BK/MDA-4 Ceramic Fuse Cartridge Equivalent & Substitute Parts

Part Overview

The BK/MDA-4 is a 4 A, 250 V AC ceramic fuse cartridge manufactured by Eaton - Electronics Division. This component is classified as obsolete, requiring identification of active equivalent and substitute parts for ongoing system maintenance and new designs. The MDA series ceramic cartridge fuse operates as a slow-blow protection device in 3AB and 3AG holder configurations with 1/4" x 1-1/4" dimensions. Substitution is necessary to ensure continued availability and compliance with current regulatory standards, as the original part has reached end-of-life status.

Substiute Parts

BK/MDA-4

Eaton - Electronics DivisionIn Stock: 967BK/MDA-4 Datasheet

Current PartRFQ

BK/MDA-4-R

Eaton - Electronics DivisionIn Stock: 1593BK/MDA-4-R Datasheet

DirectRFQ

MDA-4-R

Eaton - Electronics DivisionIn Stock: 806MDA-4-R Datasheet

DirectRFQ

0001.2530

SCHURTER Inc.In Stock: 9330001.2530 Datasheet

DirectRFQ

0326004.HXP

Littelfuse Inc.In Stock: 27000326004.HXP Datasheet

DirectRFQ

0326004.MXP

Littelfuse Inc.In Stock: 21210326004.MXP Datasheet

DirectRFQ

0326004.VXP

Littelfuse Inc.In Stock: 11160326004.VXP Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the BK/MDA-4 is determined by strict equivalence across the following electrical and mechanical parameters:

Primary Substitution Criteria:

• Current Rating: 4 A (exact match required)
• Voltage Rating (AC): 250 V (exact match required)
• Fuse Type: Cartridge, Ceramic (exact match required)
• Response Time: Slow Blow (exact match required)
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4" (exact match required)
• Mounting Type: Requires Holder (exact match required)

Secondary Compatibility Factors:

• Breaking Capacity @ Rated Voltage: 200 A minimum
• Physical Dimensions: 0.250" Dia x 1.250" L (6.35mm x 31.75mm)

All substitute parts listed meet these criteria. The BK/MDA-4-R (Eaton), MDA-4-R (Eaton), and Littelfuse 326 series parts (0326004.HXP, 0326004.MXP, 0326004.VXP) are direct ceramic cartridge equivalents. The SCHURTER 0001.2530 is a glass cartridge fuse with identical electrical ratings and package dimensions but differs in fuse element material and breaking capacity characteristics.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: Eaton BK/MDA-4-R or MDA-4-R

The BK/MDA-4-R and MDA-4-R are direct manufacturer equivalents from Eaton - Electronics Division. Both parts maintain identical electrical specifications (4 A, 250 V AC, slow-blow ceramic cartridge) and mechanical compatibility (3AB, 3AG package, 1/4" x 1-1/4" dimensions). Both are active products with ROHS3 compliance and CSA/UL certifications. The BK/MDA-4-R carries CE certification in addition to CSA and UL. These parts provide the most direct substitution path with no design modifications required.

Secondary Recommendation: Littelfuse 326 Series (0326004.HXP, 0326004.MXP, 0326004.VXP)

The Littelfuse 326 series ceramic cartridge fuses meet all electrical and mechanical requirements. These parts feature higher breaking capacity (400 A versus 200 A), ROHS3 compliance, and broader temperature operating range (-55°C to 125°C). All three variants carry CE, CSA, PSE, and UL certifications. The variants differ in packaging designation only; electrical performance is identical. These parts are suitable for direct substitution with enhanced performance margins.

Alternative Option: SCHURTER 0001.2530

The SCHURTER 0001.2530 is a glass cartridge fuse with identical current and voltage ratings and package dimensions. This part differs in fuse element material (glass versus ceramic) and breaking capacity (1.5 kA AC versus 200 A). The glass construction and higher breaking capacity may be appropriate for applications requiring different thermal response characteristics. This part carries cURus certification and ROHS3 compliance with operating temperature range of -40°C to 85°C.

Frequently Asked Questions (FAQ)

Q: Can BK/MDA-4-R directly replace BK/MDA-4 without any circuit modifications?

A: Yes. The BK/MDA-4-R is a direct equivalent with identical electrical ratings (4 A, 250 V AC), fuse type (ceramic cartridge), response time (slow-blow), and package configuration (3AB, 3AG, 1/4" x 1-1/4"). No circuit modifications are required. The primary difference is product status (active versus obsolete) and RoHS compliance.

Q: What is the difference between the Eaton MDA-4-R and BK/MDA-4-R?

A: Both are Eaton ceramic cartridge fuses with identical electrical and mechanical specifications. The designation difference reflects internal Eaton part numbering conventions. Both are active products with ROHS3 compliance. The BK/MDA-4-R includes CE certification; MDA-4-R carries CSA and UL certifications.

Q: Why do the Littelfuse 326 series parts have higher breaking capacity (400 A) than the original BK/MDA-4 (200 A)?

A: Breaking capacity is determined by fuse element design and ceramic body construction. The Littelfuse 326 series uses enhanced ceramic formulation and element geometry that provides superior arc suppression and current interruption capability. This higher breaking capacity does not affect the fuse's response to normal circuit operation; it only improves performance during fault conditions. The 4 A current rating and slow-blow response time remain identical.

Q: Can the SCHURTER 0001.2530 glass fuse replace the ceramic BK/MDA-4?

A: The SCHURTER 0001.2530 meets all electrical and mechanical requirements (4 A, 250 V AC, slow-blow, 3AB/3AG package, 1/4" x 1-1/4" dimensions). However, it uses glass construction instead of ceramic. Glass and ceramic fuses exhibit different thermal response characteristics and breaking capacity (1.5 kA AC for glass versus 200 A for ceramic). Substitution is electrically valid but introduces different fault-current handling behavior. Verify application requirements before selection.

Q: Are all substitute parts RoHS compliant?

A: The original BK/MDA-4 is RoHS non-compliant. All substitute parts listed (BK/MDA-4-R, MDA-4-R, Littelfuse 326 series, and SCHURTER 0001.2530) are ROHS3 compliant, meeting current environmental regulations.

Q: What certifications apply to each substitute part?

A: BK/MDA-4-R carries CE, CSA, and UL certifications. MDA-4-R carries CE, CSA, and UL certifications. Littelfuse 326 series (all variants) carry CE, CSA, PSE, and UL certifications. SCHURTER 0001.2530 carries cURus certification. Verify that selected part certifications meet your application and regional requirements.

Q: Can I use Littelfuse 0326004.HXP, 0326004.MXP, or 0326004.VXP interchangeably?

A: Yes. All three Littelfuse variants are electrically and mechanically identical. They differ only in packaging designation (HXP, MXP, VXP represent different distribution channel or tape/reel configurations). Electrical performance, current rating, voltage rating, response time, and physical dimensions are identical across all three variants.