Equivalent & Substitute Parts for BK/MDA-5 Ceramic Fuse Cartridge

Part Overview

The BK/MDA-5 is a 5 A, 250 V AC ceramic fuse cartridge manufactured by Eaton - Electronics Division. This component is classified as obsolete, requiring identification of active substitute parts for continued system support and procurement. The BK/MDA-5 operates as a slow-blow fuse cartridge in the 3AB/3AG form factor (1/4" x 1-1/4"), designed for applications requiring holder-based installation. Substitute parts must maintain electrical compatibility across current rating, voltage rating, response time, and mechanical form factor to ensure direct functional replacement.

Substiute Parts

BK/MDA-5

Eaton - Electronics DivisionIn Stock: 1227BK/MDA-5 Datasheet

Current PartRFQ

BK/MDA-5-R

Eaton - Electronics DivisionIn Stock: 1860BK/MDA-5-R Datasheet

DirectRFQ

MDA-5-R

Eaton - Electronics DivisionIn Stock: 1085MDA-5-R Datasheet

DirectRFQ

0001.2531

SCHURTER Inc.In Stock: 17160001.2531 Datasheet

DirectRFQ

0326005.HXP

Littelfuse Inc.In Stock: 11970326005.HXP Datasheet

DirectRFQ

0326005.MXCCP

Littelfuse Inc.In Stock: 9770326005.MXCCP Datasheet

DirectRFQ

0326005.MXP

Littelfuse Inc.In Stock: 13560326005.MXP Datasheet

DirectRFQ

0326005.VXP

Littelfuse Inc.In Stock: 11270326005.VXP Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility is determined by strict alignment with the following parameters:

Primary Matching Criteria (Non-negotiable):

• Current Rating: 5 A
• Voltage Rating (AC): 250 V
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4"
• Mounting Type: Requires Holder
• Response Time: Slow Blow

Secondary Compatibility Factors:

• Fuse Type: Ceramic cartridge construction preferred for direct replacement; glass cartridge (0001.2531) acceptable if voltage ratings and breaking capacity are compatible
• Breaking Capacity: Substitute must equal or exceed 200 A at rated voltage
• Approval Agencies: Substitute must carry CSA and/or UL certification for equivalent regulatory standing

Substitute Categories:

Category A - Direct Ceramic Cartridge Substitutes (Eaton MDA Series):

• BK/MDA-5-R
• MDA-5-R

These parts maintain identical electrical and mechanical specifications to the main part while offering active product status and improved RoHS compliance.

Category B - Direct Ceramic Cartridge Substitutes (Littelfuse 326 Series):

• 0326005.HXP
• 0326005.MXCCP
• 0326005.MXP
• 0326005.VXP

These parts meet all primary matching criteria with enhanced breaking capacity (400 A) and extended operating temperature range (-55°C to 125°C).

Category C - Glass Cartridge Substitute (SCHURTER SPT Series):

• 0001.2531

This part meets primary electrical criteria but differs in fuse material (glass vs. ceramic) and includes DC voltage rating (63 V). Substitution is valid where glass cartridge construction is acceptable.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Recommended for Direct Replacement):

BK/MDA-5-R and MDA-5-R are the preferred substitutes for the obsolete BK/MDA-5. Both parts are manufactured by Eaton - Electronics Division and maintain identical electrical and mechanical specifications. These substitutes offer active product status, ROHS3 compliance, and expanded regulatory certifications (CE, CSA, UL). Selection between BK/MDA-5-R and MDA-5-R depends on packaging requirements; both are available in bulk packaging with substantial inventory levels (1760 Pcs and 1074 Pcs respectively).

Secondary Substitutes (Littelfuse 326 Series):

The Littelfuse 326 series fuses (0326005.HXP, 0326005.MXCCP, 0326005.MXP, 0326005.VXP) provide enhanced electrical performance characteristics. These ceramic cartridge fuses meet all primary matching criteria and offer superior breaking capacity (400 A vs. 200 A), lower melting I²t (25 vs. 345.9), and extended operating temperature range (-55°C to 125°C). These substitutes carry CE, CSA, PSE, and UL certifications. Selection among the four Littelfuse variants depends on specific packaging or coating requirements; all four maintain identical electrical specifications and are available in bulk quantities (951 to 1330 Pcs).

