MDL-3/10-R Equivalent & Substitute Parts Reference

Part Overview

The MDL-3/10-R is a 300 mA, 250 V AC/DC glass cartridge fuse manufactured by Eaton - Electronics Division. This slow-blow fuse is designed for applications requiring circuit protection in the 3AB and 3AG holder formats with dimensions of 1/4" x 1-1/4" (6.35mm x 31.75mm). The part maintains Active product status with 637 units in current inventory. Identifying equivalent and substitute parts is necessary to ensure supply chain continuity, optimize procurement options, and maintain design flexibility across manufacturing environments where multiple qualified suppliers may be required.

Substiute Parts

MDL-3/10-R

Eaton - Electronics DivisionIn Stock: 733MDL-3/10-R Datasheet

Current PartRFQ

BK/MDL-3/10-R

Eaton - Electronics DivisionIn Stock: 1402BK/MDL-3/10-R Datasheet

DirectRFQ

0034.5215

SCHURTER Inc.In Stock: 13780034.5215 Datasheet

Parametric EquivalentRFQ

0313.300HXP

Littelfuse Inc.In Stock: 9950313.300HXP Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the MDL-3/10-R are qualified based on strict electrical and mechanical parameter alignment. The following criteria determine substitutability:

Primary Substitution Criteria:

• Current Rating: 300 mA (exact match required)
• Voltage Rating (AC): 250 V (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)
• Breaking Capacity @ Rated Voltage: 35 A (exact match required)
• Size / Dimension: 0.250" Dia x 1.250" L (exact match required)
• Mounting Type: Requires Holder (exact match required)

Identified Substitute Parts:

1. BK/MDL-3/10-R (Eaton - Electronics Division) – Direct manufacturer equivalent with identical electrical and mechanical specifications. Differs in RoHS status (ROHS3 Compliant vs. RoHS Compliant) and MSL rating (1 Unlimited vs. Not Applicable).

2. 0313.300HXP (Littelfuse Inc.) – Parametric equivalent meeting all primary substitution criteria. Series 313. Active product status. Differs in DC Cold Resistance (3.135 Ohms vs. 2.046 Ohms) and Melting I²t (0.73 vs. 0.412).

3. 0034.5215 (SCHURTER Inc.) – Parametric equivalent meeting all primary substitution criteria. Series FST 6.3x32. Obsolete product status. Differs in Melting I²t (1.27 vs. 0.412) and Operating Temperature range (-55°C ~ 125°C specified).

Parameter Comparison

Engineering Selection Recommendations

Primary Selection: BK/MDL-3/10-R

The BK/MDL-3/10-R is the direct manufacturer equivalent from Eaton - Electronics Division. This part maintains identical electrical and mechanical specifications to the MDL-3/10-R, including current rating, voltage rating, fuse type, response time, package format, breaking capacity, and physical dimensions. Both parts carry CE, CSA, and UL certifications. The BK/MDL-3/10-R holds Active product status with 1334 units in inventory, providing superior supply availability. This part is the preferred substitute for direct replacement applications.

Secondary Selection: 0313.300HXP

The 0313.300HXP from Littelfuse Inc. (Series 313) meets all primary electrical and mechanical substitution criteria. This part maintains Active product status with 957 units in inventory and carries CE, CSA, and UL certifications. The 0313.300HXP differs in DC Cold Resistance (3.135 Ohms versus 2.046 Ohms) and Melting I²t (0.73 versus 0.412). These differences reflect manufacturer-specific thermal characteristics within the same functional class. This part is suitable for applications where multi-source qualification is required.

Tertiary Selection: 0034.5215

The 0034.5215 from SCHURTER Inc. (Series FST 6.3x32) meets all primary electrical and mechanical substitution criteria. However, this part carries Obsolete product status, indicating discontinued manufacturing. While 1283 units remain in current inventory, this part should be selected only when existing stock availability is critical and long-term supply is not required. The 0034.5215 carries CSA and UL certifications (CE certification not listed). The Melting I²t value (1.27) differs significantly from the MDL-3/10-R (0.412), reflecting distinct thermal response characteristics.

Frequently Asked Questions (FAQ)

Q: Can BK/MDL-3/10-R be used as a direct replacement for MDL-3/10-R?

A: Yes. The BK/MDL-3/10-R is a direct manufacturer equivalent with identical electrical specifications (300 mA, 250 V AC), fuse type (Cartridge, Glass), response time (Slow Blow), package format (3AB, 3AG, 1/4" x 1-1/4"), breaking capacity (35 A), and physical dimensions (0.250" Dia x 1.250" L). Both parts are manufactured by Eaton - Electronics Division and carry the same regulatory certifications (CE, CSA, UL).

Q: What is the difference between the MDL-3/10-R and 0313.300HXP?

A: Both parts are electrically and mechanically equivalent with identical current rating (300 mA), voltage rating (250 V AC), fuse type (Cartridge, Glass), response time (Slow Blow), package format (3AB, 3AG, 1/4" x 1-1/4"), and breaking capacity (35 A). The primary differences are manufacturer (Eaton versus Littelfuse), DC Cold Resistance (2.046 Ohms versus 3.135 Ohms), and Melting I²t (0.412 versus 0.73). These differences represent manufacturer-specific thermal design variations within the same functional specification class.

Q: Why is 0034.5215 marked as Obsolete?

A: The 0034.5215 is classified as Obsolete by SCHURTER Inc., indicating that this part number is no longer in active production. While inventory remains available (1283 units), future procurement may become unavailable. This part should be selected only when existing stock is sufficient for project requirements and long-term supply continuity is not a consideration.

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

A: Yes. All substitute parts (BK/MDL-3/10-R, 0313.300HXP, and 0034.5215) are specified for 3AB and 3AG holder formats with identical physical dimensions of 0.250" Dia x 1.250" L (6.35mm x 31.75mm). Physical compatibility with standard 3AB and 3AG fuse holders is confirmed for all listed parts.

Q: Which substitute part has the best long-term availability?

A: The BK/MDL-3/10-R from Eaton - Electronics Division is recommended for long-term availability. This part maintains Active product status with 1334 units in current inventory. The 0313.300HXP (Littelfuse) also maintains Active status with 957 units. The 0034.5215 (SCHURTER) is Obsolete and should not be selected for applications requiring sustained supply.

Q: Do all substitute parts carry the same regulatory certifications?

A: The MDL-3/10-R, BK/MDL-3/10-R, and 0313.300HXP all carry CE, CSA, and UL certifications. The 0034.5215 carries CSA and UL certifications but does not list CE certification. Applications requiring CE compliance should use MDL-3/10-R, BK/MDL-3/10-R, or 0313.300HXP.

Q: What does Melting I²t indicate, and why do the values differ?

A: Melting I²t is a thermal characteristic that describes the fuse's energy absorption capacity before melting. The MDL-3/10-R has a Melting I²t of 0.412, while substitute parts vary (BK/MDL-3/10-R: 0.412, 0313.300HXP: 0.73, 0034.5215: 1.27). These differences reflect manufacturer-specific thermal design. All parts maintain the same current rating (300 mA) and response time (Slow Blow), ensuring functional equivalence in standard circuit protection applications.