SCHURTER 3404.0049.22 Equivalent & Substitute Parts

Part Overview

The SCHURTER 3404.0049.22 is a 125 mA, 125 V AC/DC surface mount board mount fuse in the OMF 125 series. This component is designed for circuit protection in applications requiring fast-blow response characteristics. The part is actively manufactured and widely stocked, with 650 units available in original packaging. Substitute parts are identified when equivalent electrical ratings, mechanical compatibility, and regulatory compliance align with the original specification.

Substiute Parts

3404.0049.22

SCHURTER Inc.In Stock: 6803404.0049.22 Datasheet

Current PartRFQ

0451.125MRL

Littelfuse Inc.In Stock: 309340451.125MRL Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SCHURTER 3404.0049.22 is determined by the following critical parameters:

• Current Rating: 125 mA (exact match required)
• Voltage Rating: 125 V AC and 125 V DC (exact match required)
• Response Time: Fast Blow (exact match required)
• Mounting Type: Surface Mount (exact match required)
• Fuse Type: Board Mount, Cartridge Style Excluded (exact match required)
• Operating Temperature Range: -55°C to 125°C (exact match required)
• RoHS Compliance: ROHS3 Compliant (exact match required)

The Littelfuse 0451.125MRL meets all critical electrical and mechanical parameters. While package geometry differs (2-SMD J-Lead versus 2-SMD Square End Block), both configurations are surface mount board mount fuses with identical electrical ratings and response characteristics. Physical dimensions vary slightly but remain within the 2-SMD form factor category.

Parameter Comparison

Engineering Selection Recommendations

Both the SCHURTER 3404.0049.22 and Littelfuse 0451.125MRL are active products with full regulatory compliance. The SCHURTER part carries cURus certification, while the Littelfuse part carries CSA and UL certifications. Selection between these parts should be based on:

• PCB layout constraints: The Littelfuse part is physically smaller (6.10mm x 2.69mm x 2.69mm versus 7.40mm x 3.10mm x 2.60mm), which may be advantageous in space-constrained designs.
• Certification requirements: Verify that the target application accepts CSA/UL or cURus approvals as specified in the design documentation.
• Breaking capacity requirements: The SCHURTER part provides 100A breaking capacity versus 50A for the Littelfuse part. Applications requiring higher breaking capacity must use the SCHURTER part.
• Melting I²t characteristics: The SCHURTER part has lower melting I²t (0.0011 versus 0.00286), resulting in faster thermal response. Applications with sensitive thermal requirements should verify compatibility with the substitute part's thermal profile.

Frequently Asked Questions (FAQ)

Q: Can the Littelfuse 0451.125MRL be used as a direct replacement for the SCHURTER 3404.0049.22?

A: The Littelfuse part meets all critical electrical parameters (125 mA, 125 V AC/DC, Fast Blow response). However, physical dimensions differ, and breaking capacity is lower (50A versus 100A). PCB layout compatibility and breaking capacity requirements must be verified before substitution.

Q: What is the difference between J-Lead and Square End Block package styles?

A: Both are 2-SMD surface mount configurations suitable for automated assembly. J-Lead (SCHURTER) and Square End Block (Littelfuse) differ in lead geometry and footprint. PCB design files must be verified to ensure compatibility with the selected package style.

Q: Are both parts RoHS compliant?

A: Yes, both the SCHURTER 3404.0049.22 and Littelfuse 0451.125MRL are ROHS3 Compliant and REACH Unaffected.

Q: Why does the Littelfuse part have higher melting I²t?

A: Melting I²t is a thermal characteristic that affects the speed of fuse response to overcurrent conditions. The SCHURTER part (0.0011) responds faster thermally than the Littelfuse part (0.00286). Applications with specific thermal response requirements must account for this difference.

Q: Which part should be selected for new designs?

A: Both parts are active products. Selection should be based on certification requirements, PCB layout constraints, breaking capacity needs, and thermal response characteristics specific to the application.