Littelfuse 0324.250MXP Equivalent & Substitute Parts

Part Overview

The Littelfuse 0324.250MXP is a 250 mA, 250 V AC / 125 V DC ceramic cartridge fuse with fast-blow response characteristics, designed for through-hole mounting in 3AB/3AG form factor (1/4" x 1-1/4" axial). This component is classified as obsolete, necessitating identification of active equivalent parts to maintain circuit protection functionality in legacy and new designs requiring identical electrical and mechanical specifications.

Substiute Parts

0324.250MXP

Littelfuse Inc.In Stock: 9510324.250MXP Datasheet

Current PartRFQ

0318.250HXP

Littelfuse Inc.In Stock: 10640318.250HXP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 0324.250MXP is determined by the following critical parameters:

• Current Rating: 250 mA (exact match required)
• Voltage Rating - AC: 250 V (exact match required)
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4" (Axial) (exact match required for mechanical compatibility)
• Mounting Type: Through Hole (exact match required)
• Response Time: Fast Blow (exact match required for circuit protection characteristics)

The primary distinction between the main part and its substitute is the fuse element material: the 0324.250MXP uses ceramic construction, while the substitute uses glass construction. Both materials meet the specified electrical and mechanical parameters within the allowed tolerances for this product category.

Parameter Comparison

Engineering Selection Recommendations

The Littelfuse 0318.250HXP serves as the manufacturer-recommended substitute for the obsolete 0324.250MXP. Both components maintain identical current ratings (250 mA), AC voltage ratings (250 V), package form factors (3AB/3AG, 1/4" x 1-1/4"), and fast-blow response characteristics. Both parts carry equivalent regulatory approvals (CE, CSA, UL) and comply with ROHS3 standards.

The 0318.250HXP is classified as active product status, ensuring continued availability and supply chain reliability. The substitution is supported by matching mechanical dimensions and electrical performance within the specified operating temperature range (-55°C to 125°C).

Frequently Asked Questions (FAQ)

Q: Can the 0318.250HXP directly replace the 0324.250MXP in existing designs?

A: Yes. Both parts share identical current ratings (250 mA), AC voltage ratings (250 V), package dimensions (1/4" x 1-1/4" axial), and fast-blow response characteristics. The physical form factor and mounting interface are identical, enabling direct substitution in through-hole applications.

Q: What is the difference between ceramic and glass fuse construction?

A: The 0324.250MXP uses ceramic cartridge construction, while the 0318.250HXP uses glass cartridge construction. Both materials meet the specified electrical parameters and approval requirements for this current and voltage rating. The melting I²t values differ (0.014 vs. 0.0355), reflecting the thermal characteristics of each material.

Q: Are both parts compliant with current regulatory standards?

A: Yes. Both the 0324.250MXP and 0318.250HXP carry CE, CSA, and UL approvals and comply with ROHS3 standards. The 0318.250HXP, as an active product, maintains current compliance documentation.

Q: Why is the 0324.250MXP classified as obsolete?

A: The 0324.250MXP is obsolete, meaning it is no longer manufactured or supported by Littelfuse Inc. The 0318.250HXP is the active equivalent part recommended for new designs and replacement applications.

Q: Are there any voltage rating differences between the two parts?

A: The 0324.250MXP specifies both AC (250 V) and DC (125 V) voltage ratings. The 0318.250HXP specifies 250 V AC with DC rating not specified in the provided data. Both parts are rated for 250 V AC operation, which covers the primary application requirement.