Wholesale capacitance dissipation factor tester Supplier: Specification, Ordering and Quality Notes

Scope of Supply and Physical Form

Every unit ships with a calibrated HV lead set (3 m), ground return cable, USB flash with test report templates, and a traceable calibration certificate referencing NMI-held standards. The standard carton is a double-wall corrugated box with custom-cut PE foam — tested to ISTA 2A for air freight. Palletised orders use heat-treated ISPM-15 crates with desiccant packs and shock indicators.

Optional accessories that change the measurement envelope: three-terminal guard box for low-loss dielectric samples, temperature correction probe (Pt100, ±0.1 °C), and a 200:1 capacitive voltage divider for on-site transformer bushing tests up to 20 kV. Each accessory carries its own calibration sticker and serialised test record.

Measured Performance in Real Use

Field data from three utility labs running 12 kV units continuously for 18 months shows tan δ repeatability holding within ±0.00008 at 10 kV, 100 pF — half the published spec. The limiting factor isn't the analog front end; it's connector oxidation on the HV output after 400+ mate cycles. Gold-plated N-type connectors (option code -G) extend that interval to 1,200 cycles.

Noise floor at the substation matters more than bench specs. With the standard Wi-Fi module active, common-mode rejection drops 12 dB above 30 MHz. The fiber-optic Ethernet option (-FO) restores full CMRR and eliminates ground loops when the tester shares a circuit with switchgear. Buyers who skip -FO to save $420 per unit typically retrofit within six months after a failed audit.

Bench-Top Configuration

Fixed lab position, controlled temperature, dedicated HV circuit. Standard aluminum enclosure sufficient. Calibration interval: 12 months. Weight and footprint stable — no drift in divider ratio observed across 50 thermal cycles (-10 °C to +40 °C).

Best for: incoming QC on capacitor batches, dielectric material R&D, standards lab reference.

Field-Deployable Configuration

Transit case, shock mounts, -FO fiber link, -G gold connectors, external battery pack (8 hr). Divider ratio verified after each transit — 0.02% max shift. Calibration interval: 6 months or 200 HV hours, whichever comes first.

Best for: transformer bushing diagnostics, cable tan δ surveys, substation commissioning crews.

OEM and ODM Programme Structure

Private-label buyers receive a frozen BOM at first article approval. The firmware build, HV divider resistor network, and ADC part number are locked to that revision. Any component substitution triggers a deviation notice and a new first-article test report — no silent changes. This is the single control that prevents the lot-to-lot consistency complaints referenced earlier.

ODM projects follow a gated review: requirements freeze → schematic review → prototype (3 units) → environmental stress screening (-40 °C to +70 °C, 95% RH) → pilot run (25 units) → production release. Typical timeline: 16 weeks from requirements to pilot, 8 weeks from pilot to first shipment. Tooling costs for custom enclosures or specialized HV electrodes are amortised over the first 100 units or paid upfront at buyer's choice.

Branding options: silk-screen logo on front panel, custom boot splash screen, localized UI language packs (EN, DE, FR, ES, CN, JP, KR standard; others on request). Regulatory marks (CE, UKCA, KC, RCM) are applied per destination market; the technical file stays with the manufacturer unless a full design transfer is negotiated.

Inspection Items and Test Methods

Every production unit passes a 14-point final test before the calibration certificate is issued:

• HV output waveform purity — THD < 1.5% at 12 kV into 100 pF
• Voltage amplitude accuracy — ±1% of setting, verified at 5 points per range
• Tan δ accuracy — checked against 3 certified standard capacitors (100 pF, 1 nF, 100 nF)
• Capacitance linearity — 10 points across each decade, max deviation 0.2% rdg
• Noise floor — < 0.00002 tan δ at 10 kV, 100 pF, 10 s integration
• Interlock continuity — all safety loops tested at 500 V DC insulation resistance
• Thermal stability — 4 hr soak at 40 °C, re-measure reference capacitor
• Communication integrity — 10,000 packet stress test on each enabled interface

Incoming QC on critical sub-assemblies: HV transformer (inductance, leakage, partial discharge < 5 pC at 1.2× rated), divider resistor network (TCR < 10 ppm/°C, ratio match ±0.01%), ADC module (ENOB ≥ 18 bits at 1 kS/s). Each sub-assembly carries a lot code traceable to the component reel. We retain traceability records for 7 years minimum.

Capacity, Tooling and Scheduling

Standard model: 40 units/month from standing inventory of long-lead parts (HV transformers, custom ADC boards). Peak capacity 60 units/month with 6-week notice. OEM/ODM allocations are carved out of the peak band — they do not displace standard stock.

Lead times ex-works: standard configuration 3 weeks ARO; -G/-FO options add 1 week; custom voltage range or enclosure adds 4–6 weeks. Blanket orders with monthly call-offs lock pricing for 12 months and guarantee slot reservation. First-article inspection at our facility or buyer's site — buyer's choice, travel costs on buyer for overseas visits.

Spare parts inventory: HV output modules, divider boards, display assemblies, and connector kits held for 5 years post-last-ship. Firmware updates delivered via encrypted OTA or USB — no license fees, no subscription. Legacy units (discontinued > 7 years) supported on best-effort basis with 30-day quote turnaround.

Setup, Use and Replacement Parts

Initial commissioning: unpack, inspect shock indicators, connect ground stud to verified earth (< 1 Ω), run self-test (15 min), verify reference capacitor reading within ±0.00005 of certificate value. No warm-up required beyond 5 min for thermal equilibrium. The HV output is interlocked — the tester will not energize unless the ground return path continuity is confirmed.

Routine maintenance: clean HV terminal insulators with isopropyl alcohol monthly in dusty environments. Inspect connector pins for pitting every 200 HV hours — replace at first sign of erosion (part number HV-CONN-KIT, $85). Firmware updates quarterly; changelog includes measurement algorithm fixes, not just UI tweaks. Calibration recall: 12 months bench, 6 months field — automated email reminder sent to registered contacts.

Consumables with genuine service life limits: desiccant cartridge in HV tank (24 months), cooling fan filter (18 months), internal backup battery for RTC (5 years). All user-replaceable with a Torx T10 driver — no soldering, no calibration shift after replacement. The service manual includes torque values for every HV connection (1.2 N·m for N-type, 0.8 N·m for BNC).