Littelfuse 0275004.M Equivalent & Substitute Parts

Part Overview

The Littelfuse 0275004.M is a 4 A, 125 V AC/DC board mount axial fuse with fast blow response time, designed for through-hole mounting applications. This component is classified as obsolete, making identification of suitable substitute parts essential for ongoing system support and new design implementations. The PICO® 275 series fuse provides protection in low-voltage DC and AC circuits requiring fast-acting overcurrent response.

Substiute Parts

0275004.M

Littelfuse Inc.In Stock: 11260275004.M Datasheet

Current PartRFQ

0251004.MXL

Littelfuse Inc.In Stock: 46500251004.MXL Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 0275004.M is determined by strict equivalence across the following electrical and mechanical parameters:

• Current Rating: 4 A (exact match required)
• Voltage Rating: 125 V AC and 125 V DC (exact match required)
• Response Time: Fast Blow (exact match required)
• Mounting Type: Through Hole (exact match required)
• Fuse Type: Board Mount, Axial configuration (exact match required)
• Operating Temperature Range: -55°C to 125°C (exact match required)

The Littelfuse 0251004.MXL meets all substitution criteria as a direct equivalent. This part belongs to the PICO® II 251 series and maintains identical electrical ratings and mechanical form factor compatibility with the obsolete 0275004.M.

Parameter Comparison

Engineering Selection Recommendations

The Littelfuse 0251004.MXL is the direct substitute for the obsolete 0275004.M. Selection of this substitute part is based on:

• Electrical Equivalence: Identical current and voltage ratings (4 A, 125 V AC/DC) with matching fast blow response time
• Mechanical Compatibility: Through-hole axial mounting configuration with compatible form factor
• Product Status: The 0251004.MXL is an active product with full manufacturing support, addressing the obsolescence of the original part
• Regulatory Compliance: The substitute part carries expanded approval certifications (CCC, CSA, cURus, PSE, TUV) compared to the original UL-only approval, and achieves ROHS3 compliance versus the non-compliant status of the 0275004.M
• Availability: The 0251004.MXL maintains higher inventory levels, supporting production continuity

Physical dimension variation exists between the two parts (diameter: 0.093" vs. 0.110"), requiring verification of PCB footprint clearance during board-level integration.

Frequently Asked Questions (FAQ)

Q: Can the 0251004.MXL be used as a direct replacement for the 0275004.M in existing designs?

A: Yes, the 0251004.MXL provides electrical and functional equivalence. However, the substitute part has a larger diameter (0.110" vs. 0.093"), requiring confirmation that the PCB mounting hole and surrounding component clearance accommodate this dimension change.

Q: What is the difference between the PICO® 275 and PICO® II 251 series?

A: Both series are Littelfuse board mount axial fuses. The PICO® II 251 represents a newer product line with enhanced regulatory certifications and RoHS3 compliance. Electrical performance and response characteristics remain equivalent for the specified ratings.

Q: Are there any compliance differences between these parts?

A: The 0275004.M is RoHS non-compliant, while the 0251004.MXL achieves ROHS3 compliance. The substitute part also carries broader international approvals (CCC, CSA, cURus, PSE, TUV) versus the original part's UL-only certification.

Q: What is the breaking capacity of the substitute part?

A: The 0251004.MXL has a breaking capacity of 50 A AC and 300 A DC at rated voltage, with a melting I²t value of 2.45.

Q: Are there packaging differences?

A: The 0275004.M packaging specification is listed as "-" (not specified), while the 0251004.MXL is supplied in bulk packaging. This does not affect functional equivalence.