Equivalent & Substitute Parts for BK/GMC-750MA

Part Overview

The BK/GMC-750MA is a 750 mA, 250 V AC/DC glass cartridge fuse with a 5mm x 20mm form factor manufactured by Eaton - Electronics Division. This component is classified as obsolete, requiring identification of active equivalent alternatives for continued system support and procurement.

Glass cartridge fuses in this specification are used in low-voltage circuit protection applications where medium-blow response characteristics are required. The obsolete status of the main part necessitates substitution with functionally equivalent active alternatives to maintain design continuity and ensure component availability.

Substiute Parts

BK/GMC-750MA

Eaton - Electronics DivisionIn Stock: 1221BK/GMC-750MA Datasheet

Current PartRFQ

BK/GMC-750-R

Eaton - Electronics DivisionIn Stock: 1277BK/GMC-750-R Datasheet

DirectRFQ

BK1/GMC-750-R

Eaton - Electronics DivisionIn Stock: 1813BK1/GMC-750-R Datasheet

Parametric EquivalentRFQ

GMC-750-R

Eaton - Electronics DivisionIn Stock: 1058GMC-750-R Datasheet

Parametric EquivalentRFQ

MSC-750MA

OptiFuseIn Stock: 4531MSC-750MA Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the BK/GMC-750MA is determined by strict equivalence across the following critical parameters:

Primary Equivalence Criteria:

• Current Rating: 750 mA (exact match required)
• Voltage Rating: 250 V AC (exact match required)
• Package / Case: 5mm x 20mm (exact match required)
• Fuse Type: Cartridge, Glass (exact match required)
• Response Time: Medium Blow (exact match required)
• Mounting Type: Requires Holder (exact match required)

Secondary Compatibility Parameters:

• DC Cold Resistance: 0.213 Ohms (Eaton parts); tolerance variations acceptable within OptiFuse specification
• Melting I²t: 0.85 to 0.8669 (within acceptable thermal characteristic range)
• Approval Agencies: CSA, KC-MARK, UL (Eaton); cULus, UL 248 (OptiFuse)

All substitute parts listed meet these criteria and are functionally interchangeable within the specified electrical and mechanical constraints.

Parameter Comparison

Engineering Selection Recommendations

Eaton GMC Series (BK/GMC-750-R, BK1/GMC-750-R, GMC-750-R):

All three Eaton variants are active products with ROHS3 compliance and identical electrical specifications to the obsolete BK/GMC-750MA. These parts maintain the same 35A breaking capacity and 0.85 melting I²t characteristics. Selection among these three Eaton options depends on packaging availability and inventory requirements, as all three are functionally equivalent.

OptiFuse MSC-750MA:

The MSC-750MA is an active product offering higher breaking capacity (100A versus 35A) while maintaining all other critical electrical parameters within acceptable tolerance. This part carries cULus and UL 248 certifications and includes an extended operating temperature range (-55°C to 125°C). The MSC-750MA is suitable for applications requiring enhanced fault current handling capability.

Compliance Considerations:

All substitute parts are ROHS3 compliant, addressing environmental regulatory requirements that the obsolete BK/GMC-750MA does not meet. All alternatives carry recognized safety certifications (UL, CSA, or cULus) appropriate for circuit protection applications.

Frequently Asked Questions (FAQ)

Q: Can BK/GMC-750-R, BK1/GMC-750-R, and GMC-750-R be used interchangeably with BK/GMC-750MA?

A: Yes. All three Eaton variants meet the identical electrical and mechanical specifications: 750 mA current rating, 250 V AC voltage rating, 5mm x 20mm package, medium-blow response, and 0.213 Ohms DC cold resistance. These parts are direct functional equivalents.

Q: What is the difference between the Eaton GMC series substitutes and the OptiFuse MSC-750MA?

A: The primary difference is breaking capacity: Eaton GMC parts are rated at 35A, while OptiFuse MSC-750MA is rated at 100A. The melting I²t values are nearly identical (0.85 versus 0.8669). All other electrical parameters are equivalent. The MSC-750MA also provides an extended operating temperature range.

Q: Are there any compatibility issues when substituting the MSC-750MA for the BK/GMC-750MA?

A: No compatibility issues exist for the specified electrical and mechanical parameters. The MSC-750MA maintains the same 750 mA current rating, 250 V AC voltage rating, 5mm x 20mm form factor, and medium-blow response. The higher breaking capacity of the MSC-750MA does not create incompatibility; it provides additional fault current protection margin.

Q: Does the package type affect substitution eligibility?

A: No. All substitute parts use the same 5mm x 20mm glass cartridge package and require the same holder type. Physical installation compatibility is maintained across all alternatives.

Q: What is the significance of the RoHS compliance difference?

A: The obsolete BK/GMC-750MA is RoHS non-compliant, while all active substitutes are ROHS3 compliant. For new designs or systems subject to environmental regulations, ROHS3-compliant alternatives are required. Existing systems using the obsolete part may continue operation, but procurement of new stock requires compliant alternatives.

Q: Can I select any of these substitutes based solely on availability?

A: Yes, for applications where the 35A breaking capacity of the Eaton GMC series is sufficient. If your circuit design requires higher fault current protection, the OptiFuse MSC-750MA with 100A breaking capacity is the appropriate selection. All parts meet the core electrical and mechanical requirements for direct substitution.