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115v charging

115v charging

Hello again. I charge from a 115/120 VAC outlet in my garage and as I charge 5 or more times a week and I tend not to drive >200 miles weekly all is fine for me. Today I realized that my charge rate is 4.1 - 4.3 and hardly changes. My house is 30 years old with 200AMP service and I have 30 amp breakers for AC,clothes dryer, the Hot water heater and multiple 20 AMP breakers for things like the refrigerator. However, for bedrooms and the garage they are 15 amps. As changing one breaker is brainless, would this be a sensible thing for me to do. Surely, I would rather have a quicker charge rate for pocket change. Please tell me if this is a mistake.

VolleyballNE1 | 28 May, 2019

It's not as simple as changing a breaker. Your electrician probably put in a breaker for the max the wire will allow before a fire results from overcurrent for the wire thickness. So it is a good idea to install a NEMA 14-50 outlet and the associated wires. Just don't change the breaker without changing the wires!

Daryl | 28 May, 2019

I did replace a 15A breaker with a 20A, but first confirmed that the wires on both ends were a compatible gauge.
Be careful, it might void your home owners insurance if there is an electrical fire.

Neomaxizoomdweebie | 28 May, 2019

I had a pro put a 14-50 socket in right under my breaker box. I’m charging at 30 mph with this setup. My breaker box is in my garage next to my car. Hopefully you have this setup. $300 with a top recommended electrician from Angie’s List.

Slonkis | 28 May, 2019

I second Neo's recommendation. Really easy set up, very reasonable cost, and flexibility to charge faster when necessary.

FlyingCircusNH | 28 May, 2019

Third on Neo's. I had a trusted electrician install a 50A wire, plug and circuit (what homes really need for the clothes dryer) for $300-$400. The 50A wire has about an 80 foot run. If you want to save $, run the wire near the box and the garage yourself and leave the circuit panel connection and the garage plug connection to the electrician. The sw limits the draw to 32A, which ends up being 31-32 miles of charge/hour. I'm recharging my 80 mile daily draw (70 mile commute) in under 3 hours.

Tronguy | 28 May, 2019

Aaannd a warning. The 115 VAC sockets and very likely the wires in your garage are rated for 15 A in extremis. Go higher than that and one or the other, in steady state, will Catch on Goddam Fire. 20 A sockets are recognizable by the ability to accept a plug where one of the blades is at right angles to normal; in such a case, the socket, the wire in the wall, the breaker, and the plug one uses are all rated at 20A and won't burn up. Note that the heavier gauge wire costs more so, if an electrician has put in a 15A breaker on a circuit, he's likely using 15A wire as well.
Moral: Don't go swapping sockets and breakers for bigger amperage types without being Really Sure the right gauge wire is back there, too. This isn't rocket science, and there really is a point to all this: not burning the house down in the dead of the night with your loved ones in it.
Final mention: as you probably noticed. The car only pulls 12A on a 15A circuit. That's an 80% reduction of the peak load current and is by design. And it's true in general. Use a TWC with a car that can draw 48A from the city, and you'll need 60A wire and breaker.
Be safe, burning up is a lousy way to go.

c_birkett | 28 May, 2019

I got a couple of quotes and it was $1,500 for an electrician to move an existing 50 A circuit from my unused oven outlet to my garage - 20' or so. So I'm doing the job myself, someday. But for the last 5 months I've been charging on a 20 A circuit and it gives me 5mph. With my commuting schedule this means maybe once a month I consider supercharging. Wish I hadn't bought all the 6 ga wire n supplies now. I REALLY am fine on 110.

Tronguy | 28 May, 2019

The SO and I were lucky. The 200A breaker panel is in the garage and right next to the Tesla. If we had wanted to put the TWC next to the panel, could've done that but would have had to coul/uncool the cable each time across the rear of the car. Instead, paid an electrician a couple hundred to run a feed up, over, and down between the two cars.
Nice job, and got ot inspected, too.

rfpmoxie | 28 May, 2019

Thanks folks and I DEFINITELY will not make a change.

lbowroom | 28 May, 2019

Yes, because there is absolutely no margin of tolerance built into that rating. The moment you draw 16A through a 15A circuit, the house will explode and melt to the ground

Tronguy | 28 May, 2019

Lbmm@lbowroom: yup, sarcasm. And, yes, all those NESIC plugs got magin, so do the wires, and so do the breakers. In a nice, clean installation, one can probably drow 20, 25A at 120 and probably do so for years without smoking the house. Millions of hillbilly electricians would agree with you and wire up three, four more so CV let's because, hell, it's worked OK so far, right?
Add age, plastic degradation. Insulation degradation, ants, leaks, cat piss, roaches, dirt, nearby lightning strikes, th he odd heavy rainstorm, it'll be juuussst fine, no problemo.
A civil engineer friend of mine once remarked that for the National Building Code, thos thousand+ tomb, each page was there for a fallen down house.
One can play fast and loose or one can sleep at night, I figure. I prefer to sleep.

echidna | 30 May, 2019

I made a switchbox that plugs into the electric dryer outlet in my garage. Dryer cord with 3-prong plug for old-style dryer outlet, two dryer sockets, and a 40A 240V DPDT switch. Ordered the appropriate plug for the charger from Tesla. Put it all into a big electrical junction box and hung it on the wall. Plugged the switchbox cord into the wall outlet, the dryer into one switchbox outlet and the Tesla charger into the other.. Whole thing cost a little over $100.

Works fine, and charges at 25 range-miles per hour. You'd think these would be offered for sale, but I couldn't find one on line.

kevin_rf | 30 May, 2019

An option that is little more involved than changing a breaker. If this is the only on the breaker. More than one and you would have to disconnect the other outlets.

It is possible to convert from a NEMA 5-15 (standard 120v outlet) to a 240v NEMA 6-15 outlet. This involves changing the breaker and outlets hanging off the breaker.

Tesla does sell an adapter, and you'll be able to charge at a whole 11 miles an hour.

Based on your earlier question, I would have an electrician do the conversion. It might cost the same as just installing a NEMA 14-50.