Help identifying outlet

[dsb411]

Buying a 3 year old house with this outlet in the garage. I thought it was for previous owners golf cart, but that plugs in elsewhere. This for a boat or a trailer? Anyone use this type of outlet to charge? Can I use it to charge my Y any faster than a regular 110 outlet? I’ve found an adapter that can connect to my mobile charger via my NEMA 14-50 connector, willI catch anything on fire?

 

[21miDay]

I find this site is always helpful: CarCharging.us
Yours is a TT-30 and is pictured in the right column, fourth one down.
The table on this page gives you an idea of the charging speeds for different Amps. For Tesla Model S, Model 3, Model X, & Model Y Gen 2 – EVSE Adapters

This adapter is made for your mobile connector. I have one and have used it at an RV park. TT-30 Adapter for Tesla Model S/X/3/Y Gen 2 – EVSE Adapters

Will you burn anything down? That depends if it is wired correctly.

 

[dsb411]

Awesome! Thank you for this great info!
How fast does it charge?

 

[Silicon Desert]

The interesting thing to me is the label "125" vac. For the last several decades in America, it has been either 120 or 240, but I see people referring to it as 110, and now this 125 label. Yea, we all know what we are referring too though.

And yes a 30 amp circuit will charge faster than a typical 15 amp or 20 amp one. Actually, I would look to see if you have a 240 circuit in the garage for charging if you plan not to add a wall charger.

 

[21miDay]

How fast does it charge?

I only know what is in the table and it doesn't include the Y. If you look at the table, the difference between the normal household 15A and the 30A is roughly 3 to 5 Miles of range per hour depending on which car you are looking at.

 

[Sophias_dad]

30 amps gives you 24 amps usable, times 240 volts is 5760w, which divided by ~275w/mi becomes just under 21 mi/hr, probably 20mi/hr is more realistic with the overhead of charging.

 

[jsmay311]

30 amps gives you 24 amps usable, times 240 volts is 5760w, which divided by ~275w/mi becomes just under 21 mi/hr, probably 20mi/hr is more realistic with the overhead of charging.

Except it’s not 240V.

 

[Sophias_dad]

Except it’s not 240V.

Yep, a rather anemic 120V. Sorry for the misinformation.

The good news is that outlet is virtually guaranteed to be on a dedicated circuit, and could most likely be changed to a 6-30 outlet in minutes. A new breaker(assuming there's space in the panel, or it could be made), two pieces of red electrical tape for the white(neutral) wire, and a new outlet is all that's needed.

 

[Tronguy]

Buying a 3 year old house with this outlet in the garage. I thought it was for previous owners golf cart, but that plugs in elsewhere. This for a boat or a trailer? Anyone use this type of outlet to charge? Can I use it to charge my Y any faster than a regular 110 outlet? I’ve found an adapter that can connect to my mobile charger via my NEMA 14-50 connector, willI catch anything on fire?

View attachment 888986View attachment 888986

Yeah, adapter for a NEMA14-50 connector. Um. Not a good idea. In fact, a very bad idea.

Here's my go-to plot of this and that: File:NEMA simplified pins.svg - Wikipedia

So, my general understanding of how a NEMA14-50 is used, at least in 240 VAC applications, is that one pin is safety GND, one pin is Neutral, and the other two pins are 120 VAC, 180 degrees out of phase with each other, so that the voltage between them is 240 VAC.

This mimics rather closely how houses in the US/Canada are wired: Each house tends to get split phase power, with two hots, each 120 to neutral, and 240 between the two hots. At the breaker panel, alternating horizontal slots get one hot or the other. A single-width breaker provides a single hot at 120 to neutral/ground (those latter two are bonded together at the main breaker panel); a double-width breaker provides two hots with 240 VAC between the hots, for use when charging electric cars, running a clothes drier, or the furnace blower/air conditioning system.

