Equivalent & Substitute Parts for BK/AGC-3/8

Part Overview

The BK/AGC-3/8 is a 375 mA, 250 V AC/DC fast-blow glass cartridge fuse manufactured by Eaton - Electronics Division. This component is classified as obsolete and requires a compatible fuse holder (3AB, 3AG type) for installation. Due to its obsolete status, equivalent substitute parts from both Eaton and Littelfuse are available to maintain circuit protection functionality in applications requiring 375 mA rated protection at 250 V.

Substiute Parts

BK/AGC-3/8

Eaton - Electronics DivisionIn Stock: 868BK/AGC-3/8 Datasheet

Current PartRFQ

AGC-3/8-R

Eaton - Electronics DivisionIn Stock: 885AGC-3/8-R Datasheet

DirectRFQ

BK/AGC-3/8-R

Eaton - Electronics DivisionIn Stock: 1184BK/AGC-3/8-R Datasheet

DirectRFQ

0312.375HXP

Littelfuse Inc.In Stock: 11320312.375HXP Datasheet

SimilarRFQ

0312.375MXP

Littelfuse Inc.In Stock: 22530312.375MXP Datasheet

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0312.375VXP

Littelfuse Inc.In Stock: 10700312.375VXP Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the BK/AGC-3/8 is determined by strict equivalence across the following electrical and mechanical parameters:

Critical Matching Parameters:

• Current Rating: 375 mA (exact match required)
• Voltage Rating (AC): 250 V (exact match required)
• Fuse Type: Cartridge, Glass (exact match required)
• Response Time: Fast Blow (exact match required)
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4" (exact match required)
• Physical Dimensions: 0.250" Dia x 1.250" L (exact match required)
• Breaking Capacity @ Rated Voltage: 35A (exact match required)

All substitute parts listed below meet these critical parameters and are therefore electrically and mechanically interchangeable with the BK/AGC-3/8 in applications requiring 375 mA protection at 250 V AC/DC.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: AGC-3/8-R or BK/AGC-3/8-R

Both AGC-3/8-R and BK/AGC-3/8-R are manufactured by Eaton - Electronics Division and maintain identical electrical characteristics to the obsolete BK/AGC-3/8. Both parts are active products with RoHS compliance (AGC-3/8-R is RoHS Compliant; BK/AGC-3/8-R is ROHS3 Compliant). These parts carry CSA and UL approvals and are the direct successors to the obsolete model.

Secondary Recommendation: Littelfuse 0312 Series (0312.375HXP, 0312.375MXP, 0312.375VXP)

The Littelfuse 0312 series parts are active products with ROHS3 compliance and CE, CSA, and UL approvals. These parts meet all critical electrical and mechanical parameters. Note that Littelfuse parts exhibit higher DC cold resistance (0.825 Ohms versus 0.703 Ohms) and higher melting I²t values (0.185 versus 0.09), which remain within acceptable substitution parameters for this fuse category.

Compliance Considerations:

All substitute parts listed are compliant with current regulatory standards. The BK/AGC-3/8 is RoHS non-compliant and obsolete; selection of an active, compliant substitute is recommended for new designs and ongoing maintenance applications.

Frequently Asked Questions (FAQ)

Q: Can AGC-3/8-R directly replace BK/AGC-3/8?

A: Yes. AGC-3/8-R is electrically and mechanically equivalent to BK/AGC-3/8. Both are 375 mA, 250 V fast-blow glass cartridge fuses in 3AB/3AG package format with identical breaking capacity and operating temperature range. AGC-3/8-R is an active product with RoHS compliance.

Q: What is the difference between AGC-3/8-R and BK/AGC-3/8-R?

A: Both parts are manufactured by Eaton - Electronics Division and are electrically identical. The primary difference is RoHS compliance status: AGC-3/8-R is RoHS Compliant, while BK/AGC-3/8-R is ROHS3 Compliant. Both are active products suitable for direct substitution.

Q: Can Littelfuse 0312 series fuses replace Eaton AGC fuses?

A: Yes. The Littelfuse 0312.375HXP, 0312.375MXP, and 0312.375VXP are electrically and mechanically equivalent to the BK/AGC-3/8. All meet the critical parameters: 375 mA current rating, 250 V voltage rating, fast-blow response, 3AB/3AG package, and 35A breaking capacity. Littelfuse parts carry CE, CSA, and UL approvals.

Q: Are there differences in DC cold resistance between substitute parts?

A: Yes. Eaton AGC parts (BK/AGC-3/8, AGC-3/8-R, BK/AGC-3/8-R) have 0.703 Ohms DC cold resistance. Littelfuse 0312 series parts have 0.825 Ohms. Both values are within acceptable parameters for this fuse category and do not affect substitution compatibility.

Q: What is the significance of melting I²t values?

A: Melting I²t indicates the thermal energy required to melt the fuse element. Eaton AGC parts have 0.09 melting I²t, while Littelfuse 0312 series parts have 0.185. Both values are provided in the specifications; selection between manufacturers should consider application-specific thermal requirements and existing circuit design validation.

Q: Do all substitute parts require the same holder?

A: Yes. All substitute parts are 3AB/3AG package format with dimensions 0.250" Dia x 1.250" L (6.35mm x 31.75mm). They are mechanically interchangeable and require the same fuse holder as the original BK/AGC-3/8.

Q: Which substitute part has the highest inventory availability?

A: BK/AGC-3/8-R has 1084 pieces in stock, followed by 0312.375MXP with 2178 pieces. Both are active products with immediate availability.

Q: Are all substitute parts RoHS compliant?

A: The original BK/AGC-3/8 is RoHS non-compliant. All substitute parts listed (AGC-3/8-R, BK/AGC-3/8-R, and Littelfuse 0312 series) are RoHS or ROHS3 compliant, meeting current environmental regulations.