SEK4R7M400ST Equivalent & Substitute Parts Reference

Part Overview

The SEK4R7M400ST is a 4.7 µF, 400 V aluminum electrolytic capacitor in radial, can package manufactured by Cornell Dubilier Electronics (CDE). This component is classified as Active product status and serves general-purpose applications requiring polar capacitive energy storage at 400 V rated voltage. The SEK series capacitor operates across a temperature range of -40°C to 105°C with a rated lifetime of 2000 hours at 105°C. Equivalent and substitute parts are identified to address inventory availability, extended operational lifetime requirements, or specific packaging preferences while maintaining electrical and mechanical compatibility.

Substiute Parts

SEK4R7M400ST

Cornell Dubilier Electronics (CDE)In Stock: 964SEK4R7M400ST Datasheet

Current PartRFQ

400LLE4.7MEFCT810X12.5

RubyconIn Stock: 3528400LLE4.7MEFCT810X12.5 Datasheet

DirectRFQ

400LLE4R7MEFC10X12.5

RubyconIn Stock: 44118400LLE4R7MEFC10X12.5 Datasheet

DirectRFQ

ULD2G4R7MPD

NichiconIn Stock: 2806ULD2G4R7MPD Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SEK4R7M400ST are qualified based on strict electrical and mechanical parameter alignment. All substitute candidates maintain identical capacitance (4.7 µF), rated voltage (400 V), tolerance (±20%), polarization (Polar), and mounting configuration (Through Hole, Radial Can). Lead spacing (5.00mm) and primary dimension (10.00mm diameter) are preserved across all qualified substitutes to ensure direct board-level compatibility without layout modification.

The substitution logic is based on the following critical parameters:

• Capacitance value: 4.7 µF (exact match required)
• Voltage rating: 400 V (exact match required)
• Tolerance: ±20% (exact match required)
• Package type: Radial, Can (exact match required)
• Lead spacing: 5.00mm (exact match required)
• Can diameter: 10.00mm (exact match required)
• Mounting: Through Hole (exact match required)
• Operating temperature range: -40°C to 105°C (exact match required)
• Polarization: Polar (exact match required)
• RoHS compliance: ROHS3 Compliant (compliance requirement)

Substitute parts may differ in height dimension, lifetime rating at 105°C, ripple current specifications, ESR characteristics, and packaging format (Bulk vs. Cut Tape), provided these variations do not compromise circuit performance or board assembly constraints.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Active Product Status):

The Rubycon LLE series parts (400LLE4.7MEFCT810X12.5 and 400LLE4R7MEFC10X12.5) are qualified as direct substitutes for the SEK4R7M400ST. Both Rubycon alternatives maintain Active product status, ensuring continued availability and manufacturing support. These parts provide extended operational lifetime (15000 hours at 105°C versus 2000 hours for the original part), higher ripple current ratings, and full ROHS3 compliance. The primary distinction between the two Rubycon options is packaging format: 400LLE4.7MEFCT810X12.5 is supplied in Cut Tape (CT) format, while 400LLE4R7MEFC10X12.5 is supplied in Bulk format. Height dimensions differ slightly (14.00mm versus 14.50mm), both remaining within typical PCB clearance specifications.

Secondary Substitute (Legacy Product Status):

The Nichicon ULD2G4R7MPD is electrically and mechanically compatible with the SEK4R7M400ST but carries "Not For New Designs" product status. This part is suitable for replacement applications, repair, or legacy system maintenance only. The ULD2G4R7MPD exhibits REACH Affected compliance status, whereas the primary substitutes and original part are REACH Unaffected. Selection of this part requires design review confirmation that legacy product status is acceptable for the intended application.

Height Dimension Consideration:

The SEK4R7M400ST has a maximum seated height of 16.00mm. All substitute parts have reduced heights (14.00mm to 14.50mm), providing additional PCB clearance. This dimensional reduction is compatible with standard through-hole assembly processes and does not introduce mechanical constraints.

Frequently Asked Questions (FAQ)

Q: Can the Rubycon 400LLE4R7MEFC10X12.5 directly replace the SEK4R7M400ST without PCB modification?

A: Yes. The 400LLE4R7MEFC10X12.5 maintains identical lead spacing (5.00mm), can diameter (10.00mm), capacitance (4.7 µF), voltage rating (400 V), tolerance (±20%), and mounting type (Through Hole, Radial Can). The reduced height (14.50mm versus 16.00mm) provides additional clearance and does not require layout changes.

Q: What is the difference between the two Rubycon substitute parts?

A: Both Rubycon LLE series parts (400LLE4.7MEFCT810X12.5 and 400LLE4R7MEFC10X12.5) are electrically identical. The primary difference is packaging: 400LLE4.7MEFCT810X12.5 is supplied in Cut Tape (CT) format for automated pick-and-place assembly, while 400LLE4R7MEFC10X12.5 is supplied in Bulk format. Height dimensions differ slightly (14.00mm versus 14.50mm). Selection depends on assembly process requirements and available inventory.

Q: Why does the Nichicon ULD2G4R7MPD have "Not For New Designs" status?

A: The ULD2G4R7MPD is classified as legacy product. While electrically and mechanically compatible, this part is not recommended for new circuit designs. It is suitable for replacement of existing installations or repair of legacy systems where the original part is no longer available.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. The SEK4R7M400ST and both active Rubycon substitutes (400LLE4.7MEFCT810X12.5 and 400LLE4R7MEFC10X12.5) are ROHS3 Compliant. The Nichicon ULD2G4R7MPD is also ROHS3 Compliant. However, the Nichicon part is REACH Affected, whereas the original and primary substitutes are REACH Unaffected.

Q: What is the advantage of the extended lifetime rating in substitute parts?

A: The Rubycon and Nichicon substitutes provide 15000 hours lifetime at 105°C, compared to 2000 hours for the original SEK4R7M400ST. This extended rating indicates improved thermal stability and longer operational life under continuous elevated temperature conditions. The substitute parts also provide higher ripple current capacity (61 mA at 120 Hz and 122 mA at 100 kHz versus 55 mA and 99 mA respectively).

Q: Can height dimension differences affect circuit performance?

A: No. Height dimension variations (14.00mm to 16.00mm) do not affect electrical performance. All parts maintain identical electrical characteristics: capacitance, voltage rating, tolerance, and ripple current handling. Reduced height in substitute parts provides additional PCB clearance without performance impact.

Q: Which substitute should be selected for new designs?

A: For new designs, select either Rubycon LLE series part (400LLE4.7MEFCT810X12.5 or 400LLE4R7MEFC10X12.5). Both maintain Active product status, extended lifetime ratings, and full compliance certifications. The Nichicon ULD2G4R7MPD should not be used for new designs due to its legacy product classification.