Littelfuse 02371.25M Glass Cartridge Fuse Equivalent & Substitute Parts

Part Overview

The Littelfuse 02371.25M is a 1.25 A, 125 V AC/DC glass cartridge fuse with a 5mm x 20mm form factor, designed for use in fuse holders. This part is classified as obsolete and has been superseded by active production alternatives from Littelfuse that maintain identical electrical and mechanical specifications. Locating substitute parts is necessary due to the discontinued status of the original component.

Substiute Parts

02371.25M

Littelfuse Inc.In Stock: 111402371.25M Datasheet

Current PartRFQ

02331.25MXP

Littelfuse Inc.In Stock: 179202331.25MXP Datasheet

MFR RecommendedRFQ

02321.25MX125P

Littelfuse Inc.In Stock: 79002321.25MX125P Datasheet

Parametric EquivalentRFQ

02331.25MXBP

Littelfuse Inc.In Stock: 82202331.25MXBP Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 02371.25M are qualified based on strict equivalence of the following parameters: current rating (1.25 A), voltage rating (125 V AC), fuse type (cartridge glass), physical dimensions (5mm x 20mm), response time (medium blow), and breaking capacity (10 kA). All substitute parts listed maintain these core electrical and mechanical specifications, ensuring direct functional replacement in applications designed for the original component.

Parameter Comparison

Engineering Selection Recommendations

All three substitute parts (02331.25MXP, 02321.25MX125P, and 02331.25MXBP) are active production components from Littelfuse that provide direct electrical and mechanical equivalence to the obsolete 02371.25M. The substitute parts offer improved compliance status, with all three meeting ROHS3 requirements compared to the non-compliant original.

For applications requiring the broadest regulatory approval coverage, 02331.25MXP and 02331.25MXBP are preferred, as both carry CE, CSA, KC, PSE, and UL certifications. The 02321.25MX125P carries CE, KC, and PSE certifications and features a lower DC cold resistance (0.0685 Ohms) compared to the other substitutes (0.1263 Ohms), which may be relevant for applications sensitive to resistance characteristics.

Frequently Asked Questions (FAQ)

Q: Can the 02331.25MXP, 02321.25MX125P, and 02331.25MXBP be used interchangeably with the 02371.25M?

A: Yes. All substitute parts maintain identical current rating (1.25 A), voltage rating (125 V AC), fuse type (cartridge glass), physical dimensions (5mm x 20mm), response time (medium blow), and breaking capacity (10 kA). They are mechanically and electrically equivalent for direct replacement in fuse holders designed for the original component.

Q: What is the difference between the three substitute parts?

A: The primary differences are series designation (233 for 02331.25MXP and 02331.25MXBP; 232 for 02321.25MX125P), DC cold resistance (0.1263 Ohms for 02331.25MXP and 02331.25MXBP; 0.0685 Ohms for 02321.25MX125P), melting I²t values (3.39 for 02331.25MXP and 02331.25MXBP; 4.11 for 02321.25MX125P), and regulatory certifications. The 02321.25MX125P does not carry CSA or UL certifications.

Q: Why is the original 02371.25M obsolete?

A: The 02371.25M is classified as obsolete by Littelfuse. Active production alternatives with improved compliance characteristics are available as direct substitutes.

Q: Are there packaging differences between the substitute parts?

A: All substitute parts are supplied in bulk packaging. The original 02371.25M packaging type was not specified in available documentation.

Q: Do the substitute parts meet RoHS requirements?

A: Yes. All three substitute parts are ROHS3 compliant, whereas the original 02371.25M is RoHS non-compliant.