BK/AGC-4AX Glass Cartridge Fuse 4A 250VAC Equivalent & Substitute Parts

Part Overview

The BK/AGC-4AX is a 4 A, 250 V AC/DC fast-blow glass cartridge fuse manufactured by Eaton - Electronics Division. This component is designed for use in 3AB and 3AG fuse holders with standard 1/4" x 1-1/4" dimensions. The part maintains active product status and is suitable for circuit protection applications requiring fast response characteristics. Equivalent and substitute parts are identified based on matching electrical ratings, mechanical dimensions, and functional performance parameters.

Substiute Parts

BK/AGC-4AX

Eaton - Electronics DivisionIn Stock: 876BK/AGC-4AX Datasheet

Current PartRFQ

BK/AGC-4-R

Eaton - Electronics DivisionIn Stock: 2345BK/AGC-4-R Datasheet

Parametric EquivalentRFQ

0312004.HXP

Littelfuse Inc.In Stock: 38230312004.HXP Datasheet

Parametric EquivalentRFQ

0312004.MXP

Littelfuse Inc.In Stock: 21100312004.MXP Datasheet

Parametric EquivalentRFQ

0312004.VXP

Littelfuse Inc.In Stock: 11210312004.VXP Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the BK/AGC-4AX are identified based on strict parametric equivalence. All substitute parts share the following critical parameters with the main part:

• Current Rating: 4 A
• Voltage Rating (AC): 250 V
• Fuse Type: Cartridge, Glass
• Response Time: Fast Blow
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4"
• Size / Dimension: 0.250" Dia x 1.250" L (6.35mm x 31.75mm)
• Breaking Capacity @ Rated Voltage: 200A
• Operating Temperature Range: -55°C ~ 125°C
• Mounting Type: Requires Holder

Substitutes are grouped into two categories: Eaton-manufactured equivalents and Littelfuse-manufactured equivalents. All parts maintain active product status and meet required approval standards.

Parameter Comparison

Engineering Selection Recommendations

Eaton-Manufactured Substitute (BK/AGC-4-R): This part is a direct parametric equivalent to the BK/AGC-4AX, manufactured by the same supplier. It maintains identical electrical ratings, mechanical dimensions, and thermal characteristics. The BK/AGC-4-R carries ROHS3 compliance certification, providing enhanced environmental compliance. This substitute is recommended for applications requiring continuity with Eaton product lines and where inventory availability is a consideration (2321 units in stock).

Littelfuse-Manufactured Substitutes (0312004.HXP, 0312004.MXP, 0312004.VXP): These three parts are parametric equivalents from Littelfuse Inc., all belonging to the 312 series. All three maintain identical current, voltage, and mechanical specifications. The Littelfuse parts carry expanded approval certifications including CE, CSA, KC, PSE, and UL, providing broader international compliance. These substitutes are suitable for applications requiring multi-regional certification support. The three Littelfuse variants differ only in packaging or internal construction designations (HXP, MXP, VXP suffixes) but share identical electrical and mechanical parameters.

All substitute parts maintain active product status and are suitable for direct replacement in 3AB and 3AG fuse holder applications.

Frequently Asked Questions (FAQ)

Q: Can BK/AGC-4-R be used as a direct replacement for BK/AGC-4AX?

A: Yes. The BK/AGC-4-R is a parametric equivalent with identical current rating (4 A), voltage rating (250 V AC), response time (Fast Blow), mechanical dimensions (0.250" Dia x 1.250" L), and breaking capacity (200A). Both parts are manufactured by Eaton and require the same 3AB or 3AG fuse holder.

Q: What is the difference between the Littelfuse 0312004.HXP, 0312004.MXP, and 0312004.VXP parts?

A: All three Littelfuse parts share identical electrical ratings (4 A, 250 V AC), response characteristics (Fast Blow), mechanical dimensions (0.250" Dia x 1.250" L), and approval certifications (CE, CSA, KC, PSE, UL). The suffix designations (HXP, MXP, VXP) indicate internal construction or packaging variants but do not affect functional equivalence or compatibility with 3AB and 3AG fuse holders.

Q: Are there differences in melting I²t values between the main part and substitutes?

A: Yes. The BK/AGC-4AX and BK/AGC-4-R have a melting I²t of 86.56, while the Littelfuse parts (0312004.HXP, 0312004.MXP, 0312004.VXP) have a melting I²t of 28.5. Despite this difference, all parts maintain the same fast-blow response classification and are rated for identical current and voltage parameters. The melting I²t difference reflects different internal construction but does not prevent functional substitution in applications designed for 4 A, 250 V fast-blow fuses.

Q: Do all substitute parts fit in the same fuse holder?

A: Yes. All substitute parts conform to the 3AB and 3AG package standard with dimensions of 0.250" Dia x 1.250" L (6.35mm x 31.75mm). All parts are mechanically compatible with holders designed for this standard.

Q: Which substitute offers the broadest international compliance?

A: The Littelfuse parts (0312004.HXP, 0312004.MXP, 0312004.VXP) carry approval from CE, CSA, KC, PSE, and UL, providing broader international certification coverage compared to the BK/AGC-4AX and BK/AGC-4-R, which carry CSA and UL approvals only.

Q: Are all substitute parts RoHS compliant?

A: The BK/AGC-4-R and all three Littelfuse substitutes (0312004.HXP, 0312004.MXP, 0312004.VXP) are ROHS3 compliant. The BK/AGC-4AX does not specify RoHS status in the provided parameters.