Equivalent & Substitute Parts for 3AP 250

Part Overview

The 3AP 250 is a 250 mA, 250 V AC/DC fast-blow glass fuse cartridge manufactured by Bel Fuse Inc. in 3AB/3AG package format with through-hole mounting. This component is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing system maintenance and new design implementations. Substitute parts must maintain electrical performance across current rating, voltage rating, response time, and physical dimensions while meeting applicable regulatory certifications.

Substiute Parts

3AP 250

Bel Fuse Inc.In Stock: 8203AP 250 Datasheet

Current PartRFQ

0318.250HXP

Littelfuse Inc.In Stock: 10640318.250HXP Datasheet

SimilarRFQ

0318.250MXP

Littelfuse Inc.In Stock: 9000318.250MXP Datasheet

SimilarRFQ

0318.250VXP

LittelfuseIn Stock: 10950318.250VXP Datasheet

SimilarRFQ

BK/AGC-V-1/4

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

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility is determined by strict equivalence across the following parameters:

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

All substitute parts listed meet these criteria. Secondary parameters including breaking capacity, melting I²t, DC cold resistance, and regulatory certifications are provided for engineering evaluation but do not disqualify substitution based on the primary electrical and mechanical specifications.

Parameter Comparison

Engineering Selection Recommendations

All four substitute parts satisfy the core electrical and mechanical requirements for direct substitution with the 3AP 250. Selection among active alternatives should consider the following factors:

Littelfuse 0318.250HXP, 0318.250MXP, and 0318.250VXP are functionally equivalent with ROHS3 compliance and active product status. These parts carry CE, CSA, and UL certifications. Melting I²t values of 0.0355 and DC cold resistance of 2.01 Ohms differ from the original specification but remain within the substitution parameters.

Eaton BK/AGC-V-1/4 is functionally equivalent with active product status and CSA/UL certifications. This part exhibits the lowest DC cold resistance at 1.55 Ohms and melting I²t of 0.016, differing from the original specification. CE certification is not listed for this variant.

For applications requiring RoHS3 compliance, Littelfuse alternatives are preferred. For applications with existing Eaton component ecosystems, the BK/AGC-V-1/4 provides functional equivalence. The original 3AP 250 remains available in inventory (720 Pcs) for legacy system support where exact specification matching is required.

Frequently Asked Questions (FAQ)

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

A: Yes. All three Littelfuse parts meet the core substitution criteria: 250 mA current rating, 250 V AC voltage rating, fast-blow response, 3AB/3AG package, and through-hole mounting. Physical dimensions are within tolerance (0.275" Dia x 1.288" L vs. 0.272" Dia x 1.280" L). The parts differ in melting I²t and DC cold resistance but remain functionally equivalent for the specified electrical parameters.

Q: What is the difference between the Littelfuse variants 0318.250HXP, 0318.250MXP, and 0318.250VXP?

A: All three Littelfuse variants share identical electrical specifications, physical dimensions, and certifications. The designations reflect internal product line differentiation. From an engineering substitution perspective, they are equivalent.

Q: Is the Eaton BK/AGC-V-1/4 a suitable replacement for the 3AP 250?

A: Yes. The Eaton part meets all core substitution criteria with 250 mA current rating, 250 V AC voltage rating, fast-blow response, 3AB/3AG package, and through-hole mounting. Physical dimensions are within tolerance. The part carries CSA and UL certifications but does not list CE certification.

Q: Why do the substitute parts have different breaking capacity values than the 3AP 250?

A: Breaking capacity is a secondary parameter not used to determine substitution eligibility. The 3AP 250 specifies 200A breaking capacity while Littelfuse and Eaton alternatives specify 35A. Both values are valid for the 250 mA, 250 V rating. System design must account for the actual breaking capacity of the selected part.

Q: Are the Littelfuse alternatives RoHS compliant?

A: Yes. The Littelfuse 0318.250HXP, 0318.250MXP, and 0318.250VXP are ROHS3 compliant. The original 3AP 250 and Eaton BK/AGC-V-1/4 are RoHS non-compliant. For applications requiring RoHS compliance, Littelfuse alternatives are required.

Q: What certifications apply to each substitute part?

A: Littelfuse 0318.250HXP, 0318.250MXP, and 0318.250VXP carry CE, CSA, and UL certifications. Eaton BK/AGC-V-1/4 carries CSA and UL certifications. The original 3AP 250 carries CE, CSA, PSE, and UL certifications. System requirements determine which certifications are necessary.