cable assembly standards

I. Four Major Series of Standards for Low-Voltage Automotive Wires

• National Standard Cables (GB/T 8139)
• Reference Standard: GB/T 8139 is a Chinese national standard that covers the design, manufacturing, and testing specifications of low-voltage automotive wires.

Characteristics:

Weather Resistance:

• Given China's vast territory and diverse climates, national standard cables have relatively strict requirements regarding high-temperature resistance, low-temperature resistance, and resistance to damp heat. Especially in the frigid north and humid and hot south, the cables need to possess good anti-aging and ultraviolet resistance properties.

Materials:

• National standard cables mostly use materials such as polyvinyl chloride (PVC) and cross-linked polyethylene (XLPE), which exhibit excellent performance in terms of chemical corrosion resistance, abrasion resistance, and insulation properties.

Application Range:

• National standard cables are widely used in domestically produced automobiles, covering various needs from economy vehicles to high-end models.
•  Japanese Standard Cables (JASO D608, D609, D611)

 Reference Standard:

• The D608, D609, and D611 standards of JASO (Japanese Automotive Standards Organization).

Characteristics: 

Flexibility:

• Japanese standard cables are usually required to have better flexibility to meet the wiring requirements of compact vehicles, especially for wiring in the narrow spaces inside the vehicle.

Heat Resistance:

• Due to the relatively high summer temperatures in Japan, Japanese standard cables generally have higher requirements for heat resistance, with a typical operating temperature range of -40°C to 125°C.

Lightweight:

• To improve fuel efficiency, Japanese standard cables often use lighter materials, such as special thermoplastic elastomers (TPE), to reduce the vehicle's weight. 

Environmental Protection:

• Japan has strict environmental protection requirements, and Japanese standard cables place more emphasis on environmental protection and recyclability in material selection, reducing the use of harmful substances such as lead and halogens.
• German Standard Cables (ISO 6722)

 Reference Standard:

• ISO 6722 is the standard for automotive wires issued by the International Organization for Standardization and is widely adopted in Europe, especially in Germany.

Characteristics:

High-Temperature Performance:

• German standard cables have strict requirements for high-temperature resistance and antioxidant properties, with a typical operating temperature range of -40°C to 150°C, suitable for applications with high-performance engines and in harsh environments.

Mechanical Strength:

• The wires specified by the ISO 6722 standard need to have relatively high mechanical strength to prevent wear and breakage caused by vibration and friction during the long-term use of the vehicle.

Flame Retardancy:

• German standard cables are required to meet strict flame retardancy requirements to ensure that they do not accelerate the spread of fire in the event of a fire.

Long-Term Reliability:

• The German automotive industry is renowned for its precision manufacturing, so German standard cables have extremely high standards in terms of durability and stability, suitable for highly demanding automotive electronic systems.
•  American Standard Cables (SAE J1128, SAE J1678, US-CAR-21)

Reference Standard:

• The J1128 and J1678 standards of SAE (Society of Automotive Engineers), as well as the US-CAR-21 standard.

Characteristics:

Diversity:

• American standard cables cover a wide range of applications from economy to high-performance models, and the applicable temperature range and electrical performance requirements vary depending on the vehicle model, with a relatively high degree of flexibility.

Resistance to Extreme Environments:

• Due to the diverse geographical and climatic conditions in the United States, American standard cables need to maintain good performance in extreme temperature, humidity, and chemical corrosion environments. Their typical operating temperature range is -40°C to 105°C.

Resistance to Mechanical Damage:

• American standard cables often use thicker sheath materials and stronger anti-tension designs to cope with mechanical damage in extreme environments, such as those commonly encountered in off-road vehicles or commercial vehicles.

Standard Flexibility:

• American standards are usually more flexible, allowing manufacturers to adjust the design of the cables according to different vehicle models and usage environments, thus having higher market adaptability.

II. Differences between Different Standards

Application Regions and Markets

National Standard:

• Mainly used in the Chinese market, adapting to the climatic and environmental characteristics of China.

Japanese Standard:

• Applied in Japan and other Asian markets, with the design taking into account compact cars and high-humidity environments.

German Standard:

• Widely used in the European market, especially for German-brand vehicles, suitable for high-demand, high-precision automotive systems.

American Standard:

• Widely used in the North American market, emphasizing the diversity of cables and their adaptability to extreme conditions.

 Performance Requirements

Temperature Resistance Range:

• Different standards have different requirements for the temperature resistance of wires. German standards generally require higher temperature tolerance, while American standards pay more attention to performance under extreme low and high temperature conditions.

Mechanical Properties:

• German and American standards have higher requirements for resistance to mechanical damage and tensile strength, while Japanese standards place more emphasis on the flexibility and lightweight nature of the cables.

 Testing Methods

National Standard:

• Usually includes tests such as high-temperature aging, low-temperature bending, oil resistance, and acid-base resistance, with relatively comprehensive testing methods. 

Japanese Standard:

• Has unique requirements in testing flexibility and durability, such as testing under a smaller bending radius.

German Standard:

• Emphasizes aging tests and flame retardancy tests in high-temperature environments, with more stringent testing methods.

American Standard:

• Has a wide range of testing contents, especially durability and mechanical damage tests in extreme environments.

Applicable Vehicle Models

National Standard:

• Applicable to various domestic vehicle models, from passenger vehicles to commercial vehicles. 

Japanese Standard:

• Mainly applied to compact vehicles and small and medium-sized passenger vehicles of Japanese brands.

German Standard:

• Widely applied to high-end German brands such as BMW, Mercedes-Benz, and Audi, requiring precision and high reliability.

American Standard:

• Applicable to American-brand vehicles, especially large SUVs, trucks, and off-road vehicles, adapting to various complex terrains and climatic conditions.

These standards not only reflect the characteristics of the automotive industries in various countries but also profoundly influence the product design and production processes in their respective markets.

Selecting the appropriate cable standard is crucial for ensuring the performance, safety, and durability of vehicles.