Exploring the Dual World of Automotive High-Voltage and Low-Voltage Connectors
Automotive connectors are categorized as low-voltage and high-voltage connectors based on their operating voltage. Low-voltage connectors typically operate at 12V, 24V, or 48V. High-voltage connectors operate at voltages ranging from 60V to 800V, or even higher. High-voltage and low-voltage connectors differ primarily in appearance, structure, withstand voltage, protection requirements, EMC compatibility, and flame retardancy ratings.
Appearance
The main differences between high-voltage and low-voltage automotive connectors are color and size. Low-voltage connectors are primarily black, while high-voltage connectors are orange. Because high-voltage connectors carry high voltage and current, they are typically larger than low-voltage connectors.
Structure
High-voltage connectors are more complex and sophisticated than low-voltage connectors. Compared to low-voltage connectors, they primarily feature additional inner and outer shield rings and a high-voltage interlock. The low-voltage connector structure is shown in the figure below. It generally consists of a tie rod, sealing ring, housing, and TPA. The structure of the high-voltage connector is generally composed of terminals, insulators, plastic shells, shielding rings, seals, covers, etc.
Compared with low-voltage connectors, high-voltage connectors have an additional inner and outer shielding ring. After the high-voltage connector is assembled, the shielding ring will contact the shielding layer on the connector shell, and the high-voltage wire shielding layer will eventually be grounded, thus achieving 360° shielding protection for the high-voltage wire. In addition, most high-voltage connectors also include high-voltage interlocking terminals.
Withstand Voltage
A connector’s withstand voltage rating is primarily determined by factors such as the insulation material, creepage distance, and air humidity. Common connector materials include PBT, PA66, PA6T, and PA9T.
1) Low-voltage connectors are primarily used in ECUs and sensors, and are suitable for environments with voltages less than 30VAC/60VDC.
2) High-voltage connectors are primarily used to connect high-voltage equipment such as battery packs, PDUs, motors, air conditioning compressors, and heaters. Currently, the rated voltage of high-voltage connectors is around 1000VDC.
Protection Requirements
Automotive connectors can be categorized as sealed or unsealed depending on whether or not they require sealing. Low-voltage connectors have different sealing requirements depending on where they are used. Wet-area connectors generally have sealing requirements, while dry-area connectors do not. Only S3 low-voltage connectors meet the IP6K9K sealing rating.
EMC Compatibility
Low-voltage connectors are primarily used in voltage environments below 30VAC (60VDC). Electromagnetic interference (EMI) generated in these environments is limited, and wiring harnesses are typically shielded by twisting or wrapping with aluminum foil.
High-voltage connectors are primarily used to connect wires and high-voltage equipment. Currents flowing through these wires and equipment can reach hundreds of amperes, and the resulting EMI is significant, requiring 360° shielding. Currently, high-voltage wires typically have a shield layer composed of braided wire and aluminum foil. Accordingly, high-voltage connectors are designed with an integrated shield layer.
Choosing an Automotive Wiring Harness Connectors Terminals Supplier: Insights into Manufacturer Differentiation
In the highly specialized and demanding automotive wiring harness terminal industry, supplier selection directly impacts product performance, reliability, and supply chain stability. While many suppliers offer “standard” products, Heju Precision stands out as a leading partner for popular vehicle models such as BMW, QX, and Geely. The core of Heju Precision’s success lies in a series of unique, internalized capabilities and commitments. These qualities permeate every aspect of its service, production, and quality systems, creating a competitive advantage that is difficult to replicate.
Heju Precision Stamping Automotive Connectors Terminals
Service: From Order Execution to Deeply Collaborative “Engineering Partner”
Heju Precision breaks away from the traditional “on-demand delivery” service model. Its core value lies in deep collaboration with customers’ R&D and production processes.
- Early Participation in Customer Design and Development
Heju’s application engineering team is accustomed to intervening in the early stages of customer product design. They go beyond simply accepting specification requirements and proactively propose design for manufacturability optimization solutions based on their in-depth understanding of material properties, stamping process boundaries, and connector matching trends. This approach effectively avoids multiple mold redesigns, project delays, and increased costs caused by design flaws, significantly improving the overall efficiency and success rate of customer projects. This “preemptive intervention, risk prevention” service philosophy is unmatched by traditional, build-to-print suppliers.
- Transparent Collaboration and Risk Early Warning
Heju emphasizes information openness and proactive management. Rather than waiting for customer inquiries, they establish a supply chain health monitoring mechanism to anticipate potential risks such as fluctuations in key raw materials and production capacity constraints, and proactively collaborate with customers to develop response strategies. This commitment to “taking customer challenges as our own responsibility” provides a solid foundation for the smooth operation of our customers’ supply chains.
Manufacturing: Core Capabilities of “Micron-Level Precision” and Vertical Integration
- Micron-Level Process Control
In precision components such as automotive electrical wire terminals, micron-level dimensional deviations directly impact electrical performance and connection reliability. Heju leverages its proprietary high-precision stamping dies technology. Combined with real-time equipment monitoring and process optimization, to achieve ultimate control over critical dimensions. This precise mastery of the “micron world” forms the foundation for its product consistency and high reliability.
- Vertical Integration Empowers Manufacturing Agility
Heju possesses the ability to independently design and manufacture progressive molds, eliminating dependence on external mold suppliers. If mold adjustments or optimizations are needed, the internal team can respond quickly, significantly shortening iteration cycles and accelerating time to market.
- Deep Integration of Materials and Processes
Heju not only specializes in stamping and forming parts, but also focuses on research in materials science and surface treatment processes. By systematically understanding the properties of copper alloys (such as elastic modulus and yield strength) and the coating process (uniformity and adhesion), we continuously carry out closed-loop verification of “materials-processes-performance” to ensure that each product fully meets the stringent requirements of customers in terms of electrical, mechanical, corrosion resistance and other properties.
Quality: A “Zero Defect” Philosophy Embedded in Our DNA and Customer-Oriented Continuous Improvement
At Heju, quality is more than just an inspection system; it’s a corporate culture and operational principle.
- Preventive Quality Management
Leveraging a comprehensive APQP (Advanced Product Quality Planning) process, Heju systematically identifies quality risks and develops control plans from the outset of each project. We implement Statistical Process Control (SPC) to integrate quality control throughout the entire manufacturing process, emphasizing “get it right the first time” and significantly reducing defect rates.
- Exceeding Standards in the Pursuit of “Zero Defects”
While the industry generally accepts AQL sampling inspection standards, Heju pushes the boundaries by setting process control targets (such as high Cpk values) far exceeding customer requirements. We achieve “Zero Defects” through full or frequent spot checks of critical dimensions and rigorous process stability monitoring. Choosing Heju Precision means more than just choosing a supplier. It means partnering with a long-term strategic engineering partner with deep expertise, unparalleled manufacturing capabilities, and a commitment to “Zero Defects.”