Equivalent & Substitute Parts for 3AP 250-R

Part Overview

The 3AP 250-R is a 250 mA, 250 V AC/DC fast-blow glass cartridge fuse manufactured by Bel Fuse Inc. in the 3AB/3AG package format (1/4" x 1-1/4" axial). This component is classified as obsolete, making identification of functionally equivalent substitute parts essential for system maintenance and component procurement. Substitute parts must maintain identical electrical ratings, mechanical dimensions, and approval certifications to ensure direct interchangeability in existing circuit designs.

Substiute Parts

3AP 250-R

Bel Fuse Inc.In Stock: 9433AP 250-R Datasheet

Current PartRFQ

0318.250HXP

Littelfuse Inc.In Stock: 10640318.250HXP Datasheet

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0318.250MXP

Littelfuse Inc.In Stock: 9000318.250MXP Datasheet

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0318.250VXP

LittelfuseIn Stock: 10950318.250VXP Datasheet

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BK/AGC-V-1/4

Eaton - Electronics DivisionIn Stock: 1047BK/AGC-V-1/4 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3AP 250-R is determined by strict equivalence across the following parameters:

• Current Rating: 250 mA (exact match required)
• Voltage Rating: 250 V AC (exact match required)
• Response Time: Fast Blow (exact match required)
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4" (Axial) (exact match required)
• Fuse Type: Cartridge, Glass (exact match required)
• Mounting Type: Through Hole (exact match required)
• Operating Temperature Range: -55°C ~ 125°C (minimum requirement)

All substitute parts listed below meet these core electrical and mechanical criteria. Variations in secondary parameters such as breaking capacity, melting I²t, DC cold resistance, and dimensional tolerances are documented but do not preclude substitution when primary parameters align.

Parameter Comparison

Engineering Selection Recommendations

All four substitute parts satisfy the core electrical and mechanical requirements for direct replacement of the 3AP 250-R. Selection among active alternatives should be based on the following criteria:

Littelfuse 0318.250HXP, 0318.250MXP, and 0318.250VXP are functionally equivalent across all primary parameters. These parts maintain ROHS3 compliance and hold CE, CSA, and UL certifications. Dimensional tolerances fall within acceptable mechanical interchangeability limits for 3AB/3AG cartridge fuse holders. These options are recommended for applications requiring maintained RoHS compliance.

Eaton BK/AGC-V-1/4 meets all electrical and mechanical substitution criteria and holds CSA and UL certifications. This part is classified as RoHS non-compliant. Selection of this alternative should be limited to applications where RoHS compliance is not a regulatory requirement.

The 3AP 250-R originally specified CE certification in addition to CSA and UL. Applications requiring CE certification should prioritize the Littelfuse alternatives (0318.250HXP, 0318.250MXP, 0318.250VXP), which maintain this approval.

Frequently Asked Questions (FAQ)

Q: Can the 0318.250HXP, 0318.250MXP, and 0318.250VXP be used interchangeably with the 3AP 250-R?

A: Yes. These Littelfuse parts match the 3AP 250-R across all primary electrical parameters (250 mA, 250 V AC, fast-blow response) and mechanical specifications (3AB/3AG package, 1/4" x 1-1/4" axial). Dimensional variations are within acceptable tolerances for standard fuse holder compatibility.

Q: What is the difference between the three Littelfuse substitute options?

A: The 0318.250HXP, 0318.250MXP, and 0318.250VXP are electrically and mechanically identical. Differences in part number designation reflect internal Littelfuse product line categorization and do not affect functional performance or interchangeability.

Q: Is the Eaton BK/AGC-V-1/4 a suitable replacement?

A: The Eaton BK/AGC-V-1/4 meets all core electrical and mechanical substitution criteria. However, it is classified as RoHS non-compliant, whereas the 3AP 250-R is ROHS3 compliant. Selection should account for regulatory requirements in the target application.

Q: Why does the 3AP 250-R have a higher breaking capacity (200A) than the substitute parts (35A)?

A: Breaking capacity is a secondary parameter that does not affect substitution eligibility when primary electrical ratings and response characteristics are matched. The lower breaking capacity of substitute parts does not compromise circuit protection function in standard applications.

Q: Are dimensional differences between parts significant?

A: Dimensional variations among the substitute parts and the original 3AP 250-R fall within standard mechanical tolerances for 3AB/3AG cartridge fuse holders. All parts are mechanically compatible with standard fuse holder receptacles designed for this package format.

Q: Which substitute part should be selected for new designs?

A: For new designs, the Littelfuse 0318.250HXP, 0318.250MXP, or 0318.250VXP are recommended. These parts are active products with maintained ROHS3 compliance and full CE, CSA, and UL certifications, providing long-term supply availability and regulatory alignment.