As others have noted, your socket is a NEMATT-30. The roundy top pin is safety ground, the bottom left blade is a 120 VAC hot, and the bottom right blade is Neutral. There's no 120 VAC anywhere near this thing.

The NEMA14-50 adapter in your Mobile Connector kit is expecting 240VAC/208VAC (depending upon whether your house is powered for split phase or three phase, respectively), and nothing else but.

So, deep breath: Say one has an RV. The RV is likely wired like a house, and whatever passes for a breaker panel in the RV is expecting two hot phases and a neutral. The neutral gets connected to this heavy bus bar. A NEMA14-50 connects to two hots; each of those two hots goes to each of two additional bus bars, and those two bus bars connect to alternating slots where the breakers plug in. So, take a breaker, plug it into a slot, and there's a terminal where a wire plugs in to the breaker on one end and goes to whatever-it-is (like, say, the lights or a socket) at the other end, and there's 120 VAC between that hot wire coming off the breaker and the neutral bus.

Plug said breaker into the next slot and, instead of getting hot A (say), one gets hot B. which is also 120 VAC to neutral.

Now, get a double-wide breaker that plugs into two slots, there's two wires coming out. Since Phase A and Phase B are of opposite phase, there's 240 VAC between those two wires - and each wire is 120 VAC to neutral.

Now, suppose one has some load that needs 120 VAC at 30A. Haul out the TT-30, which is hot, neutral, and ground, and the hot is 120 VAC to neutral and install that; why not, it's a legit 120 VAC, 30A circuit. Next, say one has an RV that happens to have no 240 VAC loads, or one doesn't care about the 240 VAC loads. One gets a funky adapter that connects the one and only hot on the TT-30 to both of the hots on a NEMA14-50, and plugs the RV into that. Well... the 120 VAC sockets and lights will work in the RV, but any 240 VAC loads will have Zero volts into them, since the two phases on the two hot connectors of the NEMA14-50 adapter in this case are the same wire/phase, and has zero volts across the 240 VAC load. No Air Conditioning for You, and the clothes drier in the RV won't be working, thank you very much. But you'll have lights, and maybe the microwave will work, so, why not?

But... if you use that funky adapter that you mentioned, what you'll get when you try to charge the Tesla is... nothing. The car won't see any voltage, or (alternatively) it'll see something weird with the voltages to ground/neutral, and will throw a fault.

The only two strictly 120 VAC adapters available for the Gen 2 Mobile Connector is one for a NEMA5-15 (good for 12A on a 120 circuit with a 15A breaker) or one for a NEMA5-20, which has a right-angle blade, and is good for 16A on a 120 circuit with a 20A breaker.

Typical charge speeds for those two 120 VAC adapters is 4-5 miles of charge per hour with the NEMA5-15 and 4-6 with the NEMA5-20: See the site, https://shop.tesla.com/product/gen-2-nema-adapters.

A better bet, as has been noted here, is to snag oneself an electrician, ditch the TT-30 connector, get some heavier wire and put in an actual NEMA5-50 with a 60A breaker behind it at 240 VAC. With the Mobile Connector, you'll get a maximum of 30A. If you want better, you either get a Tesla Wall Connector, which, with a 60A circuit, can do 48A, or some other party's J1210 wall connector, and use that, at whatever current it can do (the car's max is 48A).

 

[Tronguy]

Buying a 3 year old house with this outlet in the garage. I thought it was for previous owners golf cart, but that plugs in elsewhere. This for a boat or a trailer? Anyone use this type of outlet to charge? Can I use it to charge my Y any faster than a regular 110 outlet? I’ve found an adapter that can connect to my mobile charger via my NEMA 14-50 connector, willI catch anything on fire?

