The automotive industry is one of the world's most innovative realms, constantly pushing the bounds of what is possible, cost-effective, safe, scalable, attractive, and reliable. And as the automotive industry continues to evolve, new technologies such as autonomous driving, smart PCM/ECM/ECUs, highly intelligent electric battery systems, and smart-charging grids are emerging and evolving each year.
The growth of these technologies has led to a massive increase in the total number of low- and high-voltage interconnects that are used in the automotive industry. Naturally, safety and reliability standards are paramount to the short- and long-term success of these emerging technologies but these standards can result in large challenges for automakers.
This article presents common automotive electrical connector standards, including high-voltage automotive power connectors, and the design challenges associated with complex Electric Vehicle (EV) connectors that are commonly used in the automotive EV industry. Be sure to also check out Arrow.com’s selection of electrical connector types.
Automotive Electrical Connector Standards
Automotive connectors can range from something as small as low-voltage communication wire-to-board interconnects to high-voltage EV-charging connectors capable of safely conducting hundreds of volts in the pouring rain. The adherence to different standards is often required based on the geographic operating location of the vehicle, as well as the technology utilized and its location within the automobile.
For example, low-voltage signal connectors residing inside the cabin of a vehicle may not require the same waterproof rating (IP rating) as signal connectors located in the engine compartment.
Common automotive connector standards vary around the globe, as there is not a unified global automotive standardization organization, but the most commonly referenced automotive standard-setting organizations are:
- • ISO - International Organization for Standardization
- • IEC - International Electrotechnical Commission
- • SAE - Society of Automotive Engineers
- • GB - Guobiao Standards (Peoples Republic of China)
These organizations provide regulatory and standard-setting efforts in nearly all automotive electrical categories such as Safety, Security, Interconnects, Communication, Charging Topology, and more.
For example, IEC 62196-1 is a standard set by IEC for “plugs, socket-outlets, vehicle connectors, and vehicle inlets” for various EV Charging connectors rated up to 690VAC and 250A. Other international standards commonly utilized for EV-Charging Power connectors are GB/T 20234, SAE J1772, ISO15118, and SAE J3068. Oftentimes, these standards reference each other in an effort to maintain unity around safety principles, as there are many design challenges associated with EV charging connectors and other high-power connectors in the car. For an even deeper look at the global technology landscape for EV chargers, be sure to read our article on the Regulations and Certifications for Electric Vehicles.
What are the Design Challenges for Automotive Power Connectors?
There are a few design challenges that are related to EV charging connectors and other high-power connectors in the car.
Arcing
Protection from unwanted arcing and user shock is generally the highest priority for safety standardization, as both are highly dangerous. Arcing occurs when electric current flows between an energized and non-energized conductor when they are not in direct contact with each other.
High-voltage systems such as EV chargers are prone to arcing if minimum distances between conductive contacts are not maintained, or when a user is unplugging the vehicle from the charging station. Standards such as SAE J1772 (which is commonly used in North America and Japan) includes several safety measures to prevent arcing and shock, such as an integral connector proximity detection pin, a control pilot pin, and a ground pin, to keep high-voltage energized “charging” pins fundamentally disconnected until the connector body is fully mated and the EV signals it is ready for charging.
J1772 connectors are rated to withstand 10,000 mating cycles and exposure to various elements such as rain and snow while still maintaining safe operability.
Safe Mating Options
Automobiles are subject to constant vibrations on the road, and the connectors that support an EV’s powertrain must be impervious to coming loose due to said vibrations. EV power interconnects are commonly used at battery terminals, motor connection point terminals, and power wiring harnesses. There are various types of mechanical interconnecting mechanisms such as lever-locks, sliders, bolt connections, pin-and-sleeve, box-and-blade, and screw locks.
The various automotive power connector types have certain advantages and disadvantages in mating and un-mating use cases, making connector selection critical for EV OEM engineers and designers. Each of these interconnect types must adhere to various safety standards, such as SAE and IEC standards, to ensure they are functional and safe for the life of the vehicle.
Ingress Protection
IP ratings standards cover electronics enclosures and were established in IEC 60529. An electronic's IP rating, or Ingress Protection rating, certifies that an object is able to withstand a specific amount of solid and liquid exposure for a specific amount of time.
Automotive applications range across the spectrum of IP ratings, the most stringent being IP69K. An IP68K rating implies that the enclosure will experience no harmful effects when exposed to dust for 8 hours and/or liquids at high pressure and high temperatures at close range. While IP69K connectors are a rarity, many automotive-rated connectors are IP65-and-above rated, given their expected level of exposure to elements over the life of the vehicle.
To learn more about automotive IP ratings, be sure to check out our article Understanding IP Ratings in Automotive Electronics Manufacturing.
Unified Automotive Connector Standards
Automotive standards unify the global levels of vehicle safety and reliability for all OEMs around the globe. Moreover, EV-specific automotive connector standards allow various OEMs to avoid developing proprietary EV charging connectors and interconnects. This unification of EV power connector topology and safety standards is what fundamentally allows an EV to drive from Portugal to Poland while only needing one charger type, as the various countries between them will all meet the same automotive power connector standards.
Standards such as IEC 62196-1 are created to ensure the operability of connectors used in all imaginable user conditions, and these stringent design criteria often implicate high production costs and possible commoditization of components. However, these high costs often allow individual connector components to be reliable over a long period of time and, most importantly, safe for the vehicle and the driver in nearly any application.
