Littelfuse 37401250430 Board Mount Fuse - Equivalent & Substitute Parts

Part Overview

The Littelfuse 37401250430 is a 125 mA, 250 V AC/DC board mount fuse with slow blow response characteristics, designed for through-hole radial mounting in electronic assemblies. This TR5® 374 series fuse is actively produced and widely stocked. Substitute parts are identified to provide design flexibility, inventory alternatives, and sourcing options while maintaining electrical and mechanical compatibility within specified parameters.

Substiute Parts

37401250430

Littelfuse Inc.In Stock: 93137401250430 Datasheet

Current PartRFQ

37401250410

Littelfuse Inc.In Stock: 216437401250410 Datasheet

DirectRFQ

37201250411

Littelfuse Inc.In Stock: 387837201250411 Datasheet

Parametric EquivalentRFQ

0034.7106

SCHURTER Inc.In Stock: 18610034.7106 Datasheet

DirectRFQ

0034.7306

SCHURTER Inc.In Stock: 31380034.7306 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 37401250430 are classified based on strict electrical and mechanical parameter alignment:

Critical Parameters for Substitution:

• Current Rating: 125 mA (exact match required)
• Voltage Rating (AC): 250 V (exact match required)
• Response Time: Slow Blow (exact match required)
• Mounting Type: Through Hole (exact match required)
• Package / Case: Radial, Can, Vertical (exact match required)
• Operating Temperature Range: -40°C ~ 85°C (exact match required)

Acceptable Variation Parameters:

• Breaking Capacity @ Rated Voltage: 35A to 50A
• Melting I²t: 0.044 to 0.1094
• DC Cold Resistance: 1.35 to 2.9 Ohms
• Physical Dimensions: 0.335" Dia x 0.315" H to 0.335" Dia x 0.335" H (8.50mm x 8.00mm to 8.50mm x 8.50mm)
• Manufacturer: Littelfuse Inc. or SCHURTER Inc.
• Packaging Format: Bulk or Cut Tape (CT)

Parameter Comparison

Engineering Selection Recommendations

Direct Equivalent (Highest Compatibility): Part number 37401250410 (Littelfuse Inc., TR5® 374 series) is a direct manufacturer equivalent with identical electrical specifications, breaking capacity, melting I²t, and physical dimensions. This part is recommended as the primary substitute when 37401250430 is unavailable.

Parametric Equivalent (Series Variant): Part number 37201250411 (Littelfuse Inc., TR5® 372 series) meets all critical electrical parameters but features a lower breaking capacity (35A versus 50A) and higher melting I²t (0.1094 versus 0.044). This part is suitable for applications where the reduced breaking capacity is acceptable within circuit design margins.

Cross-Manufacturer Alternatives: Part numbers 0034.7106 and 0034.7306 (SCHURTER Inc., MSTU 250 series) provide equivalent electrical performance with 50A breaking capacity. Physical dimensions are slightly larger (8.50mm x 8.50mm versus 8.50mm x 8.00mm). These parts are available in both Bulk (0034.7106) and Cut Tape (0034.7306) packaging formats. Verify PCB footprint clearance before selection.

Product Status & Compliance: All substitute parts maintain Active product status and ROHS3 compliance. Littelfuse parts carry CSA and cULus approvals; SCHURTER parts carry cULus approval. Selection should align with circuit certification requirements.

Frequently Asked Questions (FAQ)

Q: Can 37401250410 be used as a direct replacement for 37401250430? A: Yes. Both parts are Littelfuse TR5® 374 series with identical current rating (125 mA), voltage rating (250 V), response time (Slow Blow), breaking capacity (50A), and physical dimensions (8.50mm x 8.00mm). They are electrically and mechanically interchangeable.

Q: What is the difference between 37401250430 and 37201250411? A: Both parts share the same current rating (125 mA), voltage rating (250 V), and response time (Slow Blow). However, 37201250411 belongs to the TR5® 372 series and has a lower breaking capacity (35A versus 50A) and higher melting I²t (0.1094 versus 0.044). Use 37201250411 only if circuit design accommodates the reduced breaking capacity.

Q: Are SCHURTER parts (0034.7106 and 0034.7306) compatible with Littelfuse designs? A: SCHURTER parts 0034.7106 and 0034.7306 match all critical electrical parameters and breaking capacity (50A). Physical dimensions are slightly larger (8.50mm x 8.50mm versus 8.50mm x 8.00mm). Verify PCB layout and mounting clearance before substitution. Both parts are cULus approved.

Q: What is the difference between 0034.7106 and 0034.7306? A: Both parts are electrically and mechanically identical SCHURTER MSTU 250 series fuses. The difference is packaging format: 0034.7106 is supplied in Bulk packaging, while 0034.7306 is supplied in Cut Tape (CT) packaging. Select based on assembly process requirements.

Q: Can I use a substitute part with lower breaking capacity in my circuit? A: Breaking capacity determines the maximum fault current the fuse can safely interrupt. Use a substitute with lower breaking capacity only if your circuit design ensures fault currents remain below the substitute part's breaking capacity rating. Consult circuit protection analysis before substitution.

Q: Are all substitute parts RoHS3 compliant? A: Yes. All listed substitute parts (37401250410, 37201250411, 0034.7106, 0034.7306) are ROHS3 compliant and REACH unaffected, matching the compliance status of the main part 37401250430.