Motor Trend article on GFCI for EV chargers in upcoming NEC

[Yikes]

https://www.motortrend.com/news/national-electric-code-revision-threatens-ev-charging/​

Dumb New Electrical Code Could Doom Most Common EV Charging​

A coming ground-fault circuit-interrupter revision could make slow-charging your car nearly impossible.
Frank Markus Writer
Getty Images Photographer
Jan 22, 2025


The National Fire Protection Agency (NFPA) publishes a new National Electric Code every three years, and we almost never notice or care. But the next one, NFPA 70 2026, has the Society of Automotive Engineers (SAE) electric-vehicle charging subcommittee, OEMs, and companies in the EV Supply Equipment (EVSE, or charger) biz mightily concerned. That’s because it proposes to require the same exact ground-fault circuit-interrupter protection that makes you push that little button on your bathroom outlet every time the curling iron won’t heat up. Only now, that reset button will often be down in an electric panel, maybe locked in a room where you can’t reset it. If EV drivers can’t reliably plug in and expect their cars to charge overnight at home or while at work, those cars will become far less practical.

Why GFCI?​

We’ve all probably felt a jolt of electrical current at some point in our lives. If so, your body basically completed a circuit between a live wire or outlet and the ground. Just 40 milliamps of AC current (or 300–500 mA of DC at high voltage) can cause cardiac fibrillation.

What a ground-fault circuit-interrupter (GFCI) does is constantly monitor the current flowing back and forth on a circuit’s “hot” and “neutral” (often black and white) wires. Any difference detected is presumed to be a person grounding some electricity and causes the circuit to break. In North America, those 120-volt kitchen, bath, and outdoor GFCIs get tripped by just 5 mA (in Europe, the trigger is 30 mA). Fun fact: Sometimes the simple presence of water on the cable or connector can bleed enough current to trip these circuits (ever had Christmas lights suddenly blink out in the rain or heavy dew?).

The Case for 5 vs 30 Milliamps​

Touching a live wire typically makes one involuntarily flinch—quite possibly hard enough to knock one off a ladder if, for example, that jolt occurs while hanging your cheap Christmas lights. When the circuit switches off at 5 mA, the lights go off after just a tiny jolt and you hopefully remain on the ladder. Given the assortment of old, poorly maintained consumer stuff that can be plugged in to a 120-volt plug, the 5 mA limit makes pretty good sense at this voltage level.

The Case Against 5 mA​

In 2020, the national code started requiring GFCI protection on 240-volt plug receptacles, still with the same CCID5 (4–6mA) trip threshold. Well, bigger equipment of the sort that plugs into these NEMA 6-20, 14-50, etc. outlets draws more power and naturally experiences larger current fluctuations. These can cause “nuisance trips.” But because these 240-volt outlets are often located behind heavy equipment, the reset button is not permitted to be on the outlet face. It must be in an accessible location, though that is likely to be at the distribution panel, possibly in a locked room somewhere.



As a work-around, EVSE manufacturers started directing users away from plug-in to direct hard-wired installations. But now the code is shifting to require GFCI protection even for hard-wired equipment. And a 5mA trip is way too low for a circuit that may supply more than one Level 2 charger. Keep in mind, these are the most common chargers, a step up from simply plugging into a 120-volt wall outlet but short of Level 3 DC fast chargers typically found in public charging stations, that are installed at homes, businesses, and car dealerships.

EV Chargers Provide Their Own Protection​

The national code doesn’t care what you’re plugging in, but vehicle chargers deserve their own carve-out. That’s because no current ever flows until the charger has verified a solid ground connection from car to charger and from charger to electrical panel. They also include their own GFPE (Ground Fault Protection of Equipment), which is intended to protect equipment and is permitted to trip at values larger than 5mA, often in the 15–20mA range. That’s why this new code REALLY needs to set a higher supply-side cutout (like what is allowed for marine vehicle shore power, which is up to 30mA). Because even if the Special Purpose GFCI with its 15–20mA trip level were allowed, it would be a 50/50 chance that any fault would trip the electrical-supply breaker or the device’s internal breaker. But while the device is programmed to automatically reset and try again, the panel requires a manual reset. There is one EV-charger carve-out: Bi-directional chargers are exempt.

