SCHURTER 3-103-124 Surface Mount Fuse – Equivalent & Substitute Parts

Part Overview

The SCHURTER 3-103-124 is a 3 A, 125 V AC/DC surface mount board fuse in 2-SMD square end block package format. This fast-blow fuse is designed for board-level protection in applications requiring compact, high-reliability overcurrent protection. The part is active in production with full RoHS3 compliance and cURus/UL approval certifications. Equivalent and substitute parts are identified to support procurement flexibility, inventory optimization, and design continuity across manufacturing revisions.

Substiute Parts

3-103-124

SCHURTER Inc.In Stock: 11403-103-124 Datasheet

Current PartRFQ

3410.0037.02

SCHURTER Inc.In Stock: 211923410.0037.02 Datasheet

UpgradeRFQ

3410.0037.03

SCHURTER Inc.In Stock: 37413410.0037.03 Datasheet

UpgradeRFQ

3-103-122

SCHURTER Inc.In Stock: 18353-103-122 Datasheet

Parametric EquivalentRFQ

3-103-123

SCHURTER Inc.In Stock: 31803-103-123 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SCHURTER 3-103-124 is determined by the following critical parameters:

• Current Rating: 3 A (exact match required)
• Voltage Rating: 125 V AC and 125 V DC (exact match required)
• Response Time: Fast Blow (exact match required)
• Package / Case: 2-SMD, Square End Block (exact match required)
• Mounting Type: Surface Mount (exact match required)
• Breaking Capacity: 50 A AC, 300 A DC (exact match required)
• Physical Dimensions: 0.126" L x 0.061" W x 0.061" H (exact match required)
• RoHS3 Compliance: Required for all substitutes
• Approval Certifications: cURus and/or UL approval required

Substitute parts are classified into two categories:

Upgrade Substitutes (3410.0037.02, 3410.0037.03): These parts share identical electrical and mechanical specifications with the main part but feature extended operating temperature range (-55°C ~ 150°C versus -55°C ~ 125°C) and improved melting I²t characteristics (0.18 versus 0.09). These represent functional upgrades with enhanced thermal performance.

Parametric Equivalents (3-103-122, 3-103-123): These parts maintain identical electrical and mechanical specifications as the main part, with differences limited to packaging format (Cut Tape versus Tape & Reel) and inventory availability. Both retain the same series designation (MGA-A) and thermal specifications.

Parameter Comparison

Engineering Selection Recommendations

All substitute parts listed maintain active production status with full RoHS3 compliance and appropriate regulatory certifications (cURus and/or UL). Selection between the main part and substitutes should be based on the following criteria:

For 3-103-124 (Main Part): Select when dual cURus/UL certification is required and operating temperature does not exceed 125°C. Tape & Reel packaging is suitable for high-volume automated assembly.

For 3410.0037.02 and 3410.0037.03 (Upgrade Substitutes): Select when extended operating temperature range (-55°C ~ 150°C) is required or when improved thermal characteristics (melting I²t of 0.18) are specified. Both parts carry cURus certification. Tape & Reel packaging supports automated assembly processes.

For 3-103-122 and 3-103-123 (Parametric Equivalents): Select when Cut Tape packaging is preferred for lower-volume applications or manual assembly processes. Both parts maintain identical electrical and thermal specifications to the main part with dual cURus/UL certification.

All parts are electrically and mechanically interchangeable within their respective groupings, with no design modifications required for PCB layout or assembly procedures.

Frequently Asked Questions (FAQ)

Q: Can I substitute 3410.0037.02 or 3410.0037.03 for the 3-103-124 in my design?

A: Yes. Both upgrade substitutes share identical electrical ratings (3 A, 125 V AC/DC), response time (Fast Blow), package format (2-SMD, Square End Block), and physical dimensions. The primary differences are extended operating temperature range (-55°C ~ 150°C versus -55°C ~ 125°C) and improved melting I²t (0.18 versus 0.09). These represent functional enhancements with no design modifications required.

Q: What is the difference between Tape & Reel and Cut Tape packaging?

A: Tape & Reel (TR) packaging is supplied on continuous carrier tape wound on reels, optimized for high-speed automated pick-and-place assembly. Cut Tape (CT) packaging is supplied as individual tape segments, suitable for lower-volume applications or manual assembly processes. Electrical and mechanical specifications are identical between packaging formats.

Q: Are all substitute parts certified to the same standards as the 3-103-124?

A: The main part (3-103-124) and parametric equivalents (3-103-122, 3-103-123) carry dual cURus and UL certifications. The upgrade substitutes (3410.0037.02, 3410.0037.03) carry cURus certification. All parts are RoHS3 compliant and suitable for regulated applications.

Q: Can I use 3-103-122 or 3-103-123 interchangeably with 3-103-124 on the same PCB?

A: Yes. Both parametric equivalents are electrically and mechanically identical to the main part. The only differences are packaging format (Cut Tape versus Tape & Reel) and inventory availability. No PCB layout or assembly procedure modifications are required.

Q: What does melting I²t represent, and why does it differ between parts?

A: Melting I²t is a thermal characteristic that defines the fuse's energy absorption capacity before melting. The main part and parametric equivalents have melting I²t of 0.09, while upgrade substitutes have 0.18. Higher melting I²t provides improved thermal performance in applications with transient current spikes. Selection depends on application-specific thermal requirements.

Q: Are there any temperature-related limitations when selecting between these parts?

A: The main part (3-103-124) and parametric equivalents (3-103-122, 3-103-123) are rated for -55°C ~ 125°C operation. The upgrade substitutes (3410.0037.02, 3410.0037.03) extend this range to -55°C ~ 150°C. Select upgrade substitutes if your application requires operation above 125°C.