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Is the dual charger option useful and worth getting?

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lupacexi

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Jul 4, 2018
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I'm not sure if I should get the Duel Charger ($2000 including installation) put into my Model S given how I currently recharge and use the car.

I mainly recharge using my installed 240v wall plug in the garage. I rarely charge at public charging places. On occasion, when I go out of town, I do use the superchargers along the way (although I hear that the Duel Chargers do not affect the charging times of the supercharger).

I guess the ultimate question is where under what circumstances would the Duel Charger be useful, and worth getting?

Any info on this would be greatly appreciated.

Thanks
 
The car charger has nothing to do with Supercharging. Period. That’s DC charging.

Having high powered car chargers (AC chargers) are useful for traveling if you stay somewhere with a high powered Destination Charger and you want to recharge more quickly because someone may be waiting for the HPWC.

But the first question is what car are we talking s out? An older one? A CPO? No new Tesla has an option for a larger charger. They come with a specific charger (S and X 48 amps, 100 pack 72, the 3 is a little smaller)

Older S’s had a single 40 amp charger and the option of a second 40. The option may be still be available after sales.
 
When I ordered our first Model S (2012 S P85), that was our first EV, and because of "range anxiety" the S was configured with the dual chargers (80A), along with a full set of charging adapters. Though at that time, there wasn't a supercharger network or destination charger network, so taking road trips were an adventure - trying to find any charging on the way and at destinations...

Our Gen 1 HPWC is on a 100A circuit, so the S P85 could get a full 80A charge at home - about 60 miles of range added per hour.

And... In 5 years of having the S P85, we used the faster charging at home only once. And that was in the early days when I did my daily work commute during the day and then needed to get a quick full charge before heading out on a road trip. Because there weren't any superchargers, I had to stretch the charge long enough to reach the J1772 charger at the destination hotel. Once the supercharger network was deployed - never needed to use the fast charging again.

When we ordered our S 100D last year, 48A charging was standard. We elected not to pay extra to upgrade the charger to 72A. [As it turns out, our S 100D has the 72A charger on board, and Tesla wants us to spend $1900 to flip a software switch.] We have almost 25K miles on it already, and haven't needed to charge faster than 48A at home.

Since the S 100D arrived, we moved our S P85 over to a 14-50 adapter, getting only 40A of charging - and that has been enough to get it fully recharged overnight.

Two weeks ago, we replaced the P85 with an X 100D (with a 72A charger), and it's now charging on the 14-50 outlet using a Gen 2 UMC, getting only 32A of charge - and that's been enough to get a full charge overnight.

It's highly unlikely the OP would benefit from adding the secondary 40A charger, unless the OP does a lot of local driving each day and needs to get a quick, full, charge mid-day. On road trips, the superchargers should fulfill the fast charging needs - and for overnight charging on destination chargers, a 40A charger is probably good enough (especially since many destination chargers don't support more than 40A charging anyway).
 
...I guess the ultimate question is where under what circumstances would the Duel Charger be useful, and worth getting?...

Like @boaterva explained above:

Home charging using the onboard charger in your car.

Fast DC chargers such as Superchargers, CHAdeMO, CCS... do not use your built-in charger in your car so Fast DC doesn't care whether you have zero, 1, 2 or more onboard chargers in your car at all. (The chargers are installed outside of your car and non-Tesla brands have their charging cables connecting to a huge cabinet

2011-nissan-leaf_100337270_m.jpg



while Tesla brand hides those chargers away and drivers only see a nice artistic work connecting to a charging cable.

If you have enough battery to go to a Fast DC or Supercharger, you can skip traditional onboard chargers.

So, higher charger capability in your car is not useful for Fast DC chargers above.

It's useful for home and destination chargers. Actually, they are not "chargers" because they use your car's onboard chargers and that's why they look much smaller than visible non-Tesla Fast DC chargers above. They are "connectors" but it's too weird for a layperson to say that so most just give up and just call them "chargers".


If a home or destination connector is connected to 240V and 30A circuit then, it's a waste for dual chargers because even a single charge can handle 50A circuit.

To be useful for your dual chargers in your car, your home or destination power connectors must provide a breaker with 240V and 100A.

It is useful to have a dual charger system because it's twice faster than a single one in this case.

If you have exhausted your battery by the time you get home and you need to change clothes and get a quick bite while the car charge for 30 minutes or you have to wait for a long 1 hour depending dual or single charging system.
 
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I have dual chargers on my S and have used it (I.e. charged it on a charging station offering more than 40A)... drumroll please... exactly once since 2014. Only scenario where it might be useful is if you regularly drive over 200 miles a day, get home late at night (e.g. midnight) and need to leave early in the morning (e.g. 4am), and you already have a wall connector with 80A service. Or if you drive a lot (Uber, etc.,), need to top off quickly during the day, and can’t or don’t want to supercharge.
 
I have the single charger, and I can't think of a single time where a dual charger would have helpful. Single is fine for at home for me. Most destination chargers (in my experience) don't go above 40A anyway, so that's of little help.

