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New Model S owner charging primer (US)

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ChadS

Last tank of gas: March 2009
Jul 16, 2009
3,559
3,068
Redmond, WA
Charging SourceTechnical DetailsMax powerRequired to use it
Household outlet
household.jpg
NEMA 5-15 outlet
110V, 15A
Must draw 12A or less (you can only draw 80% of rated outlet capacity for a continuous load)

Note that there is a similar NEMA 5-20 110V 20A outlet that you can plug in to, but Tesla does not allow you to pull more than 12A unless you buy a separate adapter for it so they can be sure they are on a 20A circuit.
1.3kW (up to 3mph)5-15 adapter is included with the Model S Mobile Connector

5-20 adapter is available from Tesla.
J1772 "Charging station"
j1772.jpg
J1772 EVSE

An EVSE is similar to an outlet, but safer.

240V. Typically 30A delivered on a 40A breaker. (Spec allows up to 80A delivered on a 100A breaker; that makes it equivalent to a Tesla Model S HPWC, below).

Any plug-in vehicle in the US since 2010 should be able to use these. The Tesla Model S can, with an included adapter. The Tesla Roadster, released before the standard was finalized, requires a separate $650 adapter.
7.2kW (up to 22mph) assuming 30A. But a few are at 19.2kW like an HPWC; so see below for specs on that.Adapter is included with Model S. J1772 plugs into the adapter, which plugs in to the car.
Campground 50A outlet
campground.jpg
NEMA 14-50 outlet
240V, 50A
Must draw 40A or less (you can only draw 80% of rated outlet capacity for a continuous load)

Big RVs use these at RV parks to run air conditioning and other electrical loads in the RV. Do not confuse this with a 30A campground outlet, which is only 110V!
9.6kW (up to 29mph)Adapter is generally included with the Model S Mobile Connector; but if you have a different 240V outlet in your garage to charge the car, you may get that adapter instead, and then you would have to buy this one.
Tesla Roadster HPC
hpc.jpg
Tesla Roadster EVSE

An EVSE is similar to an outlet, but safer.

240V 90A breaker; 70A delivered (if 90A is not available, it can be installed at a lower level)

The Tesla Roadster is the only car that can use these EVSEs (except a Model S with an appropriate adapter from Tesla).
16.8kW (up to 50mph)A $650 adapter from Tesla. HPC plugs in to the adapter, which plugs in to the car. You must also have Twin Chargers to use more than 10kW.
Tesla Model S HPWC
hpwc.png
Tesla Model S EVSE

An EVSE is similar to an outlet, but safer.

240V 100A breaker; 80A delivered (if 100A is not available, it can be installed at a lower level)

The Tesla Model S is the only car that can use these EVSEs.
19.2kW (up to 58mph)Plugs directly in to the Model S. But you must have Twin Chargers to be able to use more than 10kW.
CHAdeMO Charger
chademo.jpg
CHAdeMO standard DC Charger
Can be up to 65kW, but most installations are at 48kW

This is a real charger, not just a power supply. It talks more directly to the battery than an EVSE. But the car still has to talk the protocol.

The Nissan Leaf and the Mitsubishi i are currently the only cars in the US that can use these chargers.
48kW (up to 144mph)An adapter from Tesla. They are “working” on one for $1,000; availability probably very late 2013. Will also require the Supercharging option (which is standard with 85kWh, optional on the 60kWh).
Tesla Supercharger
supercharger.jpg
Tesla’s proprietary DC Charger

This is a real charger, not just a power supply. It talks more directly to the battery than an EVSE.

The Tesla Model S is the only car that can use these chargers.
120kW (up to 300mph)Plugs directly in to the Model S, if the car is Supercharge capable. Standard on 85kWh models, optional on 60kWh models.
 
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  • Informative
Reactions: rafacq
Here is a picture of the Mobile Connector that is included with every Model S. It includes adapters for household outlets (110V), and one 240V adapter - by default, shown here, the campground 50A adapter.

