SFS37S40K288B-F Equivalent & Substitute Parts

Part Overview

The SFS37S40K288B-F is a 40 µF film capacitor rated for 370V AC operation, manufactured by Cornell Dubilier Electronics (CDE). This polypropylene metallized radial capacitor is designed for motor run applications with a chassis mount configuration requiring a holder or bracket. The part is currently listed as obsolete, necessitating identification of equivalent and substitute components for continued system support and procurement.

Substiute Parts

SFS37S40K288B-F

Cornell Dubilier Electronics (CDE)In Stock: 945SFS37S40K288B-F Datasheet

Current PartRFQ

SFS37T40K291B-F

Cornell Dubilier Electronics (CDE)In Stock: 1117SFS37T40K291B-F Datasheet

DirectRFQ

SFS37S40K288B

Cornell Dubilier Electronics (CDE)In Stock: 753SFS37S40K288B Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SFS37S40K288B-F is determined by strict equivalence across the following electrical and mechanical parameters:

Electrical Equivalence Criteria:

• Capacitance: 40 µF (exact match required)
• Tolerance: ±10% (exact match required)
• Voltage Rating (AC): 370V (exact match required)
• Dielectric Material: Polypropylene (PP), Metallized (exact match required)
• Operating Temperature Range: -40°C ~ 70°C (exact match required)

Mechanical Equivalence Criteria:

• Package Type: Radial, Can (exact match required)
• Mounting Type: Chassis Mount, Requires Holder/Bracket (exact match required)
• Lead Spacing: 0.810" (20.57mm) (exact match required)
• Physical Dimensions: 2.120" Dia (53.85mm) (exact match required)

Termination Compatibility:

• Quick Connect, Disconnect (exact match required)

Substitute parts are grouped into two categories: Direct Manufacturer Substitutes (same manufacturer, active product status) and Parametric Equivalents (same electrical and mechanical specifications, alternative compliance status).

Parameter Comparison

Engineering Selection Recommendations

SFS37T40K291B-F (Direct Manufacturer Substitute - Recommended)

The SFS37T40K291B-F is the primary substitute for the obsolete SFS37S40K288B-F. This part maintains identical electrical specifications (40 µF, ±10%, 370V AC) and mechanical compatibility (radial can package, 0.810" lead spacing, 2.120" diameter). The substitute carries active product status from Cornell Dubilier Electronics, ensuring continued availability and manufacturing support. Both parts are ROHS3 compliant and REACH unaffected. The height difference of 0.030" (0.76mm) between the seated maximum dimensions (3.030" versus 3.000") is within typical mechanical tolerance ranges for chassis-mounted capacitor applications. Packaging is supplied in bulk format.

SFS37S40K288B (Parametric Equivalent - Alternative Option)

The SFS37S40K288B provides parametric equivalence across all electrical and mechanical specifications. This part is active in product status and maintains identical physical dimensions to the main part (3.000" seated height). However, this equivalent is RoHS non-compliant, whereas the main part and primary substitute are ROHS3 compliant. Selection of this part requires verification of regulatory compliance requirements for the end application. This option is suitable only for applications where RoHS compliance is not mandated.

Frequently Asked Questions (FAQ)

Q: Can SFS37T40K291B-F be used as a direct replacement for SFS37S40K288B-F?

A: Yes. The SFS37T40K291B-F meets all electrical and mechanical equivalence criteria. Both parts share identical capacitance (40 µF), tolerance (±10%), voltage rating (370V AC), dielectric material (polypropylene metallized), operating temperature range (-40°C ~ 70°C), package type (radial can), lead spacing (0.810"), and diameter (2.120"). The 0.030" height difference falls within acceptable mechanical tolerances for motor run applications.

Q: What is the difference between the direct substitute and the parametric equivalent?

A: The direct substitute (SFS37T40K291B-F) is an active product from the same manufacturer with ROHS3 compliance. The parametric equivalent (SFS37S40K288B) is also active but is RoHS non-compliant. Both are electrically and mechanically equivalent to the main part. Selection depends on regulatory compliance requirements.

Q: Are there any compatibility concerns with the height difference of the SFS37T40K291B-F?

A: The seated height difference is 0.030" (0.76mm). For chassis-mounted applications using holder or bracket assemblies, this variation is within standard mechanical tolerances and does not affect electrical performance or mechanical fit.

Q: What certifications apply to these substitute parts?

A: All parts carry REACH Unaffected status and EAR99 ECCN classification. The primary substitute (SFS37T40K291B-F) and main part (SFS37S40K288B-F) are ROHS3 compliant. The parametric equivalent (SFS37S40K288B) is RoHS non-compliant.

Q: Can these parts be used interchangeably in motor run applications?

A: Yes. All three parts are specified for motor run applications and maintain identical electrical ratings, dielectric material, and operating temperature ranges. Mechanical compatibility is confirmed through matching lead spacing, package type, and mounting requirements.

Q: What is the lead spacing specification, and why is it important?

A: Lead spacing is 0.810" (20.57mm) for all parts. This specification determines compatibility with circuit board layouts, holder brackets, and terminal connections. Identical lead spacing across all parts ensures direct mechanical and electrical interchangeability.