EPCOS TDK B43570 Series Aluminum Electrolytic Capacitors — B43570-S4338-Q3

Technical Dossier

Product Details And Specifications

EPCOS TDK B43570 Series: Comprehensive Module Range and Technical Overview

The EPCOS TDK B43570 series represents a family of screw-terminal aluminum electrolytic capacitors engineered for high-reliability industrial power electronics. These components are deployed across heavy industrial sectors including chemical processing plants, oil refineries, nuclear facility auxiliary power systems, wind turbine converters, industrial UPS installations, and variable-frequency drive (VFD) cabinets. The B43570 series is characterized by its snap-in and screw-terminal mounting format, high capacitance density, and rated voltage range spanning 350 V to 500 V DC, making it a standard specification component in DC bus filtering and energy storage stages of industrial inverters and rectifiers. The series is manufactured to IEC 60384-4 standards and carries a rated lifetime of 2,000 to 5,000 hours at maximum category temperature (85°C), with extended life achievable under derated operating conditions. Global installed base spans European, North American, and Asian industrial automation infrastructure, with the B43570 family remaining a reference design in legacy power conversion equipment manufactured between 1995 and the present.

The Evolution of B43570 Architecture

The B43570 series was introduced by EPCOS AG (formerly Siemens Matsushita Components) as part of a rationalization of industrial-grade screw-terminal capacitor families in the mid-1990s. Early production variants used standard aluminum foil with paper separator technology and were rated for 85°C category temperature. Subsequent design revisions introduced improved electrolyte formulations that extended operational lifetime under high-ripple-current conditions, directly addressing field failures observed in high-switching-frequency IGBT inverter applications. The transition from EPCOS AG to TDK Corporation ownership (completed 2017) did not alter the core part numbering schema; B43570 part numbers remained valid and cross-compatible across production generations. The series coexists with the B43560 (lower voltage, snap-in) and B43580 (higher capacitance, larger case) families within the TDK EPCOS screw-terminal portfolio. For new designs, TDK recommends the B43706 and B43720 series as modern successors with improved ripple current ratings and longer rated lifetimes (up to 7,000 hours at 85°C). However, the B43570 remains in active production for aftermarket and MRO supply chains, and DriveKNMS maintains stock of both current-production and legacy-date-code units for direct replacement applications.

B43570 Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly stocked configurations within the B43570 series. Each entry reflects a distinct capacitance/voltage/case-size combination used in industrial power electronics:

• B43570-S4338-Q3: 3,300 µF / 400 V, screw-terminal, Ø35×50 mm, DC bus filter capacitor for medium-power inverters
• B43570-S4228-Q1: 2,200 µF / 400 V, screw-terminal, Ø30×40 mm, standard DC link stage for VFD drives up to 15 kW
• B43570-S5688-M1: 6,800 µF / 450 V, screw-terminal, Ø51×80 mm, high-capacitance bus filter for large UPS systems
• B43570-S9478-M1: 4,700 µF / 500 V, screw-terminal, Ø51×80 mm, 500 V DC bus energy storage in heavy industrial converters
• B43570-S6338-Q1: 3,300 µF / 450 V, screw-terminal, Ø40×60 mm, mid-range inverter DC link filtering
• B43570-S4688-Q1: 6,800 µF / 400 V, screw-terminal, Ø51×60 mm, bulk energy storage in regenerative drive systems
• B43570-S5478-M1: 4,700 µF / 450 V, screw-terminal, Ø51×65 mm, ripple current rated for high-frequency switching applications
• B43570-S9228-M1: 2,200 µF / 500 V, screw-terminal, Ø35×50 mm, compact 500 V DC link for space-constrained enclosures
• B43570-S6228-Q1: 2,200 µF / 450 V, screw-terminal, Ø30×45 mm, replacement unit for legacy Siemens SIMOVERT drives
• B43570-S4478-Q1: 4,700 µF / 400 V, screw-terminal, Ø40×60 mm, standard bulk capacitance for 400 V three-phase rectifier outputs
• B43570-S5228-M1: 2,200 µF / 450 V, screw-terminal, Ø35×55 mm, auxiliary power supply filtering in industrial control panels
• B43570-S6478-Q1: 4,700 µF / 450 V, screw-terminal, Ø40×65 mm, DC bus capacitor for wind turbine pitch control converters
• B43570-S9338-M1: 3,300 µF / 500 V, screw-terminal, Ø40×65 mm, 500 V rated unit for offshore and marine power systems
• B43570-S4568-Q3: 5,600 µF / 400 V, screw-terminal, Ø51×55 mm, high-capacitance 400 V unit for active front-end rectifiers
• B43570-S6568-Q1: 5,600 µF / 450 V, screw-terminal, Ø51×60 mm, long-life DC bus capacitor for continuous-duty industrial drives

Sourcing Hard-to-Find & Obsolete B43570 Parts

The B43570 series, while still in active TDK production for core configurations, includes numerous date-code-specific and regional-market variants that have been discontinued or are subject to extended lead times through standard distribution channels. DriveKNMS maintains a dedicated MRO inventory of B43570 units sourced from verified industrial surplus, OEM overstock, and authorized distributor closeouts. All units are stored in climate-controlled conditions to preserve electrolyte integrity and prevent capacitance drift associated with improper storage. For plant maintenance teams operating legacy Siemens SIMOVERT, ABB ACS, or Danfoss VLT drive platforms where the B43570 is a specified replacement component, DriveKNMS provides direct cross-reference matching against OEM bill-of-materials documentation. Requests for specific date codes, lot traceability, or matched-set quantities for parallel capacitor bank replacements are handled on a case-by-case basis. Minimum order quantities are flexible for MRO customers. Lead time for in-stock units is typically 3–7 business days for international shipment.

Quality Control for the B43570 Range

Each B43570 unit processed by DriveKNMS undergoes a structured incoming inspection protocol prior to dispatch. Capacitance measurement is performed at 120 Hz using a calibrated LCR meter, with acceptance criteria set to ±20% of rated capacitance per IEC 60384-4. Equivalent series resistance (ESR) is measured and compared against published TDK datasheet values for the specific part number and date code. Leakage current is tested at rated DC voltage (400 V, 450 V, or 500 V as applicable) with a 5-minute soak period; units exceeding the IEC-specified leakage threshold are rejected. Physical inspection covers terminal integrity, case deformation, vent condition, and label legibility. Units sourced from industrial surplus undergo additional dielectric absorption testing to assess electrolyte condition. Test records are retained per shipment lot and are available to customers upon request for critical maintenance applications.