Littelfuse 0452.750NRL Surface Mount Board Mount Fuse Equivalent & Substitute Parts

Part Overview

The Littelfuse 0452.750NRL is a 750 mA, 125 V AC/DC surface mount board mount fuse in the NANO²® 452 series. This slow blow fuse is designed for circuit protection in applications requiring 2-SMD, square end block packaging. The part is active in production status with full RoHS3 compliance and CSA, UR approvals. Equivalent and substitute parts are identified to support procurement flexibility, inventory management, and design continuity across compatible NANO²® series fuses with identical electrical and mechanical specifications.

Substiute Parts

0452.750NRL

Littelfuse Inc.In Stock: 10550452.750NRL Datasheet

Current PartRFQ

0449.750MR

Littelfuse Inc.In Stock: 17420449.750MR Datasheet

Parametric EquivalentRFQ

0452.750MRL

Littelfuse Inc.In Stock: 993500452.750MRL Datasheet

Parametric EquivalentRFQ

0454.750MR

LittelfuseIn Stock: 52890454.750MR Datasheet

Parametric EquivalentRFQ

0454.750NR

Littelfuse Inc.In Stock: 10310454.750NR Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 0452.750NRL is determined by strict equivalence across the following critical parameters:

• Current Rating: 750 mA (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)
• Breaking Capacity @ Rated Voltage: 50 A (exact match required)
• Physical Dimensions: 0.240" L x 0.106" W x 0.106" H (exact match required)
• Operating Temperature Range: -55°C ~ 125°C (exact match required)
• Compliance: RoHS3 Compliant, MSL 1 (exact match required)

All identified substitute parts meet these criteria and are members of the Littelfuse NANO²® fuse family. Substitutes differ only in series designation (449, 452, 454) and minor variations in DC cold resistance and melting I²t characteristics, which remain within acceptable operational parameters for this fuse category.

Parameter Comparison

Engineering Selection Recommendations

All substitute parts listed are active production components with full RoHS3 compliance and regulatory approvals suitable for circuit protection applications. The 0452.750NRL and 0452.750MRL are both NANO²® 452 series parts with identical electrical characteristics, DC cold resistance, and melting I²t values, making them direct functional equivalents. The 0454.750MR and 0454.750NR are NANO²® 454 series alternatives with equivalent performance parameters and CSA, UL certifications. The 0449.750MR is a NANO²® 449 series option with cULus approval and slightly elevated DC cold resistance (0.408 Ohms versus 0.36 Ohms) and lower melting I²t (0.847 versus 0.904), which remains within acceptable operational tolerance for this fuse category.

Selection among these parts should be based on inventory availability, lead time requirements, and specific regulatory certification requirements for the end application. All parts are packaged in Tape & Reel format and maintain identical physical dimensions and surface mount compatibility.

Frequently Asked Questions (FAQ)

Q: Can the 0449.750MR be used as a direct replacement for the 0452.750NRL?

A: The 0449.750MR meets all critical electrical and mechanical parameters: 750 mA current rating, 125 V AC/DC voltage rating, slow blow response, surface mount configuration, and 2-SMD square end block package. The DC cold resistance is 0.408 Ohms (versus 0.36 Ohms) and melting I²t is 0.847 (versus 0.904), both within acceptable operational parameters for this fuse category. The part carries cULus approval. Substitution is electrically and mechanically valid.

Q: What is the difference between the 0452.750NRL and 0452.750MRL?

A: Both parts are NANO²® 452 series fuses with identical electrical specifications, current rating, voltage rating, response time, and DC cold resistance (0.36 Ohms). The primary difference is packaging designation (NRL versus MRL). Both are active production parts with CSA, UR approvals and RoHS3 compliance.

Q: Are all substitute parts compatible with the same PCB footprint?

A: Yes. All substitute parts share identical physical dimensions of 0.240" L x 0.106" W x 0.106" H (6.10mm x 2.69mm x 2.69mm) and use the same 2-SMD, square end block package configuration, ensuring PCB footprint compatibility.

Q: What regulatory certifications apply to these fuses?

A: The 0452.750NRL carries CSA and UR approvals. Substitute parts carry CSA, UL, or cULus certifications. All parts are RoHS3 compliant and REACH unaffected. Specific certification requirements should be verified against end-application regulatory standards.

Q: Can these fuses be used in both AC and DC circuits?

A: Yes. All parts are rated for 125 V AC and 125 V DC operation, supporting both alternating and direct current applications within the specified voltage and current parameters.

Q: What is the Moisture Sensitivity Level (MSL) for these parts?

A: All parts carry MSL 1 (Unlimited), indicating no moisture sensitivity restrictions and unlimited shelf life under standard storage conditions.