Equivalent & Substitute Parts for MDQ-3/8 Glass Cartridge Fuse

Part Overview

The MDQ-3/8 is a 375 mA, 250 V AC/DC slow-blow glass cartridge fuse manufactured by Eaton - Electronics Division. This component is classified as Active and requires a 3AB or 3AG fuse holder for installation. The fuse is designed for circuit protection applications requiring slow-blow response characteristics and is housed in a 1/4" x 1-1/4" (6.35mm x 31.75mm) cylindrical glass cartridge format.

Substitute parts are necessary when the primary MDQ-3/8 is unavailable due to inventory constraints, supply chain disruptions, or when alternative manufacturers' components meet identical electrical and mechanical specifications for direct replacement in existing designs.

Substiute Parts

MDQ-3/8

Eaton - Electronics DivisionIn Stock: 970MDQ-3/8 Datasheet

Current PartRFQ

BK/MDL-3/8-R

Eaton - Electronics DivisionIn Stock: 1206BK/MDL-3/8-R Datasheet

Parametric EquivalentRFQ

0034.5217

SCHURTER Inc.In Stock: 9910034.5217 Datasheet

Parametric EquivalentRFQ

0313.375HXP

Littelfuse Inc.In Stock: 10580313.375HXP Datasheet

Parametric EquivalentRFQ

0313.375MXP

LittelfuseIn Stock: 37180313.375MXP Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MDQ-3/8 is determined by strict equivalence across the following parameters:

Critical Matching Parameters:

• Current Rating: 375 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)

All substitute parts listed below meet these critical parameters and are therefore electrically and mechanically interchangeable with the MDQ-3/8 in applications requiring 375 mA, 250 V AC/DC slow-blow fuse protection with 3AB/3AG holder compatibility.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Active Status):

The BK/MDL-3/8-R, 0313.375HXP, and 0313.375MXP are recommended as primary substitutes for the MDQ-3/8. All three parts maintain Active product status and carry CE, CSA, and UL approvals, ensuring continued availability and regulatory compliance. The BK/MDL-3/8-R is manufactured by Eaton - Electronics Division, the same manufacturer as the primary part, providing design continuity. The Littelfuse parts (0313.375HXP and 0313.375MXP) are from an established alternative manufacturer with equivalent certifications.

Secondary Substitute (Obsolete Status):

The 0034.5217 manufactured by SCHURTER Inc. meets all electrical and mechanical parameters but carries Obsolete product status. This part is suitable for substitution only when Active alternatives are unavailable and existing inventory is confirmed.

Compliance Considerations:

All substitute parts are RoHS3 compliant and REACH unaffected, maintaining environmental and regulatory alignment with the original MDQ-3/8 specification.

Frequently Asked Questions (FAQ)

Q: Can the BK/MDL-3/8-R be used as a direct replacement for the MDQ-3/8?

A: Yes. The BK/MDL-3/8-R is a parametric equivalent with identical current rating (375 mA), voltage rating (250 V AC), response time (Slow Blow), package format (3AB, 3AG, 1/4" x 1-1/4"), and breaking capacity (35 A). Both are manufactured by Eaton - Electronics Division and carry CSA and UL approvals.

Q: What is the difference between the Littelfuse 0313.375HXP and 0313.375MXP?

A: Both parts are parametrically equivalent to the MDQ-3/8 and to each other across all critical electrical and mechanical parameters. Both carry Active product status and identical certifications (CE, CSA, UL). Selection between these two parts is based on inventory availability and supply chain considerations.

Q: Why is the SCHURTER 0034.5217 listed as a substitute if it is Obsolete?

A: The 0034.5217 meets all electrical and mechanical substitution criteria and remains available in inventory. Obsolete status indicates the manufacturer has discontinued production, but existing stock remains suitable for applications requiring 375 mA, 250 V AC/DC slow-blow fuse protection with 3AB/3AG holder compatibility.

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

A: Yes. All substitute parts are specified for 3AB and 3AG holder compatibility with identical 1/4" x 1-1/4" (6.35mm x 31.75mm) dimensions, ensuring mechanical fit and electrical connection in existing holder installations.

Q: What certifications do the substitute parts carry?

A: The BK/MDL-3/8-R, 0313.375HXP, and 0313.375MXP carry CE, CSA, and UL approvals. The 0034.5217 carries CSA and UL approvals. The original MDQ-3/8 carries CSA and UL approvals. All parts meet required regulatory standards for circuit protection applications.

Q: Can substitute parts be mixed in the same application?

A: Yes. All substitute parts meet identical electrical and mechanical specifications and are therefore interchangeable within the same application circuit. Holder compatibility and fuse rating requirements remain consistent across all listed parts.