Equivalent & Substitute Parts for 37FB4420

Part Overview

The 37FB4420 is a 20 µF film capacitor manufactured by Cornell Dubilier Electronics (CDE) rated for 440V AC operation. This radial, metallized polypropylene capacitor is designed for motor run and power factor correction (PFC) applications in industrial and commercial equipment. The part is currently active in production with 796 units in stock. Substitute parts are identified to provide alternative sourcing options when the primary part is unavailable or when design requirements permit equivalent electrical and mechanical specifications.

Substiute Parts

37FB4420

Cornell Dubilier Electronics (CDE)In Stock: 88037FB4420 Datasheet

Current PartRFQ

C878BF35200SA0J

KEMETIn Stock: 1389C878BF35200SA0J Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 37FB4420 is determined by the following critical parameters:

Primary Substitution Criteria:

• Capacitance value: 20 µF (exact match required)
• Dielectric material: Polypropylene (PP), Metallized (exact match required)
• Package configuration: Radial, Can (exact match required)
• Voltage rating: Minimum 440V AC (equal or higher acceptable)
• Tolerance: ±10% or tighter (±5% acceptable as improvement)

Secondary Compatibility Factors:

• Mounting type: Chassis mount configurations
• Termination style: Quick Connect compatible
• Operating temperature range: Must support application requirements
• RoHS and REACH compliance status for regulatory environments

The substitute part C878BF35200SA0J meets the primary substitution criteria with the following considerations: identical capacitance and dielectric material, higher voltage rating (470V AC vs. 440V AC), improved tolerance (±5% vs. ±10%), and ROHS3 compliance. Mechanical dimensions and lead spacing differ but remain compatible with standard chassis mount applications.

Parameter Comparison

Engineering Selection Recommendations

Primary Part Selection (37FB4420): Select the 37FB4420 when the original design specification explicitly requires the CDE MPF series, when RoHS non-compliance is acceptable for the application, or when the specific mechanical dimensions and lead spacing are critical to the circuit board layout.

Substitute Part Selection (C878BF35200SA0J): Select the C878BF35200SA0J when:

• ROHS3 compliance is required for the end application
• Higher voltage rating (470V AC) provides additional design margin
• Tighter tolerance (±5%) improves circuit performance
• Wider operating temperature range (-25°C to 85°C) accommodates environmental requirements
• Mechanical dimensions can be accommodated in the chassis mount assembly

Both parts are active products with current inventory availability. The substitute part offers improved regulatory compliance and electrical specifications while maintaining functional equivalence for motor run and PFC applications.

Frequently Asked Questions (FAQ)

Q: Can C878BF35200SA0J be used as a direct replacement for 37FB4420 in existing equipment?

A: Electrical substitution is valid based on matching capacitance (20 µF), dielectric material (PP metallized), and package type (radial can). Mechanical installation requires verification of the mounting bracket and lead spacing compatibility. The substitute's 470V rating exceeds the 440V requirement, and ±5% tolerance is tighter than the original ±10%.

Q: What are the key differences between these two parts?

A: The primary differences are: voltage rating (470V vs. 440V), tolerance (±5% vs. ±10%), operating temperature range (-25°C to 85°C vs. -40°C to 70°C), RoHS compliance status (ROHS3 vs. non-compliant), and physical dimensions. Electrical performance for motor run and PFC applications remains equivalent.

Q: Are the physical dimensions compatible with existing circuit board layouts?

A: The 37FB4420 measures 2.906" L x 1.906" W with 3.250" seated height and 0.813" lead spacing. The C878BF35200SA0J measures 1.772" diameter with 3.150" seated height and 0.528" lead spacing. Mechanical compatibility depends on the specific chassis mount bracket design and must be verified during integration.

Q: Which part should be selected for new designs?

A: For new designs, the C878BF35200SA0J is preferred when regulatory compliance (ROHS3) is required. Both parts are active products suitable for production use. Selection should be based on compliance requirements, mechanical space constraints, and sourcing availability.

Q: Are there any temperature range limitations to consider?

A: The 37FB4420 operates from -40°C to 70°C, while the C878BF35200SA0J operates from -25°C to 85°C. If the application requires operation below -25°C, the original 37FB4420 is required. For standard industrial motor run and PFC applications, both ranges are typically adequate.

Q: What is the impact of tolerance differences on circuit performance?

A: The ±5% tolerance of C878BF35200SA0J is tighter than the ±10% tolerance of 37FB4420. For power factor correction circuits, tighter tolerance generally improves correction accuracy. For motor run applications, both tolerances are acceptable. Specific circuit requirements should be evaluated during design review.