High Power Wall Connector

High Power Wall Connector

Are there installation and product specs on the "High Power Wall Connector" offered by Tesla for $1200? What type of service does it require? 20Amp, 30Amp, other?

How does it compare to the: Schneider Electric EVlink 30A Level 2 Electric Vehicle Charging Station offered through Home Depot for $799?

or the GE WattStation Wall Mount offered through for $1100?

Teoatawki | 22 December 2011

I don't see why you would want to buy either the EVlink or WattStation. It looks like they're basically equivalent (from a charging perspective): 240v 30 amp units with J1772 connectors. So you would still need to use the cable and J1772 adapter that comes with the car to charge. Unless you want the other bells and whistles the units provide, you might as well install a $7.50 240v 30 amp dryer outlet and plug into that. This level of charging only requires the single charger.

As for the Tesla unit: Cable hanging on wall plugs directly into your car. Can support the charging rate of dual onboard chargers, so 80amps and should require 100amp circuit. I would expect, but don't actually know if the unit can be configured to limit itself for a 30amp or 50amp circuit.

XrstalLens | 23 December 2011

The advantage of the High Power Wall Connector is that it can supply the car enough power to utilize the twin charger option. As @Teoatawki says, this requires a minimum 40 amp and maximum 80 amp service. The car itself has the charger(s) and the connector is just that - a connector. I would presume you either tell the car what type of service you're connecting it to or it obtains that information from the charging connector through the data connection that exists as part of the cable. It would limit itself to whatever service is provided based on this information. So, if you can only give it 40 amp service then I'm sure you could do that - but don't buy the twin charger option in that case!

I don't know why it's $1200, though. I suspect that it has some electronics in it to communicate with the car even though it's just a "connector" and not a charger.

Keep in mind that your charging time is directly related to how much power is provided by your service. A 20 amp service will take twice as long as a 40 amp, which will take twice as long as an 80 amp, even if all three of them are using the High Power Connector.

Teoatawki | 23 December 2011

Thanks, Lyle!

As to $1200, what you said plus... STYLE! So much prettier than the dryer outlet and a hook.

David M. | 23 December 2011

Don't forget, the max charge is 80% of the rating. So you need at least a 90A circuit for max charge with the twin chargers. That's a lot for a home. Single or twin, you can still easily charge the 300mi battery overnight (from empty). Either way you can still take advantage of Teslas superchargers (except for 160mi battery). If you are taking a road trip in the next few years, the max current you'll likely find is a 30A Level 2 charging station, unless you find an RV park with 50A charging. Either way you wouldn't need the twin charger.

XrstalLens | 23 December 2011

Tesla makes a big deal about the $7500 tax credit for the car purchase, but it turns out you may be able to get tax credit and/or other assistance for the cost of the charger and installation. There is currently a tax credit up to $1000 for a charger but it expires at the end of 2011. Apparently they're trying to extend it but I haven't heard if they have or not. Some states have have incentives as well.

That might make the price a little more palatable.

jbunn | 26 December 2011

Lyle, I thought about that deadline as well. The tesla though has the charger on board the auto. All you really need is the outlet in the garage.

XrstalLens | 26 December 2011

True, but I think the installation of the outlet would still qualify for the installation credit. And if you chose to go with the High Power Wall Connector the credit could be applied to that as well.

The main disadvantage I can think of with just going with the outlet is that you'll have to unplug the cord from the wall outlet and store it in the car if you expect to charge away from home (not at a supercharger). If, by habit, you just unplug the cable and hang it on the wall then you're toast because you will have no cable to charge with. With the high power connector you can always leave the other charging cable in the car.

Buying a 2nd charging cable is probably cheaper than the high power connector, though.

Brant | 26 December 2011

NEMA 14-50 plug (dryer/RV) will get you 40amp service (~30mile/hr). This is the best you can do at home with one onboard charger. 300mile battery is charged from empty to full in under 10 hrs. Plug is cheap, cable costs a bit. Had mine installed for $200

Tesla HPC can deliver 80amp service (~60mile/hr) but you need to get the optional onboard charger to utilize this ( and 100amp service to the garage). I don't know of any plug designed to handle this amount of amps so there is your $1200. 300mile battery is charged from empty to full in under 5 hrs

Teoatawki | 26 December 2011

Buying a 2nd charging cable is probably cheaper than the high power connector, though.

