BK/MDA-7 Ceramic Fuse Equivalent & Substitute Parts

Part Overview

The BK/MDA-7 is a 7 A, 250 V AC/DC ceramic cartridge fuse manufactured by Eaton - Electronics Division. This component is classified as obsolete product status. The fuse requires a 3AB or 3AG holder and features slow-blow response characteristics with a breaking capacity of 200 A at rated voltage. Due to its obsolete status, equivalent substitute parts from active product lines are necessary to maintain circuit protection functionality in applications requiring 7 A, 250 V ceramic cartridge fuses with 3AB/3AG package compatibility.

Substiute Parts

BK/MDA-7

Eaton - Electronics DivisionIn Stock: 1059BK/MDA-7 Datasheet

Current PartRFQ

BK/MDA-7-R

Eaton - Electronics DivisionIn Stock: 2088BK/MDA-7-R Datasheet

DirectRFQ

MDA-7-R

Eaton - Electronics DivisionIn Stock: 1103MDA-7-R Datasheet

SimilarRFQ

0326007.HXP

LittelfuseIn Stock: 8650326007.HXP Datasheet

DirectRFQ

0326007.MXP

Littelfuse Inc.In Stock: 11250326007.MXP Datasheet

DirectRFQ

0326007.VXP

Littelfuse Inc.In Stock: 8400326007.VXP Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the BK/MDA-7 is determined by strict equivalence across the following critical parameters:

Mandatory Matching Parameters:

• Current Rating: 7 A
• Voltage Rating (AC): 250 V
• Fuse Type: Cartridge, Ceramic
• Response Time: Slow 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)
• Mounting Type: Requires Holder

All substitute parts listed meet these mandatory parameters. Variations in breaking capacity, melting I²t, DC cold resistance, and approval agencies do not disqualify substitution when the above parameters are identical. Substitute parts are grouped into two categories: direct Eaton equivalents (BK/MDA-7-R, MDA-7-R) and cross-manufacturer alternatives (Littelfuse 0326007 series).

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Eaton MDA Series):

BK/MDA-7-R and MDA-7-R are direct Eaton equivalents with active product status. Both parts maintain identical electrical specifications to the obsolete BK/MDA-7 across all critical parameters. BK/MDA-7-R carries CE, CSA, and UL approvals, while MDA-7-R carries the same certification set. Both are ROHS3 compliant, addressing environmental compliance requirements that the original BK/MDA-7 does not meet. Selection between these two Eaton alternatives depends on packaging requirements (both available in bulk) and inventory availability.

Secondary Substitutes (Littelfuse 326 Series):

The Littelfuse 0326007.HXP, 0326007.MXP, and 0326007.VXP parts are functionally equivalent across all mandatory parameters. These parts feature higher breaking capacity (400 A versus 200 A), expanded approval agency coverage (including K-MARK, PSE, and KC certifications), and specified operating temperature range (-55°C ~ 125°C). The Littelfuse alternatives are ROHS3 compliant and REACH unaffected. Selection of Littelfuse parts is appropriate when higher breaking capacity or extended temperature range operation is required, or when Littelfuse supply chain availability is preferred.

Compliance Consideration:

The original BK/MDA-7 is RoHS non-compliant. All substitute parts (Eaton and Littelfuse) are ROHS3 compliant, making them suitable for applications subject to RoHS directives.

Frequently Asked Questions (FAQ)

Q: Can BK/MDA-7-R directly replace BK/MDA-7 in existing applications?

A: Yes. BK/MDA-7-R matches all critical electrical and mechanical parameters: 7 A current rating, 250 V AC voltage rating, slow-blow response, ceramic cartridge type, and 3AB/3AG package compatibility. Physical dimensions are identical (0.250" Dia x 1.250" L). The part requires the same holder type and mounts identically.

Q: What is the difference between BK/MDA-7-R and MDA-7-R?

A: Both parts are Eaton MDA series equivalents with identical electrical specifications and approvals (CE, CSA, UL). The primary difference is the part number prefix: BK/MDA-7-R includes the "BK/" designation while MDA-7-R does not. Both are active products in bulk packaging with equivalent functionality.

Q: Why do Littelfuse 0326007 parts have higher breaking capacity (400 A vs. 200 A)?

A: Breaking capacity is a design characteristic of the fuse element and holder combination. The Littelfuse 326 series is engineered with higher breaking capacity while maintaining identical current rating, voltage rating, response time, and package specifications. Higher breaking capacity does not affect normal circuit operation but provides enhanced protection margin in fault conditions.

Q: Are Littelfuse 0326007.HXP, 0326007.MXP, and 0326007.VXP interchangeable?

A: Yes. All three Littelfuse parts are functionally equivalent. They share identical electrical ratings (7 A, 250 V AC), response characteristics (slow-blow), package type (3AB/3AG), and physical dimensions (0.250" Dia x 1.250" L). Differences in approval agency certifications (K-MARK, PSE, KC) reflect regional regulatory requirements rather than functional differences. Selection depends on geographic market requirements and supply availability.

Q: Can I use a substitute part with higher breaking capacity in a circuit designed for 200 A breaking capacity?

A: Yes. Higher breaking capacity (400 A in Littelfuse parts) is a protective enhancement. The fuse will operate identically under normal circuit conditions and provide equal or superior protection in fault scenarios. No circuit redesign is required.

Q: What is the significance of the operating temperature range specified for Littelfuse parts?

A: Littelfuse 0326007 parts specify -55°C ~ 125°C operating temperature range, while Eaton parts do not specify this parameter. This specification indicates the temperature limits within which the fuse maintains rated performance. For applications operating within standard industrial temperature ranges, this difference is not functionally significant. For extreme temperature applications, Littelfuse parts provide documented temperature performance.

Q: Are all substitute parts RoHS compliant?

A: Yes. All substitute parts (BK/MDA-7-R, MDA-7-R, and all Littelfuse 0326007 variants) are ROHS3 compliant. The original BK/MDA-7 is RoHS non-compliant. Substitution with any listed alternative part addresses RoHS compliance requirements.

Q: Which substitute should I select for new designs?

A: For new designs, select from active product status parts: BK/MDA-7-R, MDA-7-R (Eaton), or 0326007.HXP, 0326007.MXP, 0326007.VXP (Littelfuse). All are active products with full certification support. Eaton parts maintain the original manufacturer lineage. Littelfuse parts offer higher breaking capacity and extended temperature specification. Selection depends on supply chain preference, regional certifications required, and specific application temperature requirements.