Littelfuse 0278005.V Board Mount Fuse - Equivalent & Substitute Parts

Part Overview

The Littelfuse 0278005.V is a 5 A, 125 V AC/DC board mount fuse with fast blow response characteristics, designed for through-hole radial mounting in vertical orientation. This component is classified as obsolete, making identification of suitable substitute parts essential for ongoing design support and production continuity. The part operates across a temperature range of -55°C to 125°C and meets CSA, QPL, and UL approval standards.

Substiute Parts

0278005.V

Littelfuse Inc.In Stock: 7590278005.V Datasheet

Current PartRFQ

0273005.H

Littelfuse Inc.In Stock: 11830273005.H Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the Littelfuse 0278005.V is based on electrical and mechanical parameter alignment within the MICRO™ fuse series. The substitute part must satisfy the following critical parameters:

• Current Rating: 5 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, Radial, Can, Vertical (exact match required)
• Breaking Capacity: 10 kA @ Rated Voltage (exact match required)
• Melting I²t: 2.21 (exact match required)
• DC Cold Resistance: 0.0156 Ohms (exact match required)
• Approval Agencies: CSA, QPL, UL (exact match required)
• RoHS Compliance: ROHS3 Compliant (exact match required)

The Littelfuse 0273005.H meets all substitution criteria and is classified as an active product, providing design continuity for applications currently using the obsolete 0278005.V.

Parameter Comparison

Engineering Selection Recommendations

The Littelfuse 0273005.H is the manufacturer-recommended substitute for the obsolete 0278005.V. Both components maintain identical electrical specifications including current rating, voltage ratings, response time, breaking capacity, melting I²t, and DC cold resistance. Both parts carry equivalent approval certifications (CSA, QPL, UL) and ROHS3 compliance status.

The 0273005.H operates within a reduced temperature range (-55°C to 85°C) compared to the 0278005.V (-55°C to 125°C). Applications requiring operation above 85°C must evaluate this thermal limitation against circuit requirements. The substitute part features slightly larger physical dimensions (0.250" Dia x 0.350" H versus 0.235" Dia x 0.287" H), requiring verification of available board space during design transition.

The 0273005.H is actively manufactured and stocked, ensuring long-term availability and supply chain stability for new designs and production support.

Frequently Asked Questions (FAQ)

Q: Can the 0273005.H be used as a direct replacement for the 0278005.V in all applications?

A: The 0273005.H matches all critical electrical parameters and certifications. However, the reduced maximum operating temperature (85°C versus 125°C) and larger physical dimensions must be evaluated for specific applications. Verify that circuit operating temperatures remain below 85°C and that board layout accommodates the larger case size.

Q: What are the key differences between these two fuse models?

A: The primary differences are product status (obsolete versus active), operating temperature range (125°C versus 85°C maximum), and physical dimensions (0.235" Dia x 0.287" H versus 0.250" Dia x 0.350" H). All electrical specifications, response characteristics, and approval certifications are identical.

Q: Are there any compatibility concerns with PCB mounting?

A: The 0273005.H has larger dimensions than the 0278005.V. Verify that the PCB footprint and available board space accommodate the substitute part's 0.250" diameter and 0.350" height before implementation.

Q: Does the 0273005.H maintain the same safety certifications?

A: Yes. Both parts carry CSA, QPL, and UL approvals and are ROHS3 compliant, ensuring equivalent regulatory compliance for safety-critical applications.

Q: Why is the 0278005.V classified as obsolete?

A: The 0278005.V is no longer manufactured by Littelfuse Inc. The 0273005.H from the MICRO™ 273 series provides equivalent functionality and is the active product for ongoing design support.