"Charging Guns in Every Home: Do You Know the Industry Specs?"
As a core component of the EV charging station, the charging gun directly reflects the overall quality of the station. If the specifications, material quality, and manufacturing processes of the charging gun cable assembly fail to meet the required standards, it will pose unpredictable safety hazards and cause irreversible damage to your vehicle's battery. Since Zhongyao Automation frequently customizes automated production lines for charging gun cable assemblies and connectors for major new energy vehicle manufacturers, we would like to share some professional insights into the manufacturing processes and key considerations regarding charging guns.
As a critical safety component in the new energy vehicle charging system, the specifications and manufacturing processes of charging gun cable assemblies are strictly regulated by national and international standards.
Core Specification Standards
The specifications for charging gun cable assemblies primarily adhere to the following national standards.
Cable Body Standard: GB/T 33594-2017 This is currently the most core domestic standard dedicated to cables for electric vehicles.
Voltage Rating: Applicable to cables with a rated AC voltage not exceeding 0.6/1kV and a rated DC voltage not exceeding 1.5kV. The latest connection device standards have upgraded the DC voltage specification to 1500V.
Conductor Specifications: Conductors must use oxygen-free copper with a purity of ≥99.9%. Common cross-sectional area specifications include 0.5, 1, 1.5, 2.5, 4, 6, 10, 16, 25, 35, 50, and 70 mm².
Low Power (e.g., 7kW): Typically uses 3×6mm² or 3×10mm² cables.
High Power (e.g., 60kW and above): Typically uses cables with cross-sectional areas of 35mm², 50mm², or even larger, often incorporating liquid cooling technology for heat dissipation.
Material Characteristics: Insulation and sheath materials must possess excellent oil resistance, ozone resistance, weather resistance (UV protection), and flame retardancy (typically required to meet VW-1 or FT1 levels).
Flexibility Requirements: Since charging gun cables require frequent bending and dragging, the standard mandates that they must pass rigorous flexing life tests (typically requiring tens of thousands of bending cycles without breakage).
Connection System and Interface Standard: GB/T 20234 Series This series of standards specifies the physical dimensions, electrical parameters, and general requirements for charging interfaces, ensuring compatibility between charging equipment and vehicles.
GB/T 20234.1: General requirements.
GB/T 20234.2: AC charging interface.
GB/T 20234.3: DC charging interface.
Other Related Standards
Energy Industry Standards: Such as NB/T 33001 and NB/T 33002, which specify connection specifications and temperature rise limits for charging stations and their internal cable assemblies.
International Standards: Exports or specific markets may also need to comply with IEC 62893 (International), EN 50620 (Europe), UL 2263 (USA), and other standards.
Manufacturing Process Standards
The manufacturing process for charging gun cable assemblies is a meticulous procedure designed to ensure electrical performance, mechanical strength, and environmental adaptability. The main processes include.
Design and Material Selection Based on charging power (AC slow charging/DC fast charging) and current magnitude, select appropriate cable specifications (cross-sectional area, voltage rating) and connector models. Conductors typically use oxygen-free copper or tin-plated copper, while sheath materials are selected from wear-resistant, high/low temperature resistant TPE/TPU, etc.
Cable Pre-processing
Cutting: Precisely cut cables to the length specified in the drawings, with tolerances typically controlled within ±1mm.
Stripping: Use laser or mechanical methods to strip the outer jacket and insulation, exposing the conductor to the specified length, while avoiding damage to the copper strands during the process.
Shielding Treatment: For cables with shielding layers, the braided shield must be grounded or fitted with metal sleeving to reduce electromagnetic interference.
Terminal Crimping Use professional crimping equipment to tightly crimp terminals onto the wire cores. Crimping quality is critical and must be inspected through methods like cross-sectional analysis to ensure airtightness and uniformity, guaranteeing that crimping pull force meets standards (e.g., ≥50N).
Injection Molding and Assembly
Secondary Injection Molding: Inject sealing compound (such as silicone) at the connector interface to achieve high levels of water and dust resistance, such as IP67/IP68.
Cable Assembly Fixing: Use cable ties, heat shrink tubing, or rubber sleeves to layer and secure the internal cable assembly, preventing internal friction and loosening.
Testing and Certification Finished products must pass a series of rigorous tests before leaving the factory to ensure safety and reliability.