Littelfuse 0274.250V Board Mount Fuse Equivalent & Substitute Parts

Part Overview

The Littelfuse 0274.250V is a 250 mA, 125 V AC/DC board mount fuse in the MICRO™ 274 series, designed for through-hole radial mounting in vertical orientation. This fast-blow fuse provides circuit protection in applications requiring 10 kA breaking capacity at rated voltage. The part is active in production with full compliance to CSA, QPL, and UL standards. Substitute parts may be required due to inventory availability, design revisions across MICRO™ series generations, or specific application requirements within the same electrical and mechanical specifications.

Substiute Parts

0274.250V

Littelfuse Inc.In Stock: 11940274.250V Datasheet

Current PartRFQ

0273.250H

Littelfuse Inc.In Stock: 15970273.250H Datasheet

Parametric EquivalentRFQ

0273.250V

Littelfuse Inc.In Stock: 10510273.250V Datasheet

Parametric EquivalentRFQ

0279.250V

Littelfuse Inc.In Stock: 8840279.250V Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the Littelfuse 0274.250V is permissible with the following parts based on identical electrical and mechanical parameters:

Substitution Criteria:

• Current Rating: 250 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: Through Hole (exact match required)
• Package / Case: Radial, Can, Vertical (exact match required)
• Breaking Capacity: 10 kA @ Rated Voltage (exact match required)
• Size / Dimension: 0.250" Dia x 0.350" H (exact match required)
• DC Cold Resistance: 1.75 Ohms (exact match required)
• Melting I²t: 0.0064 (exact match required)
• Approval Agencies: CSA, QPL, UL (exact match required)
• RoHS Compliance: ROHS3 Compliant (exact match required)

All substitute parts listed below meet these criteria and belong to different generations within the Littelfuse MICRO™ fuse series (273, 274, and 279). Series designation does not affect electrical or mechanical compatibility when all parameters are identical.

Parameter Comparison

Engineering Selection Recommendations

All substitute parts (0273.250H, 0273.250V, 0279.250V) are functionally equivalent to the primary part 0274.250V based on identical electrical and mechanical specifications. Selection among these parts should be based on:

Product Status: All parts maintain active production status with full CSA, QPL, and UL certifications, ensuring continued availability and regulatory compliance.

Compliance & Certifications: All parts carry identical approval designations (CSA, QPL, UL) and maintain ROHS3 compliance with REACH unaffected status, meeting environmental and regulatory requirements across all markets.

Inventory Availability: Current stock levels vary across part numbers. Selection may be driven by procurement lead times and inventory position at the time of component sourcing.

Series Designation: The MICRO™ series designation (273, 274, 279) reflects internal Littelfuse product line organization and does not impact electrical or mechanical performance when all rated parameters are identical.

Frequently Asked Questions (FAQ)

Q: Can the 0273.250H, 0273.250V, and 0279.250V be used interchangeably with the 0274.250V?

A: Yes. All parts share identical electrical ratings (250 mA, 125 V AC/DC, fast-blow response), mechanical dimensions (0.250" Dia x 0.350" H), breaking capacity (10 kA), and approval certifications (CSA, QPL, UL). Direct substitution is permissible in circuit designs without modification.

Q: What determines whether a fuse can substitute for the 0274.250V?

A: Substitution requires exact matching of current rating, voltage rating (AC and DC), response time, mounting type, package configuration, breaking capacity, physical dimensions, DC cold resistance, melting I²t value, and approval agency certifications. Any deviation in these parameters disqualifies a part from substitution.

Q: Are there differences in operating temperature ranges among these parts?

A: The main part 0274.250V does not specify an operating temperature range. The substitute parts 0273.250H, 0273.250V, and 0279.250V specify -55°C ~ 85°C. When operating temperature specification is critical to the application, the substitute parts with defined temperature range should be selected.

Q: Do all these parts have the same through-hole mounting footprint?

A: Yes. All parts are specified as through-hole radial, can, vertical mount with identical dimensions of 0.250" Dia x 0.350" H (6.35 mm x 8.89 mm), ensuring PCB footprint compatibility without layout modification.

Q: What is the significance of the MICRO™ series designation?

A: The MICRO™ series designation (273, 274, 279) identifies the product line within Littelfuse's fuse portfolio. When electrical and mechanical parameters are identical, series designation does not affect functional compatibility or performance in circuit applications.