How Electrical Capacity Affects EV Charger Performance

Your home’s electrical system must have the right capacity and proper setup to safely and reliably support an EV charger. In the Salt Lake City area, electrical systems are regulated not only by national standards like the NEC, but also by local building codes and utility rules.

In this brief article brought to you by Mr. Electric, we look at how electrical capacity affects EV charger performance and why proper planning and installation matter. If you’d rather consult a certified electrician in South Salt Lake, UT, then call or message Mr. Electric to get in touch today!

What “Electrical Capacity” Means

Your building’s electrical panel distributes electricity to everything in your home or business; think lights, outlets, HVAC, kitchen appliances, water heaters, and so on… Electrical capacity refers to how much your electrical panel can support.

Think of your electrical capacity like a water pipe. The bigger the pipe, the more water can flow through it at once. Your electrical panel works the same way.

Most homes have 100- or 200-amp service panels. A 200-amp panel can handle more electrical demand simultaneously than a 100-amp panel.

Level 2 EV chargers typically require a dedicated 240-volt circuit and a sizeable power draw of around 30–50 amps – or more.

If your panel is already near its capacity, then adding an EV charger without planning can overload the system, trip breakers, or create safety issues like fire hazards and shocks.

Dedicated Circuits Are Required

We are not the only ones who understand the risk of overloading an electrical circuit. EV chargers are considered continuous loads, and the NEC and local Utah codes require chargers to operate on dedicated circuits sized for their specific power draw.

Before installing a charger, an electrician must calculate your home’s electrical load to make sure that there’s enough capacity for the new circuit. Insufficient capacity may mean that your panel needs an upgrade.

Once the electrical panel is confirmed as capable of supporting the electric vehicle charger installation, wiring must be sized correctly. Undersized wiring can overheat, trip breakers, and pose safety hazards.

Electrical Capacity Affects Charging Speed

While safety and legal requirements are most important, electrical capacity also affects the performance of your EV charger.

Level 2 EV chargers deliver power at 240 volts through dedicated circuits ranging from 30 to 60 amps. The higher the amperage, the faster your vehicle charges. A 40-amp charger delivers about 9.6 kilowatts of power, while a 50-amp charger delivers about 12 kilowatts.

But here's the catch: your charger can only perform as well as your electrical system allows. If your home has a 100-amp panel that's already serving other appliances, the charger might not deliver its full power output. That means slower charging times.

Your Options When Capacity Is Limited

For many Salt Lake City homeowners with 200-amp service and modern electrical systems, adding a Level 2 charger is straightforward. The available capacity easily accommodates the new circuit without issues.

But homeowners with 100-amp service or older electrical systems often face different scenarios. Luckily, you're not stuck with slow Level 1 charging. We can recommend a few solutions:

• Panel Upgrade: The most comprehensive solution is upgrading from 100-amp to 200-amp service. This supports not only your EV charger but also some future upgrades you’re considering.
• Load Management Systems: These systems monitor your home's total electrical usage and automatically adjust EV charging power based on available capacity. May not be available for all properties.
• Lower Amperage Charger: Instead of a 50-amp charger, you might install a 30-amp or 40-amp charger that fits within your available capacity.

Hire a Local Electrician Today

If you’re considering an EV charger installation, then make sure to hire qualified pros from a reputable company. The certified electricians at Mr. Electric are uniformed, insured, and regularly trained.

Contact us today to schedule an appointment or even request emergency electrical repair service for as soon as possible.