Equivalent & Substitute Parts for BK/MDL-12 Glass Cartridge Fuse

Part Overview

The BK/MDL-12 is a 12 A, 32 V AC/DC slow-blow glass cartridge fuse manufactured by Eaton - Electronics Division. This fuse is designed for use in 3AB and 3AG holders with dimensions of 1/4" x 1-1/4" (6.35mm x 31.75mm). The main part is classified as obsolete, which necessitates identification of active equivalent and substitute components to maintain circuit protection functionality in existing and new designs. Substitute parts must maintain identical electrical ratings and mechanical compatibility to ensure proper operation within the protected circuit.

Key Parameters

Parameter	Value
Current Rating	12 A
Voltage Rating (AC)	32 V
Fuse Type	Cartridge, Glass
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

Substitute Part Grouping Explanation

Substitution of the BK/MDL-12 is determined by strict equivalence across the following critical parameters:

Current Rating: 12 A (exact match required)
Voltage Rating: 32 V AC (exact match required)
Fuse Type: Cartridge, Glass (exact match required)
Response Time: Slow Blow (exact match required)
Package / Case: 3AB, 3AG, 1/4" x 1-1/4" (exact match required)
Physical Dimensions: 0.250" Dia x 1.250" L (exact match required)

All substitute parts listed maintain these parameters without deviation. Substitutes are grouped into two categories: direct manufacturer equivalents from Eaton - Electronics Division and parametric equivalents from Littelfuse Inc. All substitute parts are currently in active product status, providing long-term availability compared to the obsolete main part.

Parameter Comparison

Part Number	Manufacturer	Current Rating (A)	Voltage Rating (V AC)	Fuse Type	Response Time	Package / Case	Size (Dia x L)	Product Status	RoHS Status
BK/MDL-12	Eaton - Electronics Division	12	32	Cartridge, Glass	Slow Blow	3AB, 3AG, 1/4" x 1-1/4"	0.250" x 1.250" (6.35mm x 31.75mm)	Obsolete	RoHS non-compliant
BK/MDL-12-R	Eaton - Electronics Division	12	32	Cartridge, Glass	Slow Blow	3AB, 3AG, 1/4" x 1-1/4"	0.250" x 1.250" (6.35mm x 31.75mm)	Active	ROHS3 Compliant
BK/MDQ-12	Eaton - Electronics Division	12	32	Cartridge, Glass	Slow Blow	3AB, 3AG, 1/4" x 1-1/4"	0.250" x 1.250" (6.35mm x 31.75mm)	Active	RoHS non-compliant
0313012.HXP	Littelfuse Inc.	12	32	Cartridge, Glass	Slow Blow	3AB, 3AG, 1/4" x 1-1/4"	0.250" x 1.250" (6.35mm x 31.75mm)	Active	ROHS3 Compliant
0313012.MXP	Littelfuse Inc.	12	32	Cartridge, Glass	Slow Blow	3AB, 3AG, 1/4" x 1-1/4"	0.250" x 1.250" (6.35mm x 31.75mm)	Active	ROHS3 Compliant
0313012.VXP	Littelfuse Inc.	12	32	Cartridge, Glass	Slow Blow	3AB, 3AG, 1/4" x 1-1/4"	0.250" x 1.250" (6.35mm x 31.75mm)	Active	ROHS3 Compliant

Engineering Selection Recommendations

BK/MDL-12-R is the primary substitute for the obsolete BK/MDL-12. Both parts are manufactured by Eaton - Electronics Division, ensuring design continuity and supply chain consistency. BK/MDL-12-R is active in production and achieves ROHS3 compliance, addressing regulatory requirements for new designs and replacements in regulated applications.

BK/MDQ-12 is an active Eaton equivalent that maintains all electrical and mechanical parameters. This part remains available in high inventory and serves as an alternative within the Eaton product family.

0313012.HXP, 0313012.MXP, and 0313012.VXP are parametric equivalents manufactured by Littelfuse Inc. All three parts are active, ROHS3 compliant, and carry UL approval with specified breaking capacity (300A) and melting I²t (1200). These parts are suitable for applications requiring third-party manufacturer options or where Littelfuse supply chain integration is preferred.

Selection between Eaton and Littelfuse substitutes depends on existing supply chain relationships, procurement policies, and application-specific requirements. All listed substitutes are electrically and mechanically interchangeable with the main part.

Frequently Asked Questions (FAQ)

Q: Can BK/MDL-12-R be used as a direct replacement for the obsolete BK/MDL-12?

A: Yes. BK/MDL-12-R maintains identical electrical ratings (12 A, 32 V AC), fuse type (cartridge, glass), response time (slow blow), and mechanical dimensions (1/4" x 1-1/4"). Both parts require the same 3AB and 3AG holders. The primary difference is product status (active vs. obsolete) and RoHS compliance (ROHS3 vs. non-compliant).

Q: What is the difference between Eaton and Littelfuse substitute parts?

A: All substitute parts maintain identical core electrical and mechanical specifications. Littelfuse parts (0313012.HXP, 0313012.MXP, 0313012.VXP) provide additional technical data including breaking capacity (300A), melting I²t (1200), operating temperature range (-55°C to 125°C), and DC cold resistance (0.0065 Ohms). Selection depends on manufacturer preference and supply chain requirements.

Q: Are all substitute parts compatible with existing 3AB and 3AG holders?

A: Yes. All substitute parts are specified for 3AB and 3AG holders with identical physical dimensions of 0.250" diameter x 1.250" length (6.35mm x 31.75mm). No holder modifications are required.

Q: Which substitute part offers the best compliance for new designs?

A: BK/MDL-12-R, 0313012.HXP, 0313012.MXP, and 0313012.VXP all achieve ROHS3 compliance. BK/MDL-12-R maintains Eaton manufacturing continuity, while Littelfuse parts provide UL approval and extended technical specifications.

Q: Is there a difference in response time between substitute parts?

A: No. All substitute parts are specified as slow-blow fuses with identical response characteristics to the main part.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message