Our Commitment to Quality

How We Test Every Capacitor

Capacitor quality cannot be verified by visual inspection alone. A capacitor that looks perfect on the outside may have degraded electrolyte, internal open circuits, or out-of-specification electrical parameters. That's why Specap performs 100% electrical testing on every capacitor before it ships — not batch sampling, not spot checks, but every single unit.

Our testing process measures the three most critical electrical parameters that determine whether a capacitor will perform reliably in your application:

• Capacitance value — We verify that the actual capacitance falls within the manufacturer's specified tolerance band. A capacitor labeled 100µF ±20% must measure between 80µF and 120µF. For audio, precision timing, and filter applications, tighter tolerances (±5% or ±10%) are verified against the part's specification. Learn more in our capacitor sizing guide.
• ESR (Equivalent Series Resistance) — ESR measures the internal resistance of the capacitor at a specified frequency. High ESR indicates electrolyte degradation in aluminum electrolytic capacitors or internal connection problems. Even NOS (New Old Stock) capacitors can develop elevated ESR from prolonged storage. See our ESR reference guide for typical values by capacitor type.
• Leakage current — DC leakage current testing applies the rated voltage to the capacitor and measures the current that flows through the dielectric. Excessive leakage indicates dielectric damage, contamination, or age-related degradation. This test is particularly important for tantalum capacitors and aluminum electrolytic capacitors, where leakage current is a primary failure indicator.

Counterfeit Prevention in the Capacitor Supply Chain

Counterfeit electronic components are a serious and growing problem. The Defense Logistics Agency, NASA, and the SAE International have all documented incidents of counterfeit capacitors entering the supply chain — particularly for military and aerospace applications where MIL-PRF qualified parts carry premium pricing that incentivizes fraud.

Common counterfeit capacitor risks include:

• Relabeled commercial parts — Standard commercial-grade capacitors re-marked as military-grade (MIL-PRF) or higher-rated specifications
• Used parts sold as new — Capacitors salvaged from scrapped equipment, cleaned, and re-sold as new production
• Substandard manufacturing — Capacitors from unauthorized factories using inferior materials while copying legitimate manufacturer branding
• Expired or degraded stock — Old inventory with altered date codes to appear fresh, masking potential shelf life degradation

Specap mitigates these risks through our multi-layered authentication process: verified supply chain sourcing, visual and marking inspection, electrical parameter testing against manufacturer specifications, and documentation verification including lot codes, date codes, and certificates of conformance. Our adherence to AS6171 (Test Methods Standard for Counterfeit Electronic Parts) provides the framework for our counterfeit detection program.

Traceability and Documentation

For customers in aerospace, medical, and defense industries, component traceability isn't optional — it's a regulatory requirement. Specap maintains full traceability records including:

• Manufacturer name and country of origin
• Lot codes and date codes for every component
• Supplier chain documentation from authorized sources
• Certificates of conformance (CoC) upon request
• Electrical test data and inspection records
• GIDEP (Government-Industry Data Exchange Program) alert monitoring

This documentation supports AS9120 (aerospace distributor quality), FDA 21 CFR Part 820 (medical device quality), and DFARS compliance requirements. Whether you need a single capacitor for a prototype or thousands for a production run, we provide the same level of quality verification and documentation support.

Special Testing for Obsolete and NOS Capacitors

Obsolete and NOS capacitors require additional attention during quality verification. Aluminum electrolytic capacitors that have been stored for extended periods may need reforming — a controlled voltage application process that restores the oxide dielectric layer. Our technicians evaluate each lot of NOS electrolytic capacitors to determine if reforming is needed and perform the process when required before testing and shipping.

For film capacitors and ceramic capacitors, long-term storage generally does not degrade performance, but we still verify electrical parameters to confirm that storage conditions have not caused any measurable deterioration.

Storage Conditions & Handling

Proper storage is critical to capacitor longevity. Our facility maintains strict environmental controls to ensure every component ships in optimal condition:

• Temperature — Warehouse maintained between 15–35°C (59–95°F). Temperature excursions are logged and investigated.
• Humidity — Relative humidity kept below 60% with continuous monitoring. Moisture-sensitive components are stored in sealed moisture barrier bags with desiccant per IPC/JEDEC J-STD-033.
• ESD Protection — All handling follows ANSI/ESD S20.20 standards. ESD-safe packaging, grounded workstations, and personnel grounding are mandatory throughout our facility.
• FIFO Rotation — First In, First Out inventory management ensures older stock ships before newer arrivals, minimizing shelf-age-related degradation.
• Electrolytic Reforming — Aluminum electrolytic capacitors stored beyond 2 years undergo a controlled voltage application process that gradually restores the aluminum oxide dielectric layer. This prevents excessive leakage current and potential failure on first power-up. Learn more in our reforming guide.

Date Code Standards & Shelf Life

Understanding date codes is essential for quality assurance and inventory management. All capacitors in our inventory have verified date codes recorded in our tracking system.

• Standard Format (YYWW) — Most manufacturers use a 4-digit code where the first two digits represent the year and the last two represent the week. For example, 2348 means week 48 of 2023.
• Manufacturer Variations — Some manufacturers use proprietary formats: Nichicon uses a letter-number system, Cornell Dubilier includes lot traceability codes, and some military parts use Julian date codes. Our team is trained in all major formats.

Maximum recommended shelf life varies significantly by capacitor type:

• Aluminum Electrolytic — 2–5 years without reforming. The liquid electrolyte slowly degrades the oxide layer over time. Units stored beyond this window require reforming before use. Read our shelf life guide for details.
• Film Capacitors — 10+ years. Film dielectrics are inherently stable and show minimal degradation in storage under proper conditions.
• Ceramic Capacitors — 10+ years. Ceramic dielectrics are inert and chemically stable. The primary storage concern is mechanical damage from handling.
• Tantalum Capacitors — 5–7 years. While the tantalum pentoxide dielectric is stable, the manganese dioxide cathode can slowly degrade, increasing leakage current.
• Motor Capacitors — 5–10 years depending on type. Oil-filled motor capacitors have longer shelf life than dry-film types.