Lyle- Not necessarily. The "universal" connector in the store for the roadster is $1500 (includes 50amp RV style adapter) plus $100 for each additional adapter. Of course the roadster high power connector is $1950. So, who knows?

I'm leaning toward the high power connector myself, because not having the universal charging cable in the car even when my planned outing that day is only 10 or 20 miles gives me anxiety. Maybe I'll get comfortable as I gain experience.

If the extra charging cable turns out to be significantly cheaper even after tax rebate (assuming it is extended) I'll just install an outlet and a hook.

XrstalLens | 26 December 2011

I'm leaning toward the high power connector myself... (etc.)

@Teoatawki - you and I are on exactly the same page in this regard...

jbunn | 27 December 2011


You can find aftermarket cables on the internet for much, much cheaper already. The the s comes with adapters already. I do residential electrical work, but I probably wont even run 220 the five feet fom the service panel. just dont need it. My car sits 2/3 of the time in the drive. I drive 70 miles 3 days per week. Figure thats plenty of time. And the wife can take it the other two days and she has L2 at work. And I get her convertable...

Really, your car has to sit at least 8 hours, because you need to recharge too... charging you car faster than you can drive off it is nice, but ultimatly useless.

gagliardilou | 30 December 2011

I feel with the 300 mile pack, you need twin chargers and charge at 62 miles per hour. 9 to 10 hours is too long to charge but 4 to 5 works. Although admittedly, the car will not be totally deplated everyday - probably not even close. I heard it will cost $10.00 a day to charge the car but am assuming that is from empty.

gagliardilou | 30 December 2011

Sorry, thats "depleted" everyday

Mycroft | 30 December 2011

lgagiardi, I'm buying the HPC for several reasons:

1. While I wouldn't exactly call it "Art" as Tesla does, it is very nice looking. And it will match the Model S in my garage very nicely.

2. I can keep the travel charger in the car all the time and I think the HPC plug and cable will be slightly more convenient to use on a daily basis than having the travel charger plugged into a 50A receptacle.

3. I can easily have to travel over 100 miles in a day. So it would be nice, if the wife and I want to go on a weekend excursion starting Friday evening, to do a fast charge with the HPC before leaving.

The amount it costs to charge the car from scratch depends entirely on the cost of electricity in your area. For my area, it's 6.5 cents per kWh, so it should cost around five or six bucks to charge up at the most.

Robert.Boston | 30 December 2011

Make sure you sign up for your utility's real-time / time-of-use pricing (In the Chicago area, ComEd's Rate BESH This will let you save even more by using cheap overnight power (and only being charged at the lower rate).

Brian H | 30 December 2011

It's described as "alien art", so you have to have been born far, far away to fully appreciate it.


David M. | 15 January 2012

Get this - I'm cleaning up my garage and lo and behold I find a 240V, 20A outlet that the builder installed ten years ago. It's a NEMA 6-20. I estimate that it can fully charge the Model S (300), from empty in about 17 hrs. Usually my car will sit for about 14 hrs overnight. Should I even bother installing a 240V, 50A, NEMA 14-50?

EdG | 15 January 2012

@David M.
You have to assume most of the time you won't be flat empty. And the small number of times you are, you probably won't be needing a totally full charge the next day.

David M. | 15 January 2012

Thanks EdG. I was thinking that way. However, the 14-50 plug comes standard with the car. Tesla has been pricing the other adapters at $100 ea. For $250, I can have an electrician install a 240V, 50A outlet. Hmmm.

If Tesla continues to offer an adapter package with 9 adapters, I might get that anyway for road trips.

Douglas3 | 15 January 2012

You can just wire up a NEMA 14-50 to 6-20 adapter yourself using a few parts from a hardware store. You can tell the car to draw less current, so it won't blow the fuse (or melt anything).

Also the Roadster (and I'm sure the Model S) can be told to draw only 16A instead of 40A, and it will remember that based on the GPS location. So whenever it returns to the same location it will use the same charging current as last time. Pretty slick, huh?

