Littelfuse 0318.250H Glass Cartridge Fuse - Equivalent & Substitute Parts

Part Overview

The Littelfuse 0318.250H is a 250 mA, 250 V AC/DC fast-blow glass cartridge fuse in the 3AB/3AG package format (1/4" x 1-1/4" axial). This component is classified as obsolete, though 960 pieces remain in stock as new original inventory. The part operates within the 318 series fuse line and is designed for through-hole mounting applications requiring fast-response overcurrent protection.

Due to the obsolete product status of the 0318.250H, equivalent substitute parts with active product status are available to ensure design continuity and supply chain reliability for new production runs and long-term availability.

Substiute Parts

0318.250H

Littelfuse Inc.In Stock: 9830318.250H Datasheet

Current PartRFQ

0318.250HXP

Littelfuse Inc.In Stock: 10640318.250HXP Datasheet

DirectRFQ

0318.250MXP

Littelfuse Inc.In Stock: 9000318.250MXP Datasheet

Parametric EquivalentRFQ

0318.250VXP

LittelfuseIn Stock: 10950318.250VXP Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 0318.250H is determined by strict equivalence across the following electrical and mechanical parameters:

• Current Rating: 250 mA (exact match required)
• Voltage Rating (AC): 250 V (exact match required)
• Response Time: Fast Blow (exact match required)
• Fuse Type: Cartridge, Glass (exact match required)
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4" (Axial) (exact match required)
• Mounting Type: Through Hole (exact match required)
• Breaking Capacity @ Rated Voltage: 35 A (exact match required)
• Melting I²t: 0.0355 (exact match required)

All three substitute parts—0318.250HXP, 0318.250MXP, and 0318.250VXP—meet these criteria and are therefore direct parametric equivalents of the 0318.250H.

Parameter Comparison

Engineering Selection Recommendations

All three substitute parts—0318.250HXP, 0318.250MXP, and 0318.250VXP—are direct parametric equivalents of the 0318.250H and are electrically and mechanically interchangeable for through-hole mounting applications requiring 250 mA, 250 V fast-blow glass cartridge fuses in the 3AB/3AG package.

The primary distinction between the main part and substitutes is product status: the 0318.250H is obsolete, while all three substitutes maintain active product status. Additionally, the substitute parts carry expanded regulatory approvals (CE certification in addition to CSA and UL) and are ROHS3 compliant, whereas the main part is RoHS non-compliant. The substitute parts also specify an operating temperature range of -55°C to 125°C.

For new designs and production applications, any of the three substitute parts is suitable for direct replacement of the 0318.250H. Selection among the three substitutes may be based on packaging preference (all are supplied in bulk) and inventory availability.

Frequently Asked Questions (FAQ)

Q: Are the substitute parts 0318.250HXP, 0318.250MXP, and 0318.250VXP electrically identical to the 0318.250H?

A: Yes. All three substitute parts match the 0318.250H across all critical electrical parameters: 250 mA current rating, 250 V AC voltage rating, fast-blow response time, 35 A breaking capacity, and 0.0355 melting I²t. DC cold resistance values are nominally equivalent (2 Ohms vs. 2.01 Ohms).

Q: Can the substitute parts be used as direct drop-in replacements in existing designs?

A: Yes. The substitute parts are mechanically and electrically identical to the 0318.250H. They use the same 3AB/3AG package format, 1/4" x 1-1/4" axial dimensions, and through-hole mounting configuration. No circuit board modifications are required.

Q: Why do the substitute parts have different part number suffixes (HXP, MXP, VXP)?

A: The suffixes indicate different packaging or distribution variants within the Littelfuse 318 series. All three variants are parametrically equivalent and interchangeable for electrical and mechanical purposes.

Q: What is the significance of the RoHS3 compliance on the substitute parts?

A: RoHS3 compliance indicates that the substitute parts meet current European Union Restriction of Hazardous Substances regulations. The main part (0318.250H) is RoHS non-compliant. For applications subject to RoHS requirements, the substitute parts are the appropriate choice.

Q: Are there any temperature rating differences between the main part and substitutes?

A: The main part does not specify an operating temperature range. The substitute parts specify -55°C to 125°C. This expanded specification on the substitutes does not affect interchangeability; it provides additional environmental operating data for design validation.