At some point Tesla will have other 240V adapters in stock for sale; I will have to update this table then...

mc.jpg


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Time for some boring caveats! When I list the power delivered (and the number of miles of range you gain per hour of charging at that power level), the number I am listing is a maximum. There are a great many reasons you could get less. Here are a few of them:



  • It could be lower voltage. In fact many commercial sites at nominally 208V instead of 240V, and may sag to 200V or even lower. That can knock off 20%.
  • It could be lower current; just because (say) an EVSE can handle 80A doesn’t mean it was installed on a circuit of that size.
  • If it is really hot or cold, your car may be diverting a lot of power to manage the battery temperature. This matters more on slower sources; in fact in extreme conditions, a 110V outlet may not charge your car at all.
  • To protect the battery (generally when really hot, or nearly full) the amperage may be dialed down. Charging from 20-80% with a fast source may be faster than charging from 90-100%.
  • If you are sitting in the car running the HVAC while charging, you’re using part of the power and slowing down charging. At full blast HVAC, a low-voltage J1772 (about 6kW) might spend almost all its power on you instead of the battery
  • Your car has to be able to handle the power! For AC charging (outlets and EVSEs), the usual limit is how much power your built-in chargers can take. Tesla by default has a 10kW charger; good enough for 110V, most J1772s, and a 14-50. With Tesla’s $1,500 “Twin Charger” option, the car can handle 20kW, so now you can also handle everything a fully-spec’d J1772, HPC or HPWC can deliver. DC chargers are faster than that, but for those the charging is done in the charger instead of in your car, so whether you have single or twin chargers doesn’t matter. But to do a quick DC charge, you must have Tesla’s “Supercharger” option, which is included with the 85kWh pack and a $2k option on the 60kWh pack. A 40kWh Model S can not use DC chargers.
 
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The only thing you have to note is that many of those options will be 208V instead of 240V, and charging power varies with voltage (since power = volts x amps).

Many industrial / commercial installations, condo / apartment buildings, etc., are based on a 3-phase 208Y/120 system. The St. Louis Science Center, for example, charges at 208V, 30A. The St. Louis airport chargers have such a long run in their wiring that voltage drop delivers only 200V at 16A. As a result, J1772 isn't always 240V. The same will apply to 14-50's, 6-50's, J1772's, HPWC's, HPC's, etc.

You can also have higher charging power with higher voltage. For example, at my home, you get 245V under 40A load on my 14-50, which is 9.8 kW. The charger voltage is spec'ed from 80-265V. At 265V/40A you'd actually charge at 10.6 kW - although I don't know if the car would reject/limit that to 10k max.

Another point to make is that you can't say that it's typically a 30A delivery on a 40A breaker -- it all depends upon the EVSE nameplate rating as to what breaker is permitted.
 
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Thanks, Flasher. I did note the potential (heh) for varying voltage and its effects on power in the "boring caveats" above. I fixed the typo on the NEMA name for the welder outlet (should be 6-50 as you note). I stand by the "typically 30A delivery on a 40A breaker" comment, though. You are of course correct that any EVSE could have different specs, but almost all non-Tesla installations are 30A on 40A, and "typically" covers the few exceptions. If you pull in to a public EVSE and charge, I'll bet chances are 95% or higher that you'll get 30A delivered on a 40A circuit.

-------------------------

Differences between outlets, EVSEs, and chargers (optional reading for the curious):

Outlets
There are many, many types of outlets. See HERE. Fortunately you don’t have to worry about all of them. The ones Tesla supports are listed HERE (click “adapter guide” to see the list). I’ll call out some of the more familiar of Tesla’s supported outlets:

