Bel Fuse Inc. 5MFP 2.5 Equivalent & Substitute Parts

Part Overview

The Bel Fuse Inc. 5MFP 2.5 is a 2.5 A 250 V AC/DC fast-blow glass cartridge fuse with a 5mm x 20mm axial form factor and through-hole mounting. This part is classified as obsolete, making identification of equivalent and substitute components essential for ongoing system support and procurement planning. Substitute parts must maintain identical electrical ratings, mechanical dimensions, and functional characteristics to ensure direct compatibility in existing circuit designs.

Substiute Parts

5MFP 2.5

Bel Fuse Inc.In Stock: 9305MFP 2.5 Datasheet

Current PartRFQ

5MFP 2.5-R

Bel Fuse Inc.In Stock: 20705MFP 2.5-R Datasheet

DirectRFQ

5SFP 2.5-R

Bel Fuse Inc.In Stock: 25095SFP 2.5-R Datasheet

Parametric EquivalentRFQ

021702.5MXEP

Littelfuse Inc.In Stock: 2287021702.5MXEP Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 5MFP 2.5 are classified based on electrical and mechanical parameter alignment:

Direct Manufacturer Substitute (5MFP 2.5-R): Identical current rating (2.5 A), voltage rating (250 V), fuse type (cartridge glass), response time (fast blow), package dimensions (5mm x 20mm), and mounting type (through hole). This part is manufactured by the same supplier (Bel Fuse Inc.) and maintains the same series designation. The primary distinction is product status: 5MFP 2.5-R is active, whereas the original 5MFP 2.5 is obsolete.

Parametric Equivalent (5SFP 2.5-R): Matches all critical electrical parameters (2.5 A, 250 V, fast blow, through hole) and mechanical form factor (5mm x 20mm). Manufactured by Bel Fuse Inc. under a different series (5SFP). Differences include breaking capacity (35 A vs. 200 A) and melting I²t (10 vs. 7.6), which reflect different internal construction but do not affect circuit-level compatibility for standard applications.

Similar Cross-Manufacturer Substitute (021702.5MXEP): Manufactured by Littelfuse Inc. (series 217). Maintains identical electrical ratings (2.5 A, 250 V, fast blow) and equivalent mechanical form factor (5.80mm x 22.50mm, compared to 5.50mm x 21.00mm). Slight dimensional variance and different breaking capacity (35 A) are within acceptable tolerance for through-hole mounting applications. Broader certification portfolio (BSI, CE, CCC, CSA, KC, PSE, SEMKO, UR, VDE) provides enhanced regulatory coverage.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Same Manufacturer, Same Series): Select 5MFP 2.5-R. This part is the active production equivalent of the obsolete 5MFP 2.5, manufactured by Bel Fuse Inc. under the same 5MFP series. It maintains identical electrical and mechanical specifications, ensuring seamless integration into existing designs. The part is ROHS3 compliant and carries expanded certifications (cULus added). Inventory availability is higher (1977 pcs vs. 830 pcs).

For Parametric Equivalence (Same Manufacturer, Different Series): Select 5SFP 2.5-R. This Bel Fuse Inc. part meets all critical electrical requirements and maintains the same form factor. The reduced breaking capacity (35 A vs. 200 A) and increased melting I²t (10 vs. 7.6) reflect different internal fuse element design but do not compromise functionality in standard circuit protection applications. This option provides the broadest certification coverage (CCC, CE, CSA, cULus, IMQ, SEMKO, VDE) and highest inventory (2400 pcs).

For Cross-Manufacturer Substitution: Select 021702.5MXEP (Littelfuse Inc., series 217). This part maintains identical electrical ratings and equivalent mechanical form factor. The dimensional variance (5.80mm x 22.50mm vs. 5.50mm x 21.00mm) is within acceptable tolerance for through-hole mounting. This option offers the most comprehensive regulatory certifications (BSI, CE, CCC, CSA, KC, PSE, SEMKO, UR, VDE) and is suitable for applications requiring enhanced international compliance documentation.

Frequently Asked Questions (FAQ)

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

A: Yes. The 5MFP 2.5-R is the active production equivalent manufactured by Bel Fuse Inc. It maintains identical current rating (2.5 A), voltage rating (250 V), fuse type (cartridge glass), response time (fast blow), package dimensions (5mm x 20mm), and mounting type (through hole). The primary difference is product status and RoHS compliance.

Q: What is the difference between 5MFP 2.5-R and 5SFP 2.5-R?

A: Both parts are manufactured by Bel Fuse Inc. and share identical electrical ratings and form factor. The 5SFP 2.5-R has a lower breaking capacity (35 A vs. 200 A) and higher melting I²t (10 vs. 7.6), indicating different internal fuse element construction. For standard circuit protection applications, both are functionally equivalent. The 5SFP 2.5-R offers broader international certifications.

Q: Can the Littelfuse 021702.5MXEP be used in place of the Bel Fuse 5MFP 2.5?

A: Yes, with dimensional consideration. The 021702.5MXEP maintains identical electrical ratings (2.5 A, 250 V, fast blow) and equivalent through-hole mounting. The package dimensions are slightly larger (5.80mm x 22.50mm vs. 5.50mm x 21.00mm), which is within acceptable tolerance for standard PCB-mounted fuse holders. Verify mechanical fit in your specific application before deployment.

Q: Are all substitute parts RoHS compliant?

A: The original 5MFP 2.5 is RoHS non-compliant. All three substitute parts (5MFP 2.5-R, 5SFP 2.5-R, and 021702.5MXEP) are ROHS3 compliant, meeting current environmental regulations.

Q: Which substitute part has the best regulatory certification coverage?

A: The Littelfuse 021702.5MXEP (series 217) carries the broadest certification portfolio: BSI, CE, CCC, CSA, KC, PSE, SEMKO, UR, and VDE. This part is recommended for applications requiring comprehensive international compliance documentation or deployment in multiple regulatory jurisdictions.

Q: What is the significance of breaking capacity differences?

A: Breaking capacity indicates the maximum fault current a fuse can safely interrupt. The 5MFP 2.5 and 5MFP 2.5-R have 200 A breaking capacity, while 5SFP 2.5-R and 021702.5MXEP have 35 A. For standard circuit protection applications operating within normal design parameters, the lower breaking capacity is sufficient. Verify your circuit's maximum fault current against the fuse's breaking capacity specification.

Q: Can these parts be used interchangeably in the same circuit?

A: Yes, for standard applications. All substitute parts maintain the same current rating (2.5 A), voltage rating (250 V), response time (fast blow), and operating temperature range (-55°C ~ 125°C). Verify mechanical fit (package dimensions) in your specific fuse holder before substitution.