Equivalent & Substitute Parts for BK/AGC-B-1/2

Part Overview

The BK/AGC-B-1/2 is a 500 mA, 250 V AC/DC fast-blow glass cartridge fuse manufactured by Eaton - Electronics Division. This fuse is designed for 3AB and 3AG holder applications with dimensions of 0.250" diameter by 1.250" length (6.35 mm × 31.75 mm). The part maintains active product status and is approved by CSA and UL agencies. Alternative equivalent and substitute parts are available from both Eaton and Littelfuse Inc. to support procurement flexibility and supply chain continuity.

Substiute Parts

BK/AGC-B-1/2

Eaton - Electronics DivisionIn Stock: 812BK/AGC-B-1/2 Datasheet

Current PartRFQ

BK/AGC-1/2-R

Eaton - Electronics DivisionIn Stock: 766BK/AGC-1/2-R Datasheet

Parametric EquivalentRFQ

0312.500MXP

Littelfuse Inc.In Stock: 21180312.500MXP Datasheet

SimilarRFQ

0312.500VXP

Littelfuse Inc.In Stock: 10580312.500VXP Datasheet

SimilarRFQ

0312.500HXP

Littelfuse Inc.In Stock: 40160312.500HXP Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the BK/AGC-B-1/2 is determined by strict equivalence across the following critical parameters:

Mandatory Matching Parameters:

• Current Rating: 500 mA
• Voltage Rating (AC): 250 V
• Fuse Type: Cartridge, Glass
• Response Time: Fast Blow
• Package / Case: 3AB, 3AG, 1/4" × 1-1/4"
• Size / Dimension: 0.250" Dia × 1.250" L (6.35 mm × 31.75 mm)
• Breaking Capacity @ Rated Voltage: 35 A
• Operating Temperature Range: -55°C ~ 125°C

All substitute parts listed maintain identical values across these parameters, ensuring direct functional and mechanical compatibility within 3AB and 3AG holder assemblies. Variations in secondary parameters such as melting I²t, DC cold resistance, and RoHS compliance status do not affect substitutability but are documented for engineering reference.

Parameter Comparison

Engineering Selection Recommendations

Eaton BK/AGC-1/2-R: This part is a parametric equivalent to the BK/AGC-B-1/2 with identical electrical and mechanical specifications. The primary distinction is RoHS3 compliance status. Selection of BK/AGC-1/2-R is appropriate for applications requiring RoHS compliance or when supply from Eaton's revised product line is preferred.

Littelfuse 0312.500HXP, 0312.500VXP, 0312.500MXP: These three Littelfuse parts are parametric equivalents meeting all critical electrical and mechanical requirements. All three carry CE, CSA, and UL approvals, providing broader international certification coverage compared to the original BK/AGC-B-1/2. All three are RoHS3 compliant. Selection among these three Littelfuse variants is based on procurement availability and supply chain logistics, as they are functionally interchangeable.

Compliance Considerations: The original BK/AGC-B-1/2 is RoHS non-compliant. Applications subject to RoHS regulations should transition to BK/AGC-1/2-R or any of the Littelfuse equivalents (0312.500HXP, 0312.500VXP, 0312.500MXP), all of which are ROHS3 compliant.

Frequently Asked Questions (FAQ)

Q: Can BK/AGC-1/2-R be used as a direct replacement for BK/AGC-B-1/2?

A: Yes. BK/AGC-1/2-R is a parametric equivalent with identical current rating (500 mA), voltage rating (250 V AC), fuse type (cartridge glass), response time (fast blow), package designation (3AB, 3AG), physical dimensions (0.250" × 1.250"), breaking capacity (35 A), and operating temperature range (-55°C ~ 125°C). The primary difference is RoHS3 compliance status.

Q: Are the Littelfuse 0312.500HXP, 0312.500VXP, and 0312.500MXP parts interchangeable?

A: Yes. All three Littelfuse parts are parametric equivalents with identical electrical and mechanical specifications. They share the same current rating, voltage rating, fuse type, response time, package designation, physical dimensions, breaking capacity, and operating temperature range. Selection among them is based on availability and supply chain considerations.

Q: What is the significance of the melting I²t difference between Eaton and Littelfuse parts?

A: The melting I²t value (0.385 for Eaton parts versus 0.483 for Littelfuse parts) represents the thermal energy required to melt the fuse element. Both values fall within acceptable parameters for 500 mA fast-blow fuses and do not affect substitutability. This parameter is provided for engineering reference and detailed thermal analysis if required.

Q: Do all substitute parts fit in 3AB and 3AG holders?

A: Yes. All substitute parts maintain the identical package designation (3AB, 3AG) and physical dimensions (0.250" diameter × 1.250" length / 6.35 mm × 31.75 mm). They are mechanically compatible with any holder designed for these specifications.

Q: Which substitute part should be selected for applications requiring international compliance?

A: The Littelfuse parts (0312.500HXP, 0312.500VXP, 0312.500MXP) carry CE, CSA, and UL approvals, providing broader international certification coverage. The Eaton BK/AGC-1/2-R carries CSA and UL approvals. Selection depends on specific regional regulatory requirements.

Q: Is there a difference in DC cold resistance between the main part and substitutes?

A: The BK/AGC-B-1/2 and BK/AGC-1/2-R have a DC cold resistance of 0.483 Ohms, while the Littelfuse parts have 0.498 Ohms. This minor difference does not affect substitutability and is provided for detailed circuit analysis if required.