  • “Ordinary” 110V household outlets (aka NEMA 5-15); your Model S comes with an adapter for that. SAMPLE.
  • The most common 240V outlet for charging is a NEMA 14-50 (aka “campground”) outlet; you find those at campgrounds, and some hotels and restaurants, fire, police and ranger stations, fairgrounds, appliance stores, and in some garages and workshops. Many people install such an outlet at home for charging; in fact Tesla recommends it if you don’t buy their High Power Wall Connector (which is an EVSE; see below). It is far cheaper than installing an EVSE (a few hundred to put one in a garage, versus over $1 - 2k for an EVSE). SAMPLE. Your Model S will come with an adapter for this unless you tell Tesla before delivery that you’d prefer one of their other 240V adapters instead.
  • Many early EV drivers have also charged from a NEMA 10-30, commonly used for “older” clothes dryers. SAMPLE. Newer dryers use NEMA 14-30.
I have done almost all of my charging from a 14-50 “campground” outlet. I have used a 10-30 “dryer” outlet five times. I have never used 110V charging or any other outlet.
So with the included Tesla plugs, you can plug in to:

  • 5-15 “Ordinary Household” 110V outlets, and
  • 14-50 “Campground” 240V outlets
  • You can also use 6-50 “welder”, 10-30 “old dryer” or 14-30 “new dryer” outlets if you buy another plug from Tesla
EVSEs
EVSE is a clumsy acronym that stands for “Electric Vehicle Supply Equipment”. It is very similar to an outlet, but it contains extra circuitry to protect you. If you plug a cord into an outlet and accidentally touch the prongs, you can get electrocuted. But an EVSE doesn’t put current out over the pins until it detects that it is plugged in to a car. An EVSE is not the same as a charger, but often is called one – it looks and acts the same, it’s just a matter of where the charging smarts are. An EVSE relies on the charger being in the car. Your Model S has one or two (“twin”) AC chargers built in; one charger lets you pull up to 10kW, twin chargers let you pull up to 20kW.

Of course, if it’s in your garage, the outlet end normally stays plugged in, and you only plug the car in – and the connector between them has the same protection built in. So I think EVSEs are oversold, and cheaper outlets work just fine for most people.

Almost all EVSEs use a “J1772” connector SAMPLE. This is the standard for 240V AC vehicle charging, sometimes called a “J plug”. However, this standard was not adopted until 2010; so in California you can find old EVSEs that use different interfaces – their numbers are dwindling as they get upgraded.

Almost all EVSEs (at least outside of CA, though this is becoming more and more true even there) that don’t use J1772 belong to Tesla. The Roadster was released before 2010, so they had to invent their own EVSE: the HPC (SAMPLE). It operates just like a J1772 EVSE, just the plug is different – it uses a plug found only on the Roadster. Then for the Model S, they wanted to do DC fast charging (see “Chargers” below) using the same connector as their AC charging, so they created (sigh) yet another plug. This is the “Tesla connector” (SAMPLE) that is on your Model S. So the Model S is the only plug-in vehicle being sold now that doesn’t have a J plug. It does include an adapter, however, so you can use J1772 EVSEs. And Tesla has created their own EVSE with a Tesla connector: the HPWC, or High Power Wall Connector (SAMPLE).
Ignoring the old CA EVSEs that seem to be disappearing, the only EVSEs you might run in to are:

    • J1772 EVSEs. These are by far the most common. Your Model S includes an adapter to use them.
    • Roadster HPCs. Some have already been converted to J-plugs. Some, I suspect, may someday be converted to Tesla plugs for the Model S (only after Tesla offers an upgrade to Roadster owners). To use the rest (like the ones in Ferndale, Ellensburg, and Centralia WA), you can buy an HPC adapter for your Model S for $650 from Tesla. They are in very limited supply right now, and they are currently only selling them to people that own both a Roadster and a Model S.
    • Tesla HPWCs. None of these are out in public; for now these only exist in the garages of owners. This will plug directly into your Model S.

Chargers
Chargers are more than just outlets, or even smart outlets that try to not kill you. They know what they’re doing. They know they are sending power to your batteries, and they can manage the power delivery to get your battery full in the best manner – fast, but without frying the batteries. You always need a charger; but when you plug in to an outlet or EVSE, you use the AC charger built in to your car. Your Model S therefore only uses DC chargers.