Alternative Substitute (Glass Cartridge):

The SCHURTER 0001.2531 is a glass cartridge fuse that meets primary electrical criteria (5 A, 250 V AC, slow-blow response, 3AB/3AG form factor). This substitute differs in fuse material composition and includes DC voltage rating (63 V). The 0001.2531 offers superior breaking capacity (1.5 kA AC, 20 kA DC) and carries cURus certification. This substitute is appropriate only where glass cartridge construction is functionally acceptable within the application circuit.

Frequently Asked Questions (FAQ)

Q: Can I use the Littelfuse 326 series fuses as a direct replacement for the BK/MDA-5?

A: Yes. The Littelfuse 0326005.HXP, 0326005.MXCCP, 0326005.MXP, and 0326005.VXP all meet the primary matching criteria: 5 A current rating, 250 V AC voltage rating, slow-blow response time, and 3AB/3AG form factor (1/4" x 1-1/4"). All four parts are physically and electrically compatible with existing 3AB/3AG holders. The Littelfuse variants offer enhanced breaking capacity (400 A) and extended operating temperature range (-55°C to 125°C) compared to the original part.

Q: What is the difference between the Eaton MDA-5-R variants (BK/MDA-5-R and MDA-5-R)?

A: Both BK/MDA-5-R and MDA-5-R are manufactured by Eaton - Electronics Division and maintain identical electrical and mechanical specifications. The primary difference is part numbering convention. Both parts are active products with ROHS3 compliance and CE, CSA, UL certifications. Selection depends on internal procurement systems or supplier availability; both are functionally equivalent.

Q: Why does the SCHURTER 0001.2531 have a different melting I²t value (127) compared to other substitutes?

A: The SCHURTER 0001.2531 is a glass cartridge fuse, whereas the BK/MDA-5 and other ceramic substitutes are ceramic cartridge fuses. The difference in melting I²t reflects the different thermal and electrical characteristics of glass versus ceramic fuse materials. The 0001.2531 is suitable for substitution only where glass cartridge construction is acceptable within the application.

Q: Are all substitute parts RoHS compliant?

A: Yes. All substitute parts listed (BK/MDA-5-R, MDA-5-R, 0326005.HXP, 0326005.MXCCP, 0326005.MXP, 0326005.VXP, and 0001.2531) are ROHS3 compliant. The original BK/MDA-5 is RoHS non-compliant, making substitution necessary for applications requiring RoHS compliance.

Q: What regulatory certifications should I verify for my application?

A: The BK/MDA-5 carries CSA and UL certifications. The Eaton substitutes (BK/MDA-5-R, MDA-5-R) expand certifications to include CE, CSA, and UL. The Littelfuse 326 series includes CE, CSA, PSE, and UL certifications. The SCHURTER 0001.2531 carries cURus certification. Verify that the selected substitute meets the specific regulatory requirements of your application jurisdiction.

Q: Can I use the Littelfuse 326 series fuses in applications with temperature extremes?

A: The Littelfuse 326 series fuses operate across -55°C to 125°C, providing a wider operating temperature range than the original BK/MDA-5 (operating temperature not specified). The SCHURTER 0001.2531 operates across -40°C to 85°C. Verify that the selected substitute's operating temperature range meets your application requirements.

Q: What is the significance of the different DC cold resistance values among substitutes?

A: DC cold resistance affects voltage drop and heat generation during normal operation. The BK/MDA-5 has 0.02355 Ohms, the Eaton substitutes have 0.023 Ohms, and the Littelfuse 326 series have 0.0522 Ohms. Lower resistance values result in lower voltage drop and reduced heat generation. The Littelfuse variants have higher resistance but remain within acceptable limits for 5 A cartridge fuses. Verify that the selected substitute's resistance characteristics are compatible with your circuit design.

Q: Are all substitute parts available in the same packaging format?

A: All substitute parts are available in bulk packaging. The original BK/MDA-5 is listed with standard packaging designation. Inventory levels vary: Eaton BK/MDA-5-R (1760 Pcs), Eaton MDA-5-R (1074 Pcs), Littelfuse variants (951 to 1330 Pcs), and SCHURTER 0001.2531 (1635 Pcs). Confirm packaging and quantity requirements with your supplier.