Charging plug

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New member
Jul 8, 2023
My charging plug just melted the wall socket and blew it out. What would cause that? Should I get a new charging cord?
If the wall socket used those slide-in contact terminals (where the wire insulation is stripped off and the copper wire is shoved into a hole), then i would say that the tiny knife edge contact surface was not sufficient for the prolonged current used during charging. The tiny contact patch created a high-resistance junction that caused local heating and melted the back of the outlet.

i think the screw terminals would provide a better contact surface to carry the current.

The charging cord may not have been affected, although the plug may have some signs of thermal distress; inspect, check and verify that the cord has not been compromised, and replace the plug if it was damaged.
Electrician here...

Like the previous person posted, throw those push terminal plugs out and go for screw terminals! You probably have other outlets on the same circuit , if they are feeding your outlet with push terminals, they too could melt and need to be replaced!

If you can, also replace with a 20a commercial grade outlet (stronger & better plug contacts), instead of the 15A cheapo's. Technically this violates code if you have 14awg wiring supplying it and a 15a breaker (but if 12awg wiring and a 20a breaker, then you are good), so put a label on the outlet cover saying (for 15A use only), and make sure your charger is below 12a.

US wall plug/outlets just aren't designed well enough for sustained high currents. So, I also upgraded my US EV charging outlet to twist lock plugs/sockets, and cut my cord plugs off the chargers and reattached twist locks to them, and use lots of no-ox dielectric grease. Seems silly, but I also made a small outlet plug to twist lock adapter for traveling just in case. This resolved all daily overheating issues.

Lastly, not all EV wall chargers are created equally, look for < 8 - 10amp, or adjustable current chargers. I bought a charger rated at 12a 110v / 16amp - 220v, and that thing roasted so many US plugs/sockets/cords, hence the twist-lock upgrades.

If you need more power and faster charging, upgrade the outlet to 220v, since most level 1 chargers can handle both 110/220v. Might be easier and less costly than you expected, especially if it is the only outlet on the breaker, so then a super easy switch to 220v!

Europe plugs are rated for 16A at 230v, but they still get hot too... The wiring terminals are a bit different (inferior in my opinion) here, so I always use no-ox dielectric grease or solder the wiring to the terminals for best thermal/electrical contact. No melted/blown EU sockets/plugs since the solder mods.

As a techie, this all seems elementary to me, but I get it may be confusing, so just ask if you need help.

Best of luck!
My charging plug just melted the wall socket and blew it out. What would cause that? Should I get a new charging cord?
Where are you? The likely cause of the issue may be related to your location (country) and that country's type of wiring/socket design.

The key question I suspect will be how heavy is the wiring supplying the socket/outlet as the ability to carry current without overheating is 100% related to the gauge/mm2 of the conductors. Secondarily, the thickness of the contacts in the socket/outlet are relevant as is the gauge of conductor in the cable feeding the (portable?) chargepoint. Good quality ones will have a minimum of 2.5mm2 or 13AWG (14AWG in practice). Smaller wires simply won't cope with the heat generated by any sort of poor contact in the socket due to loose/worn or dirty contact connections.

If you intend to continue to use your chargepoint then I would *strongly* suggest you get the socket replaced - and any damaged wiring if necessary - and replace it with a heavier socket. Likewise the plug that supplies the chargepoint *must* be replaced and (obvs) match whatever heavier power/current capable socket you have replaced the original with. Just remove enough heat-damaged cable to ensure a safe repair.
i had assumed that the OP was in the USA, but they didn't say location.

In the US, home outlet AC voltages are 120 or 240.
It has been a few years from the States, & I'm going a bit old school with analog meter averaging still locked in the memory from the 80's. But yes, you are correct, for digital True RMS LCD meters -120/240v in the US. Although, the AVERAGE voltage is still technically about 108-110/220V. Then there is peak (peak to peak) voltage 120/0.707 = 170 V., etc..


Mid-sized city, upper Midwest, US
Thermistors, ok that is a brilliant! Probably a PITA, but brilliant, and should really be in all plugs US/EU. Nice to know BTW, thx!
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