Tesla’s DC Chargers are called Superchargers. They use the same Tesla plug as Tesla’s EVSE (the HPWC), so they will plug right in to your car. They are fast, free, and solar powered. It's just too bad they are not very numerous yet. They are in Southern California, and there are a couple on the East Coast between Boston and DC.

The SAE (the standards body that defined J1772 too late for Tesla) recently defined a new standard (once again, too late for Tesla) for DC charging. There are not yet any cars that use it, and no chargers yet being made, so none installed anywhere. Bummer. But if they ever do get installed, Tesla uses the same communications protocol, so you should be able to plug in to these chargers with just a simple adapter.

The Nissan Leaf and Mitsubishi i-MiEV use a TEPCO connector and the CHAdeMO communications protocol. There have been at least 5 projects installing CHAdeMO DC chargers around the nation; WA and OR have the most. Great! Except...not just the plug, but also the protocol is different. Creating an adapter is difficult and expensive because it requires a bunch of electronics. Tesla is working on it, but has not suggested a date or price.
So that makes 3 types of DC chargers, but you can’t use any of them yet unless you happen to live near a Supercharger. That’s really sad, because DC chargers are a lot faster than AC outlets or EVSEs.
 
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Most excellent post!

- - - Updated - - -

One of the questions I have with NEMA 14-50 outlet 240V, 50A is what happens if the voltage or amps is less than 240V and or 50A. If I plug my MS into a NEMA 14-50 that is not producing 240V at 50 A, what harm can occur? What if I plug in at night and the 14-50 drops to 240V and 30 amps?????
 
One of the questions I have with NEMA 14-50 outlet 240V, 50A is what happens if the voltage or amps is less than 240V and or 50A. If I plug my MS into a NEMA 14-50 that is not producing 240V at 50 A, what harm can occur? What if I plug in at night and the 14-50 drops to 240V and 30 amps?????

The Model S charger is a switching power supply that can use any voltage between 80 and 265V, according to their specs. The car will simply charge at a slower rate (since power = volts x amps).

Current (amps) is a bit different... you really won't see current "drop" unless something is overloading another component in the system, in which case you'll run into heat problems and/or voltage problems usually first (or you trip a protection device, in which case all goes to 0).
 
Alright. Voltage variation no big deal. Variation in amperage (drop??) is a bigger deal?

Thanks for walking this electrical noob through the Mr. Wizard school of understanding electricity.

You don't have to worry about a "variation in amperage". Without going into too much of a detailed course in electricity, here are the basics: the current is more of a load-defined characteristic, while voltage is a supply-defined characteristic, and the resistance of a circuit balances it all out (Ohm's law). The car is engineered to draw a specific current. If that current is available, the resistance of the load remains constant, and the circuit stays well-balanced. If that current is unavailable due to an overload somewhere, the resistance of that overloaded portion of the circuit (wire, transformer, generator, etc.) will go up. By ohm's law, this will result in a voltage drop (and a lot of heat at that overload point!) By then, hopefully some kind of current overprotection device (a/k/a "circuit breaker") has disconnected the circuit completely.

As a result, you won't really "see" that current is available, except if a circuit breaker trips (indicating overload) or heat/fire. Long before that, you'll see voltage impacted first.
 
Alright. Voltage variation no big deal. Variation in amperage (drop??) is a bigger deal?


Thanks for walking this electrical noob through the Mr. Wizard school of understanding electricity.

As long as you're not going over the amperage of your power supply, 40 amps in the case of Nema 14-50, there isn't much reason to pay attention to amperage. Voltage is more interesting because it gives you some idea of where you're getting your power from, how long of a run it is from the transformer and how thick of wire is being used.
 
... The SAE (the standards body that defined J1772 too late for Tesla) recently defined a new standard (once again, too late for Tesla) for DC charging. There are not yet any cars that use it, and no chargers yet being made, so none installed anywhere. Bummer. But if they ever do get installed, Tesla uses the same communications protocol, so you should be able to plug in to these chargers with just a simple adapter. ...
If (when?) we do see an adapter, it will probably look pretty ugly.
j1772-dccombo-03-vga.jpg
 
Great write up ChadS.

