The breaker/fuse manages the flow of electricity to make sure that nothing starts a fire. The wiring should be sized such that it can take a continuous load of 80% of the rating of the breaker, i.e. 24A on a breaker or fuse that allows up to 30A. It should not be possible to create an unsafe situation by charging at 24A on a NEMA 10-30 because the fuse or breaker in the panel should not allow this to happen; if something overdraws, the breaker or fuse should cut the power. Are you sure that this guy was actually an electrician because it sure sounds like he doesn't know what he's talking about. If that circuit cannot take a constant 24A, it's not compliant with the electrical codes.
-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Car charged at higher amps than set. Blew out my fuse box
- Thread starter InigoMontoya
- Start date
-
- Tags
- Charging charging at home
RayK
Active Member
In case you missed my earlier post, you might be able to convert the 10-30 into a 6-20 outlet using an adapter cord. See post #34.
There are a couple of issues if you do this; mainly that the temperature sensor in the NEMA adapter would NOT be located at the 10-30 outlet. However, the charging current would be limited to 16A @ 240V so you can still probably fully recharge overnight.
davewill
Active Member
You can certainly discuss all sorts of options with the landlord, and you probably should rather than try to fly under the radar. The only thing a DryerBuddy would do is allow you to switch between the car and the dryer without the inconvenience of plugging and unplugging. Since you blew the main fuses rather than the ones on the dryer circuit, I'm guessing you didn't have them both plugged in at the same time anyway.
There is a family of devices that monitors the total electric draw and cuts off the car if the house draw gets too high. Here's the link: DCC Electric Vehicle (EV) Charging for Condos or Full Panel Homes
However, they aren't cheap, either to buy or install, and the money would probably be better spent replacing the panel/upgrading the service and putting in a proper charging circuit.
Given the situation, I wouldn't trust the 120v circuits, either. If it were me, I'd ask for an electrial upgrade and offer to pay half and see if he goes for it. However, given the age and condition of the electrical service, it may turn out that doing ANY electrical work will trigger code update requirements that may drive the costs way, way up.
You're right, except for maybe NFPA 70 (NEC) 625.54, which would require that the outlet be GFCI. Assuming the dryer outlet is properly wired with 10awg or larger wire it should handle continuous 24A @ 240V without any issue and be code compliant.
With that being said, it would not surprise me if a smaller wire gauge was used here (even though it wouldn't meet code for the dryer)... 12AWG would only be rated for 16A continuous for example.
Doesn't that only apply for outlets providing power at <= 150V?
Then that would be a code violation and the remedy is to use the proper wire gauge. If the guy who talked to the OP was actually an electrician, he'd know that and he'd know that he's supposed to replace the wiring. For some reason, the OP seems to have reported that this person doesn't believe that the outlet can support a full 24A continuous current, even though it is a 10-30 outlet. Why?
davewill
Active Member
It
Anyway, he would only be required to make updates based on newer code requirements in certain situations. Doing repairs is not typically one of those scenarios.
It was the main fuse that blew. It's entirely possible, even likely, that the dryer circuit CAN handle the charging current, but the house service and/or the panel, can't handle the car in addition to everything else in the house.
Anyway, he would only be required to make updates based on newer code requirements in certain situations. Doing repairs is not typically one of those scenarios.
Last edited:
I've made this mistake in the past too; the old code was super not clear. It was always "<=150V to ground", which a 240V residential outlet almost always is. (Each leg is nominally 120V to ground, even though they're 240V to each other). The 2020 code removed the confusing language and now just says that *any* outlet being used for EV charging must be GFCI protected.
Completely agree.
Maybe ask the electrician/landlord if charging from a 120 volt outlet is feasible. On a recent model 3 you can get 5 or 6 miles per hour that way, which is not ideal but better than nothing…
Good point. Maybe the OP can tell us what else was running. If the main panel can handle 60A, and the car was using 24A, what else was using the >= 36A?
I'm pretty sure that a 10-30 outlet being able to handle 24A of continuous load would have applied even when this particular house was built (and as long as 10-30 outlets have existed). If you were bringing the entire setup up to current code, a 10-30 outlet wouldn't even be allowed -- 14-30 is the current outlet that is used for dryers. But existing 10-30 outlets are grandfathered.
In older houses like the one described in this thread, NEMA 5-15 outlets in garages are often on circuits shared with other stuff, so the maximum (theoretically) safe amperage from one outlet depends on what other stuff is drawing current at the same time on the circuit.
Of course, if the wiring, fuses, panel, etc. in the house are old and decayed, there could be issues even if one is within the maximum (theoretically) safe amperage, a condition known to exist in another part of the house's electrical system.
Similar threads
