SSQ 3 Equivalent & Substitute Parts

Part Overview

The SSQ 3 is a 3 A surface mount board mount fuse rated for 125 V AC/DC operation with fast blow response characteristics. Manufactured by Bel Fuse Inc., this component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The SSQ 3 is packaged in Cut Tape (CT) & Digi-Reel® format with a 2-SMD, Square End Block configuration suitable for automated assembly processes.

Substiute Parts

SSQ 3

Bel Fuse Inc.In Stock: 2148SSQ 3 Datasheet

Current PartRFQ

0679L3000-01

Bel Fuse Inc.In Stock: 1856280679L3000-01 Datasheet

DirectRFQ

0451003.MRL

Littelfuse Inc.In Stock: 302130451003.MRL Datasheet

DirectRFQ

0476003.MR

Littelfuse Inc.In Stock: 21390476003.MR Datasheet

DirectRFQ

0476003.MRSN

Littelfuse Inc.In Stock: 7450476003.MRSN Datasheet

DirectRFQ

0451003.MRSN

Littelfuse Inc.In Stock: 14720451003.MRSN Datasheet

SimilarRFQ

0453003.MR

Littelfuse Inc.In Stock: 566290453003.MR Datasheet

SimilarRFQ

3404.0014.11

SCHURTER Inc.In Stock: 11513404.0014.11 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the SSQ 3 is determined by strict equivalence across the following critical parameters: current rating (3 A), AC voltage rating (125 V), DC voltage rating (125 V), response time (Fast Blow), mounting type (Surface Mount), fuse type (Board Mount), and package configuration (2-SMD, Square End Block). Parts meeting these criteria are classified as direct substitutes. Parts that maintain the same current rating, voltage ratings, and response time but differ in package case style (J-Lead vs. Square End Block) or voltage rating asymmetry are classified as similar substitutes with noted mechanical or electrical variations.

Parameter Comparison

Engineering Selection Recommendations

For direct replacement of the obsolete SSQ 3, the 0679L3000-01 (Bel Fuse Inc.) is the primary equivalent, maintaining identical voltage ratings and package configuration while offering active product status and higher inventory availability. The 0451003.MRL (Littelfuse Inc., NANO²® 451 series) provides an alternative with matching electrical specifications and Cut Tape packaging identical to the original SSQ 3 format.

The 0453003.MR (Littelfuse Inc., NANO²® 453 series) is functionally equivalent with identical voltage ratings and package style, supported by active product status and substantial inventory levels.

Parts 0476003.MR and 0476003.MRSN (Littelfuse Inc., NANO²® 476 series) are suitable for applications requiring higher AC voltage rating (250 V AC) while maintaining 125 V DC and 3 A current specifications. These parts are appropriate only when the design circuit supports the elevated AC voltage rating.

The 3404.0014.11 (SCHURTER Inc., OMF 125 series) maintains equivalent electrical ratings but employs a J-Lead package configuration instead of Square End Block. This part is suitable only for designs with mechanical accommodation for J-Lead geometry.

The 0451003.MRSN (Littelfuse Inc.) lacks specified DC voltage rating in the provided data and should be evaluated for DC circuit applications only after confirming DC voltage compatibility through manufacturer documentation.

Frequently Asked Questions (FAQ)

Q: Can the 0679L3000-01 directly replace the SSQ 3 in existing designs?

A: Yes. The 0679L3000-01 maintains identical current rating (3 A), AC voltage rating (125 V), DC voltage rating (125 V), response time (Fast Blow), and package configuration (2-SMD, Square End Block). The primary difference is packaging format (Tape & Reel vs. Cut Tape & Digi-Reel®), which affects procurement and assembly handling but not electrical or mechanical compatibility.

Q: What is the difference between 0451003.MRL and 0453003.MR?

A: Both parts are 3 A, 125 V AC/DC fast blow fuses in 2-SMD, Square End Block packages from Littelfuse Inc. The primary distinction is series designation (NANO²® 451 vs. NANO²® 453) and melting I²t value (1.65 for both). Selection between these parts depends on design-specific thermal response requirements and packaging format availability (Cut Tape vs. Tape & Reel).

Q: Can 0476003.MR be used in place of SSQ 3?

A: The 0476003.MR is electrically compatible for DC circuits rated at 125 V and AC circuits rated at 250 V. It is suitable only if the design circuit supports the higher 250 V AC rating. Using this part in a 125 V AC circuit is acceptable from an overvoltage margin perspective but represents over-specification.

Q: Why does 3404.0014.11 have a different package case (J-Lead)?

A: The 3404.0014.11 (SCHURTER Inc., OMF 125 series) employs J-Lead termination geometry (0.291" L x 0.122" W x 0.102" H) compared to the Square End Block configuration of the SSQ 3 (0.240" L x 0.100" W x 0.100" H). This part is suitable only for PCB designs with J-Lead pad layouts and mechanical clearance for the larger footprint.

Q: What does "Product Status: Obsolete" mean for the SSQ 3?

A: Obsolete status indicates the SSQ 3 is no longer manufactured or supported by Bel Fuse Inc. New designs should transition to active alternatives such as 0679L3000-01, 0451003.MRL, or 0453003.MR to ensure long-term supply chain continuity and manufacturer technical support.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All substitute parts listed maintain ROHS3 compliance status, consistent with the original SSQ 3 specification.