| > Do the plugs have any real-world design flaws, or is this just gear snobbery? Design flaws? No. Limitations, yes. A $5 NEMA 14-50R is designed for maybe a few dozen to a few hundred insertion cycles. They’re typically used for ranges (and other fixed equipment) that are plugged in once, and then unplugged once more when you replace the appliance. When the contacts wear out, gaps appear and arcs occur inside the device and it melts. Internal shorts can also happen inside the device. Here’s a tear down video of a residential NEMA 5-15R and a commercial NEMA 5-15R that illustrates some of the shortcomings of cheap wiring devices and shows how more expensive devices have a more robust design: https://youtu.be/kX6xnOksQTc It could also be caused by not using a torque screwdriver to tighten the terminal screws, which is required by the NEC. You must tighten the terminal
screws to the torque value listed in the wiring device instructions, and hold it there for 5 seconds. A loose termination can cause all sorts of nasty problems. There are many grades of wiring devices meant for different applications. More $$ = more durable, better contacts, a full brass strap inside the device, etc. Most people are unaware that multiple grades of wiring devices exist, and also unaware that it can be very important to use the correct one and also install it correctly which requires a torque screwdriver. This is why it’s a good idea to just pay an electrician to do it correctly. Leviton sells a heavy duty NEMA 14-50R specifically designed for plug in EV chargers that are designed to handle many insertion cycles. It costs about $67, but that’s the wiring device you buy if you’re going to be doing a lot of insertion cycles. https://store.leviton.com/products/50-amp-ev-charging-recept... There’s no such thing as a NEMA 14-50R that isn’t rated for a 50A continuous load. It wouldn’t be UL listed if that was the case. |
Probably some people have abnormal use patterns that have them moving a 220v charger around all the time, but I’d bet it’s highly unusual amongst EV owners who charge at home regularly.