Custom dynamic contact resistance tester Factory: What Buyers Should Check Before Ordering
Measured Performance in Real Use
The build method decides how repeatable the milliohm reading stays after thousands of cycles. A welded bus‑bar path keeps the contact resistance drift below 0.5 % over 10 k operations, while a screw‑terminal version can drift 1.2 % under the same load.
| Test Environment | Common Drift Issue | Control Spec |
|---|---|---|
| High‑current production line, 25 °C ±5 °C | Thermal EMF offset causing 0.8 % reading shift | Four‑wire Kelvin sensing with on‑board temperature compensation ±0.1 °C |
| Vibration‑heavy test bench, 30 Hz sweep | Connector loosening leads to intermittent spikes | Locking‑type BNC with 30 N retention force |
| Humid chamber, 85 % RH | Corrosion on sense leads adds 2 mΩ | Gold‑plated contacts, IP65 sealed housing |
Matching the Product to the Buyer's Need
Consistency is set at the forming stage of the test fixture. A buyer running a 5 k‑unit batch per shift needs a tester that holds calibration across shift changes without manual re‑zero.
- Select a model with automatic zero‑offset correction if the line runs >8 h continuous.
- Choose the 4‑wire Kelvin probe when the device under test has ≤10 mΩ resistance.
- Specify the 24 V DC supply option for sites that lack 110 V AC.
Process choice shows up later as warranty claim frequency; the automatic correction variant reduces claims by roughly 30 % in field data.
OEM and ODM Programme Structure
Two programme tracks exist. OEM uses the standard firmware and enclosure, only branding changes. ODM opens the firmware API and allows custom measurement ranges.
OEM vs ODM Comparison
OEM Track
- Lead time 4 weeks after artwork approval.
- MOQ 50 units.
- No firmware change, lower NRE.
ODM Track
- Lead time 8‑10 weeks including firmware validation.
- MOQ 100 units.
- Custom range up to 5 A, 0.1 mΩ resolution.
What Gets Checked Before Shipment
Every unit passes a 5‑point functional test: Kelvin accuracy ±0.2 % at 1 A, temperature compensation verification, connector retention pull test, firmware checksum, and visual inspection for label adhesion.
Inspection records are logged per serial number and shipped with the packing list. A failed unit triggers a root‑cause report within 48 h.
Volume Planning and Lead Time
Standard stock covers 200 units per month. For orders above 500 units the line adds a second shift, cutting per‑unit lead time from 4 weeks to 2.5 weeks.
- Forecast 3 months ahead to lock capacity.
- Buffer stock of 10 % recommended for seasonal peaks.
Care, Storage and Service Life
Store in the original anti‑static bag at 15‑30 °C, 40‑60 % RH. Re‑calibrate annually or after 20 k measurements, whichever comes first. The gold‑plated contacts survive 500 mating cycles without measurable resistance increase.
Questions Buyers Ask Before Ordering
What is the typical calibration interval?
Annual calibration is standard; high‑throughput lines often schedule every 6 months.
Can the firmware be updated in the field?
Yes, via USB‑DFU; ODM units expose a secure bootloader for custom scripts.
What packaging options exist for export?
Individual ESD‑safe cartons, master cartons of 10, palletised with stretch wrap and shock indicators.
Is there a warranty on the measurement accuracy?
Two‑year accuracy warranty covering drift beyond 0.3 % when calibrated per schedule.
