Equivalent & Substitute Parts for BK/C515-125MA

Part Overview

The BK/C515-125MA is a 125 mA, 250 V AC/DC glass cartridge fuse manufactured by Eaton - Electronics Division. This component is classified as obsolete, indicating that direct procurement from original inventory may become limited. The fuse operates with slow-blow response characteristics and is housed in a 2AG package format (5mm x 15mm axial configuration) suitable for through-hole mounting applications.

Identifying equivalent and substitute parts is necessary to ensure circuit protection continuity when the original part number becomes unavailable or when design revisions require active product status components.

Substiute Parts

BK/C515-125MA

Eaton - Electronics DivisionIn Stock: 1058BK/C515-125MA Datasheet

Current PartRFQ

BK/C515-125-R

Eaton - Electronics DivisionIn Stock: 4239BK/C515-125-R Datasheet

DirectRFQ

BK/C515S-125-R

Eaton - Electronics DivisionIn Stock: 1099BK/C515S-125-R Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the BK/C515-125MA is determined by strict equivalence across the following critical parameters:

Electrical Parameters:

• Current Rating: 125 mA (exact match required)
• Voltage Rating (AC): 250 V (exact match required)
• Response Time: Slow Blow (exact match required)
• Breaking Capacity @ Rated Voltage: 35 A (exact match required)
• Melting I²t: 0.101 (exact match required)
• DC Cold Resistance: 4.72 Ohms (exact match required)

Mechanical Parameters:

• Fuse Type: Cartridge, Glass (exact match required)
• Package / Case: 2AG, 5mm x 15mm (Axial) (exact match required)
• Mounting Type: Through Hole (exact match required)
• Physical Dimensions: 0.217" Dia x 0.598" L (exact match required)

Certification Parameters:

• Approval Agency: CSA, UL (exact match required)

All substitute parts listed below meet these criteria without deviation.

Parameter Comparison

Engineering Selection Recommendations

BK/C515-125-R is the primary direct substitute for BK/C515-125MA. Both parts are manufactured by Eaton - Electronics Division and maintain identical electrical and mechanical specifications. The BK/C515-125-R carries active product status, ensuring ongoing availability and supply chain continuity. This part achieves RoHS compliance, addressing environmental and regulatory requirements that may apply to new designs or manufacturing revisions.

BK/C515S-125-R is a parametric equivalent substitute for BK/C515-125MA. This part maintains all critical electrical and mechanical parameters and also carries active product status with RoHS compliance. The designation variant (S-series) indicates a design revision within the C515 family while preserving functional equivalence.

Both substitute parts carry CSA and UL approval certifications, matching the original part's regulatory qualifications. Selection between BK/C515-125-R and BK/C515S-125-R should be based on design documentation requirements, supply chain preferences, and any specific packaging or logistics considerations.

Frequently Asked Questions (FAQ)

Q: Can BK/C515-125-R be used as a direct replacement for BK/C515-125MA in existing circuit designs?

A: Yes. BK/C515-125-R is electrically and mechanically equivalent to BK/C515-125MA. All critical parameters including current rating, voltage rating, response time, breaking capacity, melting I²t, and physical dimensions are identical. The part is pin-compatible and requires no circuit modifications.

Q: What is the difference between BK/C515-125-R and BK/C515S-125-R?

A: Both parts are parametric equivalents with identical electrical and mechanical specifications. The S-series designation (BK/C515S-125-R) represents a design variant within the C515 family. Both parts maintain the same 125 mA current rating, 250 V voltage rating, slow-blow response, 2AG package format, and all other critical parameters. Selection between these variants should follow design documentation or supply chain guidance.

Q: Why is the original BK/C515-125MA marked as obsolete?

A: Product obsolescence indicates that the original part number is no longer in active production. Substitute parts BK/C515-125-R and BK/C515S-125-R maintain active status, ensuring continued availability and supply chain support.

Q: Are the substitute parts RoHS compliant?

A: Yes. Both BK/C515-125-R and BK/C515S-125-R are RoHS compliant. The original BK/C515-125MA is RoHS non-compliant. This distinction is relevant for applications subject to RoHS regulations or customer requirements.

Q: Do the substitute parts carry the same certifications as the original?

A: Yes. BK/C515-125-R and BK/C515S-125-R both carry CSA and UL approval certifications, matching the original BK/C515-125MA certifications.

Q: Can these fuses be used in both AC and DC circuits?

A: The electrical specifications indicate 250 V AC rating. DC application compatibility is determined by the circuit design and the fuse's DC cold resistance (4.72 Ohms). Consult circuit design documentation and application requirements to confirm DC suitability.

Q: What is the physical package format for these fuses?

A: All three parts use the 2AG package format with axial through-hole mounting. Physical dimensions are 0.217" diameter x 0.598" length (5.50mm x 15.20mm). This format is standard for cartridge glass fuses in this current and voltage class.