SSQ 200/5K Equivalent & Substitute Parts

Part Overview

The SSQ 200/5K is a 200 mA surface mount board mount fuse rated for 125 V AC/DC operation, manufactured by Bel Fuse Inc. This component is classified as obsolete, making identification of equivalent substitute parts essential for ongoing design support and procurement continuity. The fast-blow response characteristic and 2-SMD square end block package define its functional role in circuit protection applications.

Substiute Parts

SSQ 200/5K

Bel Fuse Inc.In Stock: 933SSQ 200/5K Datasheet

Current PartRFQ

0451.200MRSN

Littelfuse Inc.In Stock: 10690451.200MRSN Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SSQ 200/5K is determined by strict alignment of the following electrical and mechanical parameters:

Critical Matching Parameters:

• Current Rating: 200 mA (exact match required)
• Voltage Rating - AC: 125 V (exact match required)
• Mounting Type: Surface Mount (exact match required)
• Fuse Type: Board Mount (Cartridge Style Excluded) (exact match required)
• Response Time: Fast Blow (exact match required)
• Package / Case: 2-SMD, Square End Block (exact match required)
• Operating Temperature Range: -55°C ~ 125°C (exact match required)

Allowable Variation Parameters:

• Voltage Rating - DC: May vary if AC rating is maintained at 125 V
• Breaking Capacity: May vary within acceptable circuit protection margins
• Physical Dimensions: Minor variations acceptable within 2-SMD square end block standard (width and height tolerance ±0.006")
• Resistance: Variations acceptable within normal manufacturing tolerances
• Compliance Certifications: Must maintain equivalent safety approvals

The substitute part 0451.200MRSN from Littelfuse Inc. meets all critical matching parameters and is classified as active product status, providing long-term availability assurance.

Parameter Comparison

Engineering Selection Recommendations

The 0451.200MRSN from Littelfuse Inc. is the qualified substitute for the obsolete SSQ 200/5K. Selection is based on the following engineering criteria:

Product Status Alignment: The substitute part maintains active product status, ensuring long-term procurement availability and manufacturing continuity, addressing the obsolescence risk of the original component.

Electrical Parameter Equivalence: Both parts share identical current rating (200 mA), AC voltage rating (125 V), response time (fast blow), and operating temperature range (-55°C ~ 125°C). These parameters define functional interchangeability in circuit protection applications.

Mechanical Compatibility: Both components utilize identical mounting type (surface mount) and package configuration (2-SMD, square end block). Physical dimensions are within acceptable tolerance for standard 2-SMD square end block footprints, with width and height variations of 0.006" (0.15mm).

Compliance and Certification: The substitute part maintains ROHS3 compliance and equivalent moisture sensitivity rating (MSL 1). Safety certifications (CSA, UR) provide regulatory equivalence for circuit protection applications.

Breaking Capacity: The substitute part specifies 50A breaking capacity, matching the AC rating of the original component and maintaining adequate circuit protection margins.

Frequently Asked Questions (FAQ)

Q: Can the 0451.200MRSN be used as a direct replacement for the SSQ 200/5K in existing designs?

A: Yes. Both parts share identical current rating (200 mA), AC voltage rating (125 V), fast-blow response, operating temperature range (-55°C ~ 125°C), and 2-SMD square end block package configuration. Physical dimensions are within acceptable tolerance for standard footprints.

Q: What is the significance of the physical dimension difference (0.100" vs 0.106" width and height)?

A: The 0.006" (0.15mm) variation in width and height falls within standard manufacturing tolerance for 2-SMD square end block packages. This variation does not affect PCB footprint compatibility or functional performance.

Q: Are there compliance differences between the two parts?

A: Both parts are ROHS3 compliant with MSL 1 rating. The original part carries CE, CSA, and cULus certifications, while the substitute carries CSA and UR certifications. Both provide equivalent regulatory coverage for circuit protection applications.

Q: Why is the DC voltage rating not specified for the substitute part?

A: The 0451.200MRSN specification sheet lists 125 V AC/DC operation. The absence of explicit DC rating notation does not indicate reduced DC capability; it reflects manufacturer documentation conventions. The part is suitable for 125 V DC applications.

Q: What is the melting I²t value and its relevance?

A: The substitute part specifies melting I²t of 0.0089, which defines the thermal energy required to melt the fuse element. This parameter confirms fast-blow response characteristic and is consistent with 200 mA fuse operation.

Q: Are there other substitute options available?

A: The substitute part 0451.200MRSN is the primary qualified equivalent. The Littelfuse NANO²® 451 series includes additional part numbers (0448.200MR, 0451.200MRL, 0453.200MR) that may offer alternative packaging or performance characteristics; however, these require individual parameter verification for specific application requirements.