Key Points for New Energy Vehicle High-Voltage Harness Cable Selection: Voltage, Current, Shielding, and Temperature Rise
2026/09/18 42
New energy vehicle high-voltage harness cable selection must simultaneously meet four requirements: voltage rating matching the vehicle platform voltage, current capacity covering continuous and peak currents, shielding structure suppressing electromagnetic interference, and temperature rise control ensuring insulation life. Missing any one may lead to vehicle-level EMC test failure or long-term reliability risks.
Related Topics
Key Points for New Energy Vehicle High-Voltage Harness Selection
Cable Requirements for 800V Platforms
How to Solve High-Voltage Harness EMC Issues
Temperature Rise Standards for Automotive Cables
High-voltage harnesses are the main artery of power transmission in new energy vehicles. As vehicle voltage platforms and power density increase, cable selection is shifting from "functional" to "reliable + compliant".
Factor 1: Voltage Rating
The cable's rated voltage must be higher than the system's maximum operating voltage and cover transient overvoltages (such as regenerative braking and load transients).
High-voltage platforms impose stricter requirements on insulation thickness and dielectric strength of insulation materials.
During selection, request dielectric test reports from suppliers rather than relying only on nominal values.
Factor 2: Current Capacity and Temperature Rise
Continuous current determines the conductor cross-section, while peak current determines short-term overload capability.
Derating is required for bundled installation, enclosed chassis areas, and zones near heat sources.
Excessive temperature rise directly shortens insulation life and is the primary cause of harness failure.
Factor 3: Shielding and EMC
High-voltage high-current circuits are strong interference sources that can affect BMS sampling, communication buses, and in-vehicle electronic devices.
Shielding solutions include braided shielding, foil shielding, and composite shielding, and must be paired with reliable 360° grounding.
Improper grounding of the shielding layer will significantly degrade shielding effectiveness.
Factor 4: Mechanical and Environmental
Vibration zones (motor, chassis) require highly flexible and fatigue-resistant structures.
High-temperature zones (engine compartment, battery pack) require high temperature ratings.
Wiring in tight spaces requires a small bending radius, in which case extra-flexible structured cables should be considered.
Typical Application Locations
Battery packs, motors, electronic controls (the "three electrics"), on-board chargers (OBC), DC-DC converters, high-voltage distribution boxes (PDU), charging piles and charging guns, electric air-conditioning compressors, and PTC heaters.
Fahua Cable EV / EVP Series
Offering high-voltage resistance, high/low-temperature resistance, EMI immunity, and high flexibility, compliant with relevant automotive cable standards, and designed for the harsh high-temperature, high-interference environments of new energy vehicles. Dielectric, temperature rise, shielding effectiveness, and bending fatigue testing support are available.
Conclusion
High-voltage harness selection is a multi-constraint balancing process. It is recommended to conduct joint reviews with cable suppliers at the design stage to avoid later rework. Consultation: 13355985769.