View attachment 888986View attachment 888986

Oh, yeah, one last thing. Note that warning message: Turn Off The Breaker Before Moving Said Plug Around. I'm not an electrician, but I can read between the lines: 30A on a hot/neutral is a Lot Of Current. Pull the cord out of the wall (like people do with vacuum cleaners all the time), but this time, let's have a Great Big Motor running out there. The inductive kick from turning off that motor by pulling the plug out of the socket with a load present will likely make a $DIETY's-own-flash/arc, and neither the socket nor the plug will like the experience. Hence, the warning.

 

[dsb411]

Oh, yeah, one last thing. Note that warning message: Turn Off The Breaker Before Moving Said Plug Around.

I thank you for your posts even though I have no idea what you are talking about. Will this work or not? TT-30 Adapter for Tesla Model S/X/3/Y Gen 2 – EVSE Adapters

 

[henderrj]

Should, yes. If you have 10 hours of charging a night and drive less than a hundred miles a day, it'll probably do for the rest of your life.

You won't be able to top off your battery fast ever, but normally that's not an issue.

 

[Tronguy]

I thank you for your posts even though I have no idea what you are talking about. Will this work or not? TT-30 Adapter for Tesla Model S/X/3/Y Gen 2 – EVSE Adapters

Ok. The adapter looks legit, even if it’s non-Tesla: it’s designed for a Gen2 UMC and even has the temperature sensor. This is a lot better than what I thought you had in mind, some kind of hacked-together TT-30 to 14-50 adapter.

But.. you’re still playing at what people call Level 1, 120VAC. So this may work for you or it might not. Let’s hit the salient points.

First, let's hit the easy parts. Rule: There's always a current limit somewhere. The lowest current limit in the chain of things Always Wins.

1. The car takes Level 2 or Level 1 AC voltages (240 VAC or 120 VAC) and converts it to DC to Charge Ye Battery. The car has a current limit of either 32 Amps (Standard Range) or 48 Amps (Long Range or P).
2. The UMC cable can do 32A, max.
3. The various circuits in a house have limits; for the heavy, continuous loads that a Tesla draws, this circuit limit varies depending upon the outlet:
   1. NEMA5-15 is a 15A circuit, with breaker, wire, and socket all rated for 15A, max current is 80% of that, or 12A. Standard wall outlet. 120 VAC, Level 1.
   2. NEMA5-20 is a 20A circuit, with breaker, wire, and socket all rated for 20A, max current is 80% of that, or 16A. Odd looking standard wall outlet with one blade at right angles. 120 VAC, Level 1.
   3. NEMATT-30 is a 30A circuit. Maximum current draw is 24A at 120 VAC, Level 1.
   4. A plethora of different 240 VAC sockets, with that NEMA14-50 in there, all at Level 2. NEMA14-50's properly installed can do 40A for a Tesla, but there's two issues: Somewhere in the NEC code there's some subclause saying it's legit to put a 40A breaker on a NEMA14-50 socket, right along with 40A wire, for clothes driers that are rated for 40A 240 VAC. Such a circuit would have a max current of 80% of 40A, or 32A. The second issue is that even if one has a NEMA14-50 adapter plugged into a Tesla UMC, the UMC itself can't handle more than 32A, anyway, so one is never going to see that 40A max in any case. (Remember: Lowest current limit wins.)

Now, power. First, you've got the efficiency of the car. I have a MY-LR and a M3-LR in the garage. The MY gets 280 W-hr/mile; the M3 gets 250 W-hr/mile. Your car, dunno. The SR, LR, and P variants all have slight differences in their efficiencies. Let's say you've got the MY-LR.

There are some losses in charging the car, but they're small. Let's just do the back-of-the-envelope math.

Charge Rate in Miles Per Hour = Charging_Power/Car_Efficiency. So, if one was charging at 1000W and had my M3, you'd be charging at a rate of 1000W/(250 W-hr/mile) = 4 miles of charge per hour.

