How do I select the right connector for a wire harness?

Professional connector selection requires comprehensive evaluation of wire gauge matching, working current with derating, ambient environment (temperature, moisture, dust), IP protection grade, assembly method and anti‑mismatch requirements. This tool generates standardized engineering selection suggestions based on industry rules.

What is multi‑pin connector current derating?

When multiple connector pins carry current simultaneously, internal heat accumulation reduces the allowable current rating. More active circuits mean higher temperature rise and lower effective current capacity. Derating values vary by connector structure, terminal spacing and housing material. Always verify with manufacturer datasheets.

What is the difference between sealed and unsealed automotive connectors?

Unsealed connectors rely only on housing geometry, suitable for dry interior environments with low moisture and dust. Sealed connectors incorporate rubber wire seals and interface gaskets, providing dust‑proof and water‑splash resistance for under‑hood and outdoor exposed applications. Sealed assemblies require matching seals and plugs.

What IP rating is required for automotive under‑hood connectors?

Automotive under‑hood applications generally require sealed environmental protection, but the appropriate IP rating depends on actual water, dust, temperature, chemical and exposure conditions. Always cross‑check against connector manufacturer specifications.

Why must terminals strictly match wire AWG range?

Mismatched terminal and wire gauge will cause insufficient crimp pull force, poor electrical conductivity, excessive contact resistance and heat generation. Automotive harness USCAR‑21 standards clearly define crimp height, compression rate and tensile requirements for matched wire and terminal specifications.

Connector Selector

Pick the right connector for your application in seconds - voltage, current, pins, IP rating, keying, locking and termination in one place.

Your Requirements

Wire & Circuit

Wire gauge (AWG)

Wire construction

Cable outer diameter (mm)

Total pins

Active (powered) pins

Electrical

Operating voltage (V)

Current per circuit (A)

Temperature

Min. operating temperature (°C)

Max. operating temperature (°C)

Environment

Application scenario

Ingress protection (IP)

Mechanical

Termination type

Connection type

Connector gender

Locking mechanism

Keying (misplug prevention)

Recommendation report

Recommended connector family

Calculating...

Specification summary

Electrical check

Environment & temperature review

Risk assessment

DFM tips

Reference standards

Frequently asked questions

By convention, the female (socket) side stays on the power or control side and the male (pin) side on the load side, so exposed live pins are avoided. For custom harnesses, Kaweei builds either orientation to match your drawing.

Keying ensures a connector can only mate in the correct orientation and with its counterpart. In multi-branch harnesses it prevents misplugging circuits that use the same housing.

IP65 handles rain and water jets, IP67 survives temporary immersion, and IP69K is required for high-pressure, high-temperature washdown such as agricultural and commercial vehicles.

Crimp is the industry standard: vibration-resistant, consistent and automation-friendly. Solder can wick into strands and create rigid points, so use it only where the connector specification allows.

Yes. We process TE, Molex, JST, Amphenol and equivalent connectors, with 100% electrical testing on every assembly. Send your pinout for a free quote within 24 hours.

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Ampacity Calculator

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