Littelfuse 0452004.MR Surface Mount Board Mount Fuse Equivalent & Substitute Parts

Part Overview

The Littelfuse 0452004.MR is a 4 A, 125 V AC/DC surface mount board mount fuse in the NANO²® 452 series with a 2-SMD square end block package. This part is classified as obsolete. Equivalent and substitute parts are available from the active NANO²® product lines (449, 452, and 454 series) that maintain identical electrical and mechanical specifications, offering continued design support and improved compliance status for new applications and production continuity.

Substiute Parts

0452004.MR

Littelfuse Inc.In Stock: 53530452004.MR Datasheet

Current PartRFQ

0449004.MR

Littelfuse Inc.In Stock: 28000449004.MR Datasheet

Parametric EquivalentRFQ

0452004.MRL

Littelfuse Inc.In Stock: 430300452004.MRL Datasheet

Parametric EquivalentRFQ

0452004.NRL

Littelfuse Inc.In Stock: 307040452004.NRL Datasheet

Parametric EquivalentRFQ

0454004.MR

Littelfuse Inc.In Stock: 302880454004.MR Datasheet

Parametric EquivalentRFQ

0454004.NR

LittelfuseIn Stock: 7650454004.NR Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 0452004.MR is determined by strict equivalence across the following critical parameters:

• Current Rating: 4 A (exact match required)
• Voltage Rating: 125 V AC and 125 V DC (exact match required)
• Response Time: Slow Blow (exact match required)
• Mounting Type: Surface Mount (exact match required)
• Package / Case: 2-SMD, Square End Block (exact match required)
• Physical Dimensions: 0.240" L x 0.106" W x 0.106" H (exact match required)
• Breaking Capacity: 50 A (exact match required)
• Operating Temperature Range: -55°C ~ 125°C (exact match required)

All substitute parts listed maintain these specifications. Differences in series designation (NANO²® 449, 452, 454), packaging format (Cut Tape & Digi-Reel®, Tape & Reel), and compliance status do not affect electrical or mechanical compatibility.

Parameter Comparison

Engineering Selection Recommendations

For Obsolete Part Replacement: The 0452004.MR is obsolete. Direct functional replacements with active product status are 0452004.MRL and 0452004.NRL, both from the same NANO²® 452 series. These parts maintain identical electrical characteristics (Melting I²t: 34.4, DC Cold Resistance: 0.0186 Ohms) and are ROHS3 compliant.

For New Designs and Production Continuity: Active alternatives from NANO²® 449 and 454 series (0449004.MR, 0454004.MR, 0454004.NR) provide equivalent electrical and mechanical performance with improved compliance. The 0449004.MR exhibits higher Melting I²t (40.8) and DC Cold Resistance (0.0227 Ohms) while maintaining all critical electrical ratings and approvals.

Packaging Considerations:

• Cut Tape & Digi-Reel® format (0452004.MRL, 0454004.MR): Suitable for automated assembly and high-volume production
• Tape & Reel format (0449004.MR, 0452004.NRL, 0454004.NR): Standard for pick-and-place equipment
• Bulk format (0452004.MR): Original obsolete packaging

Compliance Status: All active substitute parts are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements. The original 0452004.MR is RoHS non-compliant.

Frequently Asked Questions (FAQ)

Q: Can I directly replace 0452004.MR with any of the listed substitute parts? A: Yes. All listed parts maintain identical current rating (4 A), voltage rating (125 V AC/DC), response time (Slow Blow), mounting type (Surface Mount), package type (2-SMD, Square End Block), and physical dimensions (0.240" L x 0.106" W x 0.106" H). Electrical and mechanical compatibility is assured.

Q: What is the difference between 0452004.MRL and 0452004.NRL? A: Both are from the NANO²® 452 series with identical electrical specifications. The difference is packaging format: 0452004.MRL uses Cut Tape & Digi-Reel® format, while 0452004.NRL uses Tape & Reel format. Selection depends on assembly equipment compatibility.

Q: Why does 0449004.MR have different Melting I²t and DC Cold Resistance values? A: The 0449004.MR is from the NANO²® 449 series, which has different internal design characteristics. Despite these parameter differences, it maintains the same 4 A current rating, 125 V voltage rating, Slow Blow response, and physical package, making it electrically and mechanically compatible for this application.

Q: Is the 0452004.MR still available? A: The 0452004.MR is classified as obsolete. However, 5,300 pieces are reported in stock. For new designs and long-term production, active alternatives (0452004.MRL, 0452004.NRL, 0449004.MR, 0454004.MR, 0454004.NR) are recommended.

Q: Which substitute part should I choose for automated assembly? A: For automated pick-and-place assembly, choose parts with Cut Tape & Digi-Reel® or Tape & Reel packaging: 0452004.MRL, 0449004.MR, 0452004.NRL, 0454004.MR, or 0454004.NR. Verify your equipment's compatibility with the specific tape format.

Q: Are all substitute parts ROHS3 compliant? A: Yes. All active substitute parts (0449004.MR, 0452004.MRL, 0452004.NRL, 0454004.MR, 0454004.NR) are ROHS3 compliant and REACH unaffected. The original 0452004.MR is RoHS non-compliant.