Adapter	Voltage (V)	Current (A)	Power (Watts)	Charge Rate (Miles of charge per hour)
NEMA5-15	120	12	1440	5.1
NEMA5-20	120	16	1920	6.9
NEMATT-30	120	24	2880	10.2
NEMA6-15	240	12	2880	10.2
NEMA6-20	240	16	3840	13.7
NEMA10-30, NEMA14-30	240	24	5760	20.6
NEMA14-50, NEMA6-50	240	32 (limited by UMC)	7680	27.4
Tesla Wall Connector with MY SR	240	32 (limit is the car)	7680	27.4
Tesla Wall Connector with MY LR or P	240	48 (with 60A circuit, limit is the car)	11520	41

So, this is the point where one has to look at one's navel and decide how one's driving habits and sleep times affect things. Say one has 200 miles of charging to do. With the NEMA5-15 (worst case, standard U.S. wall socket) it's going to take 200 miles/5.1 miles per hour = 39.2 hours. And, if it's cold out and the car has to get its battery warmed up, that rate might drop to a mile or two per hour. (I've actually had this happen with 20F weather and a heavy-duty extension cord at a friend's house. 12A, yeah, but a very low charge rate.)

With a TT-30 adapter, 200 miles/10.2 = about 20 hours. Well, that's better, and once the car gets warmed up in cold weather (takes about a kW for a half-hour or so) it'll chug right along at that rate.

Say one gets an electrician in and puts in a new socket, or converts the old and makes things run at 240 VAC. With a 32A socket (14-50 or 6-50), you'll gt 27.4 Miles of Charge per hour; for 200 miles, that's 200/27.4 = 7.3 hours. That's definitely overnight and won't get in the way of one's commute. I mean, one has to sleep sometime.

Back in 2018 I looked at all this and figured that the cost of a Wall Connector and the electrician was simply part of the price of a car. Luckily, the breaker box for the house was in the garage and the box had plenty of spare capacity. The Gen 2 Wall Connector can do more than 48A (there is, apparently, a 200A setting in the switches!), but the cars in the garage max out at 48A. So, with a 200 mile charge, the MY can do that in 200/41 = 4.87 hours; the M3 charges at 46 Miles per Hour, and can do that 200 mile charge at 200/46 = 4.34 hours.

But this is where the navel-gazing is important. Say one drives an average of 50 miles a day. Plug into the TT-30 when one is home and it can definitely keep ahead of what energy one is using. If one is going on a trip, well, keeping the car plugged in and setting the limit to 100% with a departure time the next day will work and all.

The other trick is that one doesn't need to always be charging. I'll charge the M3 to 80% (around 240 miles or so these days), then run around the landscape for the next few days until it's down less than 100 miles, then charge again.

The advantage of having a Level 2 (that is, a 240 VAC) connection of 32A and up means simply that one doesn't have to think much about charging the car. Plug it in when one gets home when the charge is low and the car'll be ready in the morning. At Level 1, well, it can be done, and lots of people do it, but one has to apply a bit more forethought, that's all.

Finally: These days, the cost of a Tesla WC is low enough that, if one is going to put in a 240 VAC circuit, the cost of the WC is about the same as the cost of the NEMA14-50 socket and the required Ground Fault detector, the latter required by code in many jurisdictions. And, no question, a Wall Connector is convenient: It stays on the wall, the cable hangs nicely over the thing and it has a place for the end of the cable, the UMC stays in the trunk, where $DIETY intended it to live, and the whole business gets more reliable, since the only moving part in the whole business is the contactor inside the WC, which only switches on and off when the current is zero.

Your call.

 

[ai4px]

Yep, a rather anemic 120V. Sorry for the misinformation.

The good news is that outlet is virtually guaranteed to be on a dedicated circuit, and could most likely be changed to a 6-30 outlet in minutes. A new breaker(assuming there's space in the panel, or it could be made), two pieces of red electrical tape for the white(neutral) wire, and a new outlet is all that's needed.

100% correct. An electrician could easily convert this to a 240v outlet.