Littelfuse 20105000301 Glass Cartridge Fuse — Equivalent & Substitute Parts

Part Overview

The Littelfuse 20105000301 is a 500 mA, 250 V AC/DC glass cartridge fuse with a 5mm × 20mm form factor, designed for circuit protection in industrial and commercial applications. This fuse operates with medium blow response characteristics and requires a compatible holder for installation. The part is active in production and widely stocked, making it suitable for new designs and replacement applications. Alternative equivalent parts may be required due to supply chain considerations, design revisions, or regional availability constraints.

Substiute Parts

20105000301

LittelfuseIn Stock: 107820105000301 Datasheet

Current PartRFQ

20105000001

Littelfuse Inc.In Stock: 302220105000001 Datasheet

Parametric EquivalentRFQ

20105000021P

Littelfuse Inc.In Stock: 96220105000021P Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the Littelfuse 20105000301 is determined by strict equivalence across the following critical parameters:

• Current Rating: 500 mA (exact match required)
• Voltage Rating (AC): 250 V (exact match required)
• Fuse Type: Cartridge, Glass (exact match required)
• Package / Case: 5mm × 20mm (exact match required)
• Response Time: Medium Blow (exact match required)
• Breaking Capacity @ Rated Voltage: 80 A (exact match required)
• Melting I²t: 0.35 (exact match required)
• Approval Agency: cULus (exact match required)
• Operating Temperature Range: −25°C to 70°C (exact match required)
• RoHS Status: ROHS3 Compliant (exact match required)

All identified substitute parts meet these criteria without deviation. Substitutes differ only in series designation (201 vs. 201P) and inventory availability, which do not affect electrical or mechanical performance.

Parameter Comparison

Engineering Selection Recommendations

All three parts—20105000301, 20105000001, and 20105000021P—are functionally equivalent for circuit protection applications requiring 500 mA, 250 V AC/DC protection in a 5mm × 20mm glass cartridge format. Each part carries active product status and cULus approval, confirming compliance with applicable safety standards.

Selection between these parts should be based on:

• Inventory availability and lead time requirements
• Series compatibility with existing designs (201 vs. 201P)
• Supply chain logistics and regional sourcing preferences

No electrical or mechanical performance differences exist between these parts. All are ROHS3 compliant and operate across the identical temperature range.

Frequently Asked Questions (FAQ)

Q: Can 20105000001 be used as a direct replacement for 20105000301?

A: Yes. Both parts are electrically and mechanically identical, differing only in series designation (201 vs. 201P). Direct substitution is permissible without circuit redesign.

Q: What is the difference between the 201 and 201P series?

A: Series designation does not affect electrical performance, current rating, voltage rating, or physical dimensions. Both series meet identical safety certifications and operating specifications.

Q: Are all three parts compatible with the same fuse holder?

A: Yes. All three parts share the identical 5mm × 20mm form factor and require the same holder type. Physical installation is interchangeable.

Q: Do these fuses require any special handling or storage conditions?

A: All parts carry Moisture Sensitivity Level (MSL) 1, indicating unlimited shelf life without special moisture control measures.

Q: What is the breaking capacity specification, and why does it matter?

A: Breaking capacity of 80 A at rated voltage indicates the maximum fault current the fuse can safely interrupt without rupturing or creating a hazard. This specification must match the circuit's maximum available fault current.

Q: Are these parts suitable for both AC and DC applications?

A: Yes. All parts are rated for 250 V AC/DC operation, making them suitable for both alternating and direct current circuits within the specified voltage range.