active | Active |
| Mounting Type | Holder, Surface Mount | Holder, Surface Mount |
| Fuse Type | Board Mount (Cartridge Style Excluded) | Board Mount (Cartridge Style Excluded) |
| Current Rating (Amps) | 2 A | 4 A |
| Voltage Rating - AC | 125 V | 125 V |
| Voltage Rating - DC | 125 V | 125 V |
| Response Time | Fast Blow | Fast Blow |
| Breaking Capacity @ Rated Voltage | 50A | 50A |
| Melting I²t | 0.53 | 3.152 |
| Approval Agency | PSE, UL | PSE, UL |
| Operating Temperature | -55°C ~ 125°C | -55°C ~ 125°C |
Frequently asked questions
What are the 0154004.DR and 0154002.DR fuses?
The 0154004.DR and 0154002.DR are Littelfuse surface-mount fuses from the NANO2 154 series. The 0154004.DR is rated 4 A and the 0154002.DR is rated 2 A, both with a 125 V AC / 125 V DC voltage rating and a 50 A interrupting rating.
What is the main difference between the 0154004.DR and 0154002.DR?
The primary difference is the current rating: the 0154004.DR is a 4 A fuse, while the 0154002.DR is a 2 A fuse. Both share the same NANO2 154 series package, voltage rating, interrupting rating, and time-current characteristics.
Are the 0154004.DR and 0154002.DR interchangeable?
No. Although they share the same physical package and voltage ratings, they have different current ratings (4 A vs 2 A). Substitution must only be done after verifying the circuit's overcurrent protection requirements against the manufacturer datasheet.
What is the voltage rating of the 0154004.DR and 0154002.DR?
Both the 0154004.DR and 0154002.DR have a voltage rating of 125 V AC and 125 V DC, as specified in the Littelfuse NANO2 154 series datasheet.
What is the interrupting rating of the 0154004.DR and 0154002.DR?
Both fuses have an interrupting rating of 50 A at 125 V AC and 50 A at 125 V DC, according to the Littelfuse NANO2 154 series datasheet.
What package and mounting type do the 0154004.DR and 0154002.DR use?
Both the 0154004.DR and 0154002.DR are surface-mount fuses in the NANO2 package (also known as the 154 series), with a ceramic body and gold-plated caps, suitable for automated PCB assembly.
What are the typical applications for the 0154004.DR and 0154002.DR?
These fuses are typically used for overcurrent protection in consumer electronics, power supplies, battery packs, and industrial equipment where a compact surface-mount fuse with a 125 V rating is required. The 4 A version suits higher-current rails, while the 2 A version suits lower-current circuits.
Do the 0154004.DR and 0154002.DR have the same time-current characteristics?
Yes. Both the 0154004.DR and 0154002.DR are time-lag (slow-blow) fuses from the same NANO2 154 series, so they share the same time-current curve shape, though the absolute melting times differ due to the different current ratings.
What certifications do the 0154004.DR and 0154002.DR carry?
According to Littelfuse documentation, the NANO2 154 series fuses, including the 0154004.DR and 0154002.DR, are recognized under UL 248-14 and certified to CSA C22.2 No. 248.14. Always confirm current certification status on the manufacturer datasheet or official distributor listing.