Timeline To Trouble​

This problematic application of 5 mA trip to most 240-volt equipment was added into this regulation late, during a second draft, and now the only way to head it off is for interested parties (SAE, OEMs, and EVSE manufacturers) to register their notice of motion in February for consideration in March. This isn’t a government regulation, so it’s utterly unaffected by the change in federal administration. These are functionary folks with minimal experience of EV charging, so the arguments must aim to convince the NFPA that implementing this code as is could grossly embarrass the Agency. (Understanding that any such embarrassment will only arise after buildings and projects are completed under the new code.)

A Precedent for Embarrassment?​

In 2005, some faulty repair work done on an air-conditioning compressor resulted in the metal enclosure of the condenser being electrified. A boy hopping over a fence contacted both the enclosure and the fence and was fatally electrocuted. This prompted a code change requiring GFCI protection—with a 5mA trip threshold—for HVAC units. Some time later, during a hot spell in Texas, numerous spurious circuit trips made it impossible to cool enough buildings that this line item was crossed out of the code in a number of states.

What You Can Do​

Sadly, not much. Contacting your state or local legislators won’t help, as they’re not directly involved. Cross your fingers and say a little prayer for the industry cognoscenti to make a convincing case in March.

 

[Joe.B]

Yeah, they raise some good points. Unfortunately, they're perpetuating a common misunderstanding of how electricity works, but most people will never know or care. Statements like "your body completed a circuit between a live wire or outlet and the ground" drives me crazy. For lay people, fine, but I can't tell you how many inspectors, electricians, engineers, etc. believe that electricity "goes to ground." Simply not true.

 

[steveray]

Finally the electric code does something good...I'm sure the lobbyists will buy their way through shortly....

 

[sclavette]

Maybe the manufacturer's should create a product that doesn't cause the GFCI to trip? The GFCIs are simply doing what they are designed to do.

 

[Paul Sweet]

I think the main concern is the location of the GFCI. The article says it has to be a GFCI breaker in the electric panel, and the panel feeding a commercial charger wouldn't be accessible to people using the charger. It would be good if a 5ma GFCI in the charger was also acceptable.

 

[steveray]

and the panel feeding a commercial charger wouldn't be accessible to people using the charger. I

240.24 should take care of that....

 

[wwhitney]

Maybe the manufacturer's should create a product that doesn't cause the GFCI to trip?

That would be up to the EV manufacturers, the EVSE is just a slightly smart switch.

The GFCIs are simply doing what they are designed to do.

Not necessarily. If the 5ma of current is from capacitive coupling occurring somewhere within the EV or the cord between the EVSE and the EV, then I don't believe it is actually a shock hazard, and it is reasonable to say the GFCI is nuisance tripping. Likewise if the tripping is due to a high frequency noise signal that the EV's on-board charger is leaking, causing the GFCI to trip at a current level below what the standard requires. This latter issue I believe sometimes occurs on other equipment that incorporate ECM motors or VFDs, like some clothes washers, some HVAC units, etc.

Cheers, Wayne

 

[steveray]

I believe the higher threshold is coming for 2026 or 2029…for certain appliances/ locations. Which makes no sense in the “ you can get a higher shock over here than over there” way…

 

[Yikes]

Yeah, they raise some good points. Unfortunately, they're perpetuating a common misunderstanding of how electricity works, but most people will never know or care. Statements like "your body completed a circuit between a live wire or outlet and the ground" drives me crazy. For lay people, fine, but I can't tell you how many inspectors, electricians, engineers, etc. believe that electricity "goes to ground." Simply not true.

Show them this: