Equivalent & Substitute Parts for MDA-1/2-R Ceramic Cartridge Fuse

Part Overview

The MDA-1/2-R is a 500 mA, 250 V AC ceramic cartridge fuse manufactured by Eaton - Electronics Division. This slow-blow fuse is designed for applications requiring overcurrent protection in 3AB and 3AG holder configurations with 1/4" x 1-1/4" dimensions. The part maintains Active product status with 655 units in current inventory. Substitute parts are identified to provide alternative sourcing options while maintaining electrical and mechanical compatibility within the specified parameter envelope.

Substiute Parts

MDA-1/2-R

Eaton - Electronics DivisionIn Stock: 702MDA-1/2-R Datasheet

Current PartRFQ

BK/MDA-1/2-R

Eaton - Electronics DivisionIn Stock: 891BK/MDA-1/2-R Datasheet

DirectRFQ

0001.2521

SCHURTER Inc.In Stock: 20440001.2521 Datasheet

DirectRFQ

0326.500MXP

Littelfuse Inc.In Stock: 19400326.500MXP Datasheet

DirectRFQ

0326.500HXP

Littelfuse Inc.In Stock: 14090326.500HXP Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility is determined by strict alignment with the following critical parameters:

Primary Compatibility Criteria:

• Current Rating: 500 mA (exact match required)
• Voltage Rating - AC: 250 V (exact match required)
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4" (exact match required)
• Mounting Type: Requires Holder (exact match required)
• Response Time: Slow Blow (exact match required)

Secondary Compatibility Criteria:

• Fuse Type: Cartridge construction (ceramic or glass acceptable)
• Size / Dimension: 0.250" Dia x 1.250" L ±0.002" (mechanical fit requirement)
• Approval Agency: CE, CSA, UL or cURus certification required

Substitutes are grouped as follows:

Group 1 - Direct Manufacturer Equivalent (Eaton): BK/MDA-1/2-R meets all primary and secondary criteria with identical electrical and mechanical specifications.

Group 2 - Cross-Manufacturer Ceramic Cartridge Fuses (Littelfuse): 0326.500MXP and 0326.500HXP meet all primary criteria. Both are ceramic cartridge fuses with 500 mA, 250 V AC rating in 3AB/3AG package. Extended DC voltage rating (125 V) and broader operating temperature range (-55°C ~ 125°C) provide enhanced capability margins.

Group 3 - Cross-Manufacturer Glass Cartridge Fuse (SCHURTER): 0001.2521 meets primary current, AC voltage, and package criteria. Glass construction differs from ceramic; DC voltage rating (63 V) and breaking capacity specifications differ from ceramic alternatives.

Parameter Comparison

Engineering Selection Recommendations

BK/MDA-1/2-R (Eaton - Electronics Division)

This part is the direct manufacturer equivalent of MDA-1/2-R. Both parts are manufactured by Eaton and share identical electrical specifications, package configuration, and approval certifications (CE, CSA, UL). Selection of BK/MDA-1/2-R is appropriate when Eaton sourcing is required or when inventory availability of the primary part number is constrained. Current inventory: 844 units.

0326.500MXP and 0326.500HXP (Littelfuse Inc.)

Both Littelfuse parts meet all primary substitution criteria with 500 mA, 250 V AC rating in 3AB/3AG package. These ceramic cartridge fuses carry CE, CSA, and UL approvals. Extended DC voltage rating (125 V) and operating temperature range (-55°C ~ 125°C) exceed the specifications of MDA-1/2-R. Selection is appropriate for applications requiring enhanced DC voltage capability or extended temperature operation. Both parts are parametrically equivalent; selection between them is based on inventory availability (0326.500MXP: 1881 units; 0326.500HXP: 1397 units).

0001.2521 (SCHURTER Inc.)

This glass cartridge fuse meets primary current, AC voltage, and package criteria. The glass construction differs from the ceramic design of MDA-1/2-R. Approval certification is cURus (combined UL and CSA). DC voltage rating is 63 V with significantly higher breaking capacity (1.5kA AC, 20kA DC) and lower melting I²t (0.3). Selection is appropriate for applications where glass construction is acceptable and where the specified breaking capacity and melting characteristics align with circuit protection requirements. Current inventory: 1971 units.

Frequently Asked Questions (FAQ)

Q: Can BK/MDA-1/2-R be used as a direct replacement for MDA-1/2-R?

A: Yes. BK/MDA-1/2-R is the direct manufacturer equivalent produced by Eaton - Electronics Division. Both parts share identical current rating (500 mA), AC voltage rating (250 V), fuse type (ceramic cartridge), response time (slow blow), and package configuration (3AB, 3AG, 1/4" x 1-1/4"). Approval certifications are identical (CE, CSA, UL). Substitution is direct.

Q: What is the difference between the Littelfuse 0326.500MXP and 0326.500HXP?

A: Both parts are parametrically equivalent ceramic cartridge fuses with identical electrical ratings (500 mA, 250 V AC, 125 V DC), package configuration, and approvals. The designation difference reflects internal design variations. Selection between them is based on inventory availability and application-specific requirements. Both are suitable substitutes for MDA-1/2-R.

Q: Can the SCHURTER 0001.2521 glass fuse replace the ceramic MDA-1/2-R?

A: The 0001.2521 meets the primary electrical criteria (500 mA, 250 V AC) and package requirements (3AB, 3AG, 1/4" x 1-1/4"). However, it differs in fuse construction (glass versus ceramic), DC voltage rating (63 V versus not specified), and melting characteristics (I²t of 0.3 versus 1.2). Substitution is permissible only when the application circuit protection requirements align with the glass fuse's specified breaking capacity and melting characteristics.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. MDA-1/2-R, BK/MDA-1/2-R, 0326.500MXP, 0326.500HXP, and 0001.2521 are all ROHS3 compliant.

Q: What approval certifications are required for these fuses?

A: MDA-1/2-R, BK/MDA-1/2-R, 0326.500MXP, and 0326.500HXP carry CE, CSA, and UL approvals. The SCHURTER 0001.2521 carries cURus certification (combined UL and CSA approval). All parts meet recognized safety standards for cartridge fuse applications.

Q: Do all substitute parts fit in 3AB and 3AG holders?

A: Yes. All substitute parts are specified for 3AB and 3AG holder configurations with 1/4" x 1-1/4" package dimensions. The SCHURTER 0001.2521 has a length specification of 0.250" Dia x 1.252" L, which is within acceptable mechanical tolerance for holder compatibility.

Q: What is the significance of the melting I²t parameter?

A: Melting I²t defines the thermal energy required to melt the fuse element. MDA-1/2-R has I²t of 1.2; BK/MDA-1/2-R has 2.6; Littelfuse parts have 2.5; SCHURTER has 0.3. Lower I²t values indicate faster response to overcurrent. Selection must align with circuit protection requirements and inrush current characteristics of the protected equipment.

Q: What is the DC cold resistance specification used for?

A: DC cold resistance (measured at room temperature with no current flowing) affects voltage drop across the fuse during normal operation. MDA-1/2-R: 2.6 Ohms; BK/MDA-1/2-R: 1.2 Ohms; Littelfuse parts: 1.3 Ohms. Lower resistance reduces power dissipation and heat generation in the fuse element.