Don't use a $5 range outlet for EV charging
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Don't use a $5 range outlet for EV charging
1–10 of 35 posts
Re: Don't use a $5 range outlet for EV charging
#2Does this distinction also apply at the lower amps of ordinary 12V plugs? I frequently trickle-charge my EV from an ordinary 12V outlet outside on the porch for 14 hours or more, is that going to be a problem?
(EDIT: sorry, yes, I meant 120V outlet)
Re: Don't use a $5 range outlet for EV charging
#3Does this distinction also apply at the lower amps of ordinary 12V plugs? I frequently trickle-charge my EV from an ordinary 12V outlet outside on the porch for 14 hours or more, is that going to be a problem? (EDIT: sorry, yes, I meant 120V outlet)
I assume you mean 120v outlet, but IMO yes.
One good test that I saw somewhere that I do on new outlets I am charging on, is leave the car charging for ~30 minutes and then quickly unplug the charger from the wall. Touch the prongs to your hands. If they are very warm or hot, you are likely over-drawing that outlet and need to ramp down your amperage draw (or better yet, find a new outlet).
This article focuses on outlets but the wiring is just as (or more) important and outlets can very easily be installed with under-code wiring.
Re: Don't use a $5 range outlet for EV charging
#4[deleted]
Re: Don't use a $5 range outlet for EV charging
#5I hope I'm not too jaded, but this reads really weird to me. The author disses a "$5 range outlet" (even though I don't think they're usually that cheap), then talks about spending several hundred bucks on better outlets for "evaluation"... and the evaluation never comes. We just get a paragraph of innuendo without any real-world testing or even a thorough teardown.
Do the plugs have any real-world design flaws, or is this just gear snobbery? Can the author show that they're heating up too much? Given that there must be hundreds of thousands of home chargers, what's the incidence of problems caused by cheap 240 V plugs?
Re: Don't use a $5 range outlet for EV charging
#6Does this distinction also apply at the lower amps of ordinary 12V plugs? I frequently trickle-charge my EV from an ordinary 12V outlet outside on the porch for 14 hours or more, is that going to be a problem? (EDIT: sorry, yes, I meant 120V outlet)
Yes - likely moreso. (I'm assuming you meant 120v plugs, like US residential.)
The issue in the circuit ampacity for standard residential outlets - typically, a 120v 15 amp plug will be wired in 14 gauge NM-B wire (romex), which already de-rates the maximum temperature the wire jacketing is allowed to reach over higher ampacity wire (THHN) which is typically run in conduit. For a given wire gauge, THHN has more ampacity and the jacket is rated to a higher temperature.
for a 20amp 120v circuit (not common unless you install intentionally for that purpose) you need 12 gauge wire.
But, as mentioned in the article, continuous loads need to be up-sized because of temperature, and even standard outlets for the correct ampacity circuit don't often anticipate 100% duty cycle.
BUT, the real question is for your trickle charger, how many amps does it draw? if it tries to draw 12 amps on a 15amp circuit, everything is fine. If it tries to draw 15-20 amps on a 15 amp circuit, there is some danger. Many breakers (esp older ones) will not actually pop if the amp demand ramps up slowly.
Ampacity Charts: https://www.cerrowire.com/products/resources/tables-calculat...
Source: I've wired a LOT of power tools with big loads, but I am not an electrician. Take this advise as indicative and decide whether it warrants you contacting an electrician to validate your situation.
Re: Don't use a $5 range outlet for EV charging
#7Does this distinction also apply at the lower amps of ordinary 12V plugs? I frequently trickle-charge my EV from an ordinary 12V outlet outside on the porch for 14 hours or more, is that going to be a problem? (EDIT: sorry, yes, I meant 120V outlet)
Yes - likely moreso. (I'm assuming you meant 120v plugs, like US residential.) The issue in the circuit ampacity for standard residential outlets - typically, a 120v 15 amp plug will be wired in 14 gauge NM-B wire (romex), which already de-rates the maximum temperature the wire jacketing is allowed to reach over higher ampacity wire (THHN) which is typically run in conduit. For a given wire gauge, THHN has more ampac…
Car chargers only pull 12A from a 15A circuit.
Re: Don't use a $5 range outlet for EV charging
#8I hope I'm not too jaded, but this reads really weird to me. The author disses a "$5 range outlet" (even though I don't think they're usually that cheap), then talks about spending several hundred bucks on better outlets for "evaluation"... and the evaluation never comes. We just get a paragraph of innuendo without any real-world testing or even a thorough teardown. Do the plugs have any real-world design flaws, or i…
It's not hard to find pictures online of melted NEMA 14-50 outlets. Design flaw or loose connection? Some will definitely be the latter, but all? Who knows? I'd spend the extra $50.
Or set your car to only pull 24A from the outlet rather than full speed. Still more than fast enough to full charge overnight.
Re: Don't use a $5 range outlet for EV charging
#9Earlier quoted context omitted.
Yes - likely moreso. (I'm assuming you meant 120v plugs, like US residential.) The issue in the circuit ampacity for standard residential outlets - typically, a 120v 15 amp plug will be wired in 14 gauge NM-B wire (romex), which already de-rates the maximum temperature the wire jacketing is allowed to reach over higher ampacity wire (THHN) which is typically run in conduit. For a given wire gauge, THHN has more ampac…
Car chargers only pull 12A from a 15A circuit.
Yeah - you'll see that I mentioned that - if that is true, then great. But, IMO, it's worth verifying. Even more worth double checking if the building is old, or an extension cord is involved.
Re: Don't use a $5 range outlet for EV charging
#10Earlier quoted context omitted.
Car chargers only pull 12A from a 15A circuit.
Yeah - you'll see that I mentioned that - if that is true, then great. But, IMO, it's worth verifying. Even more worth double checking if the building is old, or an extension cord is involved.
Yes, the one time I used an extension cord to charge the car, I set the max amperage to 8 even though it was a 15Amp rated cord.