Soflauthor | 16 January 2012

I think this has been covered in earlier threads, but I can't seem to find it (better search is needed): Why is it advisable (or is it?) to charge the battery every night? Let's say you own a 300 mile battery and drive, say, 30 - 40 miles per day, on average. What's the down side of going 2 , 3 or even 4 days to about half charge and then recharging overnight in your garage? Is there demonstrable degradation of the battery in taking that approach?

stephen.kamichik | 16 January 2012

TM says to charge every night or when convenient.

brianman | 16 January 2012
Soflauthor | 16 January 2012

@brianman: Thx for the pointer. Just what I was looking for.

The OP on the TMC thread adds a comment that is not addressed in the Tesla letter on the subject:

I read a study about these laptop batteries that quoted the loss of capacity per year when kept at certain temperatures and charge levels.

When kept fully charged at 40 degrees celcius then the loss in capacity approaches 15% to 20% per year.

When kept closer to 50% SOC and at 25 degrees celcius then the loss in capacity is about 4% per year.

When kept at 50% SOC and 10 degrees celcius then the loss in capacity is about 2% per year.

If 50% SOC at 25 degrees celcius with a loss in capacity is about 4% per year is accurate, then it would seem that it might be advisable to not top-off the battery each night (under the circumstances I noted in my earlier post). Hopefully the Model S owner's manual will address this and amend the recommendation that was made for the Roadster, or I may be misinterpreting things.

Mycroft | 16 January 2012

From the bottom of the Model S "Facts" page:

"Battery lifetime is affected by two things: age and the energy it delivers over the years. The Tesla battery is optimized for nightly charging: such topping off enhances the longevity of your battery."

Discoducky | 16 January 2012

I highly doubt TM will not the very best job at managing the lifespan of the batteries. To compare how computers deal with batteries is not apples to apples. For instance, most laptop battery packs do not have a way to tell the BIOS their temperature only how much charge they need (like trickle or full charge), or if a cell is bad (maybe, this was a big feature add back in the day and some manufacturers gave it a marketing name like "Battery Learning"). Laptop makers will put a thermistor (temperature diode) close to the battery to get an idea of temperature. But it's hit and miss at best.

If I had to guess, I bet TM uses several different ways to guess the temperature of different parts of the pack (looking at different zones and trends) to understand how to discharge and charge those zones. As well as putting just the right amount of charge on each zone to ensure no battery cell gets too much while still retaining the range requirements. Also, with liquid cooling they can do a much better job at controlling spikes in temperatures.

EdG | 16 January 2012

Don't forget that most laptop manufacturers make money selling replacement batteries, while they don't have any downside for not optimizing battery life. At least not yet.

stephen.kamichik | 16 January 2012

TM also states that they use AUTOMOTIVE GRADE batteries, whatever that means.

EdG | 16 January 2012

I think that's what grade someone in high school would be expected to get if looking for a job in the field of auto mechanics. "Laptop grade" would be for those going into computer science.

Teoatawki | 16 January 2012

Keep in mind that plugging your car in every night does not charge the battery pack to 100%. The car charges to a level that supports optimal battery life. It only charges to 100% in range mode. You should only do this when you anticipate an immediate need for the additional battery capacity range mode makes available. Always charging in range mode would have an adverse effect on battery pack life.

David M. | 16 January 2012

Remember my post?
" lo and behold I find a 240V, 20A outlet that the builder installed ten years ago. It's a NEMA 6-20".

Well, after taking a closer look at the receptacle and examining the panel box, apparently, it's only a NEMA 5-20 (120V), crap!

I guess I'll be having the electrician install the NEMA 14-50 after all. I knew I should have taken that electrical engineering course.

Brian H | 16 January 2012

"EdG | January 16, 2012 new

I think that's what grade someone in high school would be expected to get if looking for a job in the field of auto mechanics. "Laptop grade" would be for those going into computer science."

Do people often glance admiringly at your hiney and comment on its intelligence?


stephen.kamichik | 16 January 2012

I thought "Laptop grade" is my beautiful secretary sitting on my lap.