National Electrical Code Top Ten Tips: Article 625, Electrical Vehicle Charging System
Coal-powered cars, commonly called "EV" or electric vehicles, are the
dirtiest, most energy-consuming form of personal transportation in existence
today. The common wisdom, or lack thereof, is that somehow electric power is
free and is generated without any pollution whatsoever, if it's stored in toxic
batteries (the lithium for which is energy-intensive to obtain) and then used to
power a vehicle. Due to this utter nonsense, politicians are touting electric
vehicles as some sort of solution to a host of problems they merely exacerbate.
So instead of using electric vehicles only in the limited applications for
which they make sense, schemes are now underway to use them in place of internal
combustion engine cars. This means more electrical vehicle charging system work
for electricians. It also means faster depletion of worldwide oil reserves and
more pollution, but that's a subject for a different Website. Here are your ten
- Article 625 covers the charging equipment external to the vehicle. It
covers anything you will install or wire up, if it connects the vehicle to premises wiring for charging the
vehicle or to export or transfer power [625.1].
- In 625.2, Article 625 used to day it is for on the road vehicles, not golf carts and the like for off
road use, and not for hybrids. That was in the defintion of "Electric Vehicle". In the 2017 revision, the definition was still in 625.2. With the 2020 revision, that definition moved to Article 100.
- Don't "invent" or "design" connectors, enclosures, or other equipment or
devices in this installation. It must be listed and labeled, or it can't be used
- Part II addresses the permissible wiring methods. They are essentially the
responsibility of the manufacturer. The installer needs to observe plug
configurations and connector kit instructions to ensure compliance.
Part III provides the equipment installation requirements. They are
- Size the overcurrent protection for continuous duty. Ensure it has a rating
of at least 125% of the maximum load of the EV supply equipment [625.41].
- If the charger is 60A or larger or more than 150V (to ground), you must
install a disconnect in a readily accessible location. It must be capable of
being locked in the open position [625.43].
- You must provide a means to prevent backfeed to the utility, in the event of
loss of utility power. This should be included in the charger kit; ensure it's
properly connected [625.46].
- For indoor installations, you'll find the minimum ventilation requirements
in Tables 625.52(B)(1)(a) and .625.52(B)(1)(b).
- For outdoor installations, the coupling means must be stored or located at
least 2 ft but not more than 4 ft above the parking surface [625.50].