Equivalent & Substitute Parts for Bel Fuse Inc. 5MF 2.5

Part Overview

The Bel Fuse Inc. 5MF 2.5 is a 2.5 A, 250 V AC/DC fast-blow glass cartridge fuse in a 5mm x 20mm package format. This part is classified as obsolete, with 1,097 units available in current inventory. Due to its obsolete status, identifying equivalent and substitute components is essential for system maintenance, repair, and new design implementations where this fuse type is specified.

Substiute Parts

5MF 2.5

Bel Fuse Inc.In Stock: 11145MF 2.5 Datasheet

Current PartRFQ

5MF 2.5-R

Bel Fuse Inc.In Stock: 235925MF 2.5-R Datasheet

DirectRFQ

5SF 2.5-R

Bel Fuse Inc.In Stock: 27815SF 2.5-R Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the 5MF 2.5 is determined by strict equivalence across the following critical parameters:

• Current Rating: 2.5 A (exact match required)
• Voltage Rating: 250 V AC (exact match required)
• Package / Case: 5mm x 20mm (exact match required)
• Fuse Type: Cartridge, Glass (exact match required)
• Response Time: Fast Blow (exact match required)
• Mounting Type: Requires Holder (exact match required)

Two substitute parts meet these criteria: the 5MF 2.5-R (direct manufacturer upgrade) and the 5SF 2.5-R (parametric equivalent from the same manufacturer). Both maintain identical electrical and mechanical specifications while offering improved availability and compliance status.

Parameter Comparison

Engineering Selection Recommendations

The 5MF 2.5-R is the primary direct substitute for the obsolete 5MF 2.5. Both parts share identical electrical and mechanical specifications, with the 5MF 2.5-R offering active product status, significantly higher inventory availability (23,563 units), and ROHS3 compliance. The 5MF 2.5-R maintains the same breaking capacity (200 A) and melting I²t (7.6) as the original part, ensuring equivalent circuit protection performance.

The 5SF 2.5-R serves as a parametric equivalent when the 5MF 2.5-R is unavailable. While it maintains identical current, voltage, package, and response characteristics, the 5SF 2.5-R exhibits a lower breaking capacity (35 A versus 200 A) and higher melting I²t (10 versus 7.6). The 5SF 2.5-R also provides broader international certifications (CCC, IMQ, SEMKO, VDE in addition to CE, CSA, cURus) and ROHS3 compliance. Selection between these two substitutes depends on circuit protection requirements and breaking capacity specifications for the target application.

Frequently Asked Questions (FAQ)

Q: Can the 5MF 2.5-R be used as a direct replacement for the 5MF 2.5?

A: Yes. The 5MF 2.5-R is a direct substitute with identical current rating (2.5 A), voltage rating (250 V), package format (5mm x 20mm), response time (fast blow), and breaking capacity (200 A). Both require the same holder for installation.

Q: What is the difference between the 5MF 2.5-R and 5SF 2.5-R?

A: Both parts share identical electrical and mechanical core specifications (2.5 A, 250 V, 5mm x 20mm, fast blow). The primary differences are: the 5MF 2.5-R maintains a breaking capacity of 200 A and melting I²t of 7.6, while the 5SF 2.5-R has a breaking capacity of 35 A and melting I²t of 10. The 5SF 2.5-R carries additional international certifications (CCC, IMQ, SEMKO, VDE).

Q: Why is the original 5MF 2.5 marked as obsolete?

A: The 5MF 2.5 is classified as obsolete by the manufacturer. The 5MF 2.5-R represents the active product line continuation with improved compliance and availability.

Q: Are there any compatibility concerns when substituting these parts?

A: No compatibility concerns exist for mechanical or electrical installation. All three parts use identical 5mm x 20mm cartridge format and require the same holder. Verify that your circuit protection requirements align with the breaking capacity specifications of your selected substitute.

Q: Which substitute should I select for new designs?

A: For new designs, the 5MF 2.5-R is recommended due to its active status, higher inventory availability, and identical performance characteristics to the original 5MF 2.5. The 5SF 2.5-R is suitable when the 5MF 2.5-R is unavailable or when the lower breaking capacity (35 A) meets application requirements.

Q: Are both substitutes RoHS compliant?

A: Yes. Both the 5MF 2.5-R and 5SF 2.5-R are ROHS3 compliant, whereas the original 5MF 2.5 is RoHS non-compliant.