In regard to the quote below, the J1772 connector is "finger resistant," but I think EVSEs provide most of the protection when plugging in your car. It is best to have the breaker off when plugging and unplugging a 14-50. The ESVE keeps the J plug or Tesla plug deenergized.

"Of course, if it’s in your garage, the outlet end normally stays plugged in, and you only plug the car in – and the connector between them has the same protection built in. So I think EVSEs are oversold, and cheaper outlets work just fine for most people."

"And Tesla has created their own EVSE with a Tesla connector: the HPWC, or High Power Wall Connector (SAMPLE)."

In addition to the HPWC, Tesla also has a mobile EVSE for the Model S.
 
First, great post, I hope you'll summarize with the caveats you've listed below and some of the other good points presented into a nice wiki that can be updated going forward as needed. But very well done.

I would like to see the MPH (charge range/hr) numbers specify "Ideal" range and to post the "rated" range beside it. I think most of us are using rated range as the default these days and it might help eliminate a little confusion...unless it just makes it more confusing!
 
Chad, great post, thanks!

First, great post, I hope you'll summarize with the caveats you've listed below and some of the other good points presented into a nice wiki that can be updated going forward as needed. But very well done.

I would like to see the MPH (charge range/hr) numbers specify "Ideal" range and to post the "rated" range beside it. I think most of us are using rated range as the default these days and it might help eliminate a little confusion...unless it just makes it more confusing!

+1 for both the wiki idea and the addition of rated numbers. I find myself using the rated and not ideal setting exclusively.
 
... The SAE (the standards body that defined J1772 too late for Tesla) recently defined a new standard (once again, too late for Tesla) for DC charging. There are not yet any cars that use it, and no chargers yet being made, so none installed anywhere. Bummer. But if they ever do get installed, Tesla uses the same communications protocol, so you should be able to plug in to these chargers with just a simple adapter. ...


If (when?) we do see an adapter, it will probably look pretty ugly. View attachment 13818

ChadS, were you talking about the pictured "Frankenplug" (AKA "The Combo") or something new where they do DC over the normally AC pins in the smaller round J1772 plug/socket?

There is an Eaton SAE DC QC recently installed here in Belmont.
I saw a VW prototype car charging from it.
I think we expect to see Chevy Sparks with the SAE DC QC port soon too.
http://www.cartype.com/pics/10171/full/chevrolet_spark_ev_14_04.jpg
 
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Yes. It's 20 feet long, but they say the outlet should be less than 18 feet from the charge port on the driver side tail light. (Source: http://www.teslamotors.com/sites/default/files/downloads/universalmobileconnector_nema_14-50.pdf)

I prefer to keep the 20 ft cable in the car for use on the road only, and won't need a 20 ft length cable in my garage as I have the NEMA 14-50 connector installed in right across from the Model S charging port.

Would be nice if Tesla would sell a 4 ft version of this cable. Or if they don't, does anyone know a way to shorten the 20 ft cable?
 
Thanks ChadS (and FlasherZ too)

I think it's also worth understanding that other cars have onboard chargers that are much more limited than the Model S, and it's kind of a waste to have them use high power EVSE, especially if you really need it. On the way back from LA to SF last week we drove (in our Acura) the 101 and I checked out some of the old Roadster HPC that have been converted to J1772, and one was taken up by a Volt. My wife was none to keen on having to wait around for the volt to leave before we would have to spend our own 2 hours charging there, if we were driving the S. I'm thankful there are other options, like the high power EVSE at Lloyd's office in SLO with a $5/hr fee which pretty much guarantees that it will be available for us road trippers.

On-board charger capabilityVehicles
2.2kWPlug in Prius
3.3kWpre-2013 Leaf, Volt, iMIEV, Fisker, smartEV
6.6kWFocusEV, 2013 Leaf, Coda, Original Rav4EV, FitEV
7.7kWActiveE
10kW2012 Rav4EV, base Model S
12kWMiniE
16.8kWRoadster
20kWModel S with twin chargers