BK1/MDA-7-R Ceramic Fuse Equivalent & Substitute Parts

Part Overview

The BK1/MDA-7-R is a 7 A, 250 V AC/DC ceramic cartridge fuse manufactured by Eaton - Electronics Division. This component is classified as obsolete, requiring identification of active equivalent alternatives for continued system support and procurement. The fuse operates as a slow-blow cartridge type, designed for 3AB and 3AG holder compatibility with dimensions of 0.250" diameter by 1.250" length (6.35mm x 31.75mm). Substitution is necessary due to the obsolete product status while maintaining identical electrical and mechanical specifications.

Substiute Parts

BK1/MDA-7-R

Eaton - Electronics DivisionIn Stock: 1121BK1/MDA-7-R Datasheet

Current PartRFQ

MDA-7-R

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

SimilarRFQ

BK/MDA-7-R

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

Parametric EquivalentRFQ

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

GSA 7-R

Bel Fuse Inc.In Stock: 1032GSA 7-R Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the BK1/MDA-7-R is determined by strict equivalence across the following parameters:

Primary Equivalence Criteria:

• Current Rating: 7 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)
• Size / Dimension: 0.250" Dia x 1.250" L (exact match required)

Secondary Compatibility Factors:

• Mounting Type: Requires Holder (all substitutes match)
• RoHS Status: ROHS3 Compliant (all substitutes match)
• Approval Agencies: CE, CSA, UL minimum certification required

All substitute parts listed below meet these criteria. Variations in breaking capacity, melting I²t, DC cold resistance, and operating temperature ranges do not disqualify substitution when primary parameters are identical.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Eaton Manufacturer):

MDA-7-R and BK/MDA-7-R are direct Eaton equivalents to the obsolete BK1/MDA-7-R. Both are active products with identical electrical specifications, breaking capacity (200 A), and holder compatibility. Selection between these two Eaton variants depends on packaging requirements (MDA-7-R available in bulk; BK/MDA-7-R available in bulk with higher inventory).

Secondary Substitutes (Littelfuse Manufacturer):

0326007.HXP, 0326007.MXP, and 0326007.VXP are Littelfuse Series 326 ceramic cartridge fuses meeting all primary equivalence criteria. These parts feature higher breaking capacity (400 A) and extended operating temperature range (-55°C to 125°C). All three variants carry CE, CSA, UL, and PSE certifications. Selection among these three Littelfuse options depends on specific approval agency requirements for the end application.

Tertiary Substitute (Bel Fuse Manufacturer):

GSA 7-R is a Bel Fuse Series GSA ceramic cartridge fuse meeting all primary equivalence criteria. This part maintains 200 A breaking capacity matching the original BK1/MDA-7-R and carries CE, CSA, cURus, and PSE certifications. Dimensional tolerance is 0.250" x 1.252" (6.35mm x 31.80mm), representing a 0.002" length variation within standard mechanical tolerance.

Compliance Considerations:

All substitute parts are ROHS3 compliant and REACH unaffected. Selection should prioritize parts carrying certifications required by the end-use application. Littelfuse variants (0326007 series) provide broader certification coverage including K-MARK and PSE in addition to CE, CSA, and UL.

Frequently Asked Questions (FAQ)

Q: Can I substitute BK1/MDA-7-R with MDA-7-R or BK/MDA-7-R?

A: Yes. MDA-7-R and BK/MDA-7-R are active Eaton products with identical electrical and mechanical specifications to the obsolete BK1/MDA-7-R. Both are direct substitutes requiring no circuit or holder modifications.

Q: What is the difference between Eaton MDA series and Littelfuse 0326007 series substitutes?

A: Both meet all primary equivalence criteria (7 A, 250 V, slow-blow, 3AB/3AG package). Littelfuse variants feature higher breaking capacity (400 A vs. 200 A) and wider operating temperature range (-55°C to 125°C). Eaton variants maintain the original 200 A breaking capacity. Selection depends on application requirements and required certifications.

Q: Are there dimensional differences between substitute parts?

A: All substitutes maintain the 0.250" diameter specification. Length specifications are 1.250" (31.75mm) for Eaton and Littelfuse parts, and 1.252" (31.80mm) for Bel Fuse GSA 7-R. This 0.002" variation is within standard mechanical tolerance and does not affect holder compatibility.

Q: Do all substitute parts fit in 3AB and 3AG holders?

A: Yes. All substitute parts are specified for 3AB and 3AG holder compatibility. Mechanical dimensions and cartridge design ensure proper fit and electrical contact in these standard holders.

Q: Which substitute offers the broadest certification coverage?

A: Littelfuse 0326007 series parts (HXP, MXP, VXP) carry the most comprehensive certification set: CE, CSA, K-MARK, PSE, and UL. Selection among these three variants depends on specific application certifications required.

Q: Can I use GSA 7-R as a substitute?

A: Yes. GSA 7-R meets all primary equivalence criteria and carries CE, CSA, cURus, and PSE certifications. The 0.002" length variation (1.252" vs. 1.250") is within standard tolerance and does not affect functionality or holder compatibility.

Q: What is the difference between slow-blow and fast-blow fuses?

A: The BK1/MDA-7-R and all listed substitutes are slow-blow (time-delay) fuses. This response time characteristic is identical across all substitutes and must not be changed during replacement.

Q: Are all substitutes ROHS3 compliant?

A: Yes. All substitute parts listed are ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements.