Over the last 20 years all new homes have been outfitted with GFI, Ground Fault Circuit Interrupter in places like the bathroom, laundry area, and outdoor outlets. In many jurisdictions the use of surge protection is required or highly recommended.  All these devices are designed to increase safety and minimize accidents when devices are connected to the electrical infrastructure.

An EV charger or EVSE (EV Supply Equipment) is an electrical device like a TV, computer, fridge, stove, and so on that is used to deliver electricity to your car’s batteries. EVSE like most modern technology, are vulnerable to surges in utility power voltage. They can damage or destroy EV equipment.

What are power surges?

Power surges are short spikes in voltage on the electrical system caused by power grid equipment switching on or off, lightning strikes, and other events. The extra jolt of electricity can fry electronics connected to your home’s wiring.  Power surges can target home electronics, appliances, and EV chargers as well.  

Why your EV charger needs protection?

EV home chargers rely on advanced circuitry to safely and efficiently charge your electric car’s battery. A power surge can overload and permanently damage those components. Surge protectors (SPD) prevent costly damage by blocking excess voltage before it reaches your EV supply equipment. They quickly divert the spike to ground and lower the voltage to a safe level.  Like GFI outlets all over your home. They allow you to use your hair dryer, curling iron, etc. safely. And it is not just huge, sudden surges that cause problems. Smaller fluctuations over time will eventually degrade your EV charger and batteries.

Changes in regulation!

UK - EV chargers along with other new electrical circuits require surge protection to comply with the technical aspects of the 18th Edition Amendment 2 of the Wiring Regulations. 

Germany - In June 2019, the German national standard adopted the 2018 IEC 60364-7-722 revision that includes Requirements for Special Installations and Locations: It is now mandatory that suppliers of Electric Vehicle (EV) charging infrastructure install surge protection to ensure safe operation for the public and to protect the infrastructure from being damaged due to transient over voltages.

International - IEC 60364-7-722 mandates that SPDs be installed, not only to protect the infrastructure, but also to ensure personnel safety by limiting dangerous voltage potentials.

USA - The 2020 National Electric Code, Section 230.67, requires SPDs for all dwelling unit electrical services. Specifically, it calls for a Type 1 or Type 2 whole-home SPD to protect your main panel.

Home and AC chargers exposed!

DC Fast Chargers are certified to UL 2202 standard with surge protection. While residential and many commercial AC chargers are installed outdoors, they are certified to a different standard in North America than those of DC Fast Charger and do not require surge protection. It’s still possible that residential or AC chargers require surge protection, but any requirement will fall under other regulation, as noted above.  

Finally, be sure to check your EV warranty. Charging an EV battery without an SPD may void your warranty.

SPDs are relatively inexpensive devices and don’t require any changes to your house wiring.  Proper installation by a qualified electrician is key to optimum performance. The SPD ground connection should use a dedicated conductor to established building/service ground. Shorter wire runs between the SPD and supply conductors provide better surge response.

By following the steps above and working with qualified professionals, you can help ensure that your electric vehicle charging system is safe and reliable.