I would suggest holding off on that upgrade and waiting to see if you'll find it useful. (I bet you won't.)
 
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Last weekend we were at a B&B that had an 80 Amp HPWC. For the first time, I charged st 72 Amps all the way (just to be sure my 72 Amp charger actually worked). This is the main time it’s useful, when you don’t want to hog a destination charger and it is capable of more than 40 amps (for older cars) or 48 amps (newer cars with the smaller charger). The other case, as was mentioned, is you come home with a low SoC and need to head out immediate AND you have an HPWC that can also charge quickly (72 amp).

So, it’s all up to you: what cases do you feel do you need to be ready for. New cars don’t have the choice, as they come with 48 or 72 for S and X, etc.

Only the older S has the option to add the second charger at a lot of cost. :D

Edit; on the Destination Chargers, many new setups are the Gen 2, and they have three or four on one 100 amp circuit. So, if there are more than one car there, you will be sharing the power anyway. Another case for not getting the worth of the extra chargers. But most people won’t have a choice anyway.
 
i have a P85 with a single charger and have never had an issue charging overnight with a 30A dryer plug in the mud room getting a whopping 22 miles of range per hour of charge. it took roughly 9.5 hours to go from 7% to 90% last night.
we're moving later this month to a home with 200 amp service, so i'll have a 14-50 installed in the garage and maybe get 40 amps because of my single charger, and that'll be fine for our needs.
 
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We have older build Model S (see sig) and paid extra $$ for dual chargers. They have been rarely used, and I would not miss it if the extra charger was not there. Unless you are doing a lot of local driving (like a realtor or the like) and need to top off in an hour or so, I would skip them.
 
I agree with what pretty much everyone else has said, had a single charger car since 2014, never wished for the dual chargers. Have a 2017 P100D now too with the 72A charging and I've never used it, nor plan too.

Only reason I would upgrade is if you had a very specific use case in mind. Something like a frequent road trip where you want to leave right after a long commute. Otherwise save your money.
 
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I also have to throw my hat in the "dual chargers are likely not needed" category.

When I originally bought my S in early 2013 I, like many here, opted for dual chargers and bought a variety of plug adapters. At that time the charging frontier was much more of the WIld West than it is today.

I installed my HPWC on an available 50A circuit, with the intent of upgrading to a 100A circuit when I figured out if I was going to do solar, get an EV charging plan with second meter, etc... The latter never happened, and I've used 40A charging at home ever since. I used a 70A destination charger once.

A couple of years ago my primary charger failed (actually turned out to be blown fuse, but I didn't know that at the time), and I reconfigured my car for single charger use.

With the rapid rollout of the Supercharger network, 40A has served me just fine. If you live or travel off the beaten path and need to rely on destination/interim chargers you know are >40A then you might consider it, otherwise I think you can save a few $$$.
 
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I'm in the minority here, but I for one am quite happy I decided to add the second charger (so 80A total now) on our S85.
I agree with above: mostly, it is unused: charging at home is enough for our daily need (and some more), and while traveling, Superchargers are the best and easiest option.
I do appreciate it at our destination on vacation/business trip, where there is no possibility to charge at all or charge fast enough for the next morning. Then using a nearby public charger or Tesla DeC to its full potential (AC), which is 22kW/80A, provides over a nice diner/shopping moment (1h30 to 2h) an almost full battery, so mostly enough to be able to drive around, or reach the next supercharger if going further.

But agreed also it is an expensive add-on, providing just some more comfort.
 
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This is a very interesting question, and is one I have considered before and talked with my wife about. First off, why I don’t have it yet:

Before and after I ordered, Tesla offered the option of selecting the dual charger in configuring the order, and I would have considered adding it. But for a short time period, back in January 2014, Tesla did not offer it as a separate option. They ONLY offered a bundled option of the second charger & the wall connector (which I didn’t need) for $3,800!!! That was awfully high for something I would rarely use plus something I would never use.

I don’t generally see any need for it at home, especially if you do have a Supercharger in your city for some rare weird use case where you need a quick refill for some reason. And for destinations, it’s usually not very necessary.

The use case I do have exists very rarely, but I do have it. I live in Boise, and if you look at the Supercharger map, it is right next to a huge hole in the Supercharger placement to the West/South, with a couple of major routes that are too long for a full charge of the car. They happen to be US highways, though, not interstates, so Tesla hasn’t done anything with them. Helpful Tesla owners have donated wall connectors to businesses, where they are installed on high power circuits. So they make these routes fairly passable with a high amp refill in between the Superchargers at either end. But if you don’t have the high amp chargers, these stops are near 2 to 3+ hours, which is a little rough along your trip.

But really, we’re in 2018, and Tesla is continuing to add more Superchargers, so these odd gaps will get filled at some point in the next few years. And even so, for a route that we use maybe once or twice a year, I can rent a car or take our other car for the next couple of years until Supercharger coverage makes it moot.
[As it turns out, our S 100D has the 72A charger on board, and Tesla wants us to spend $1900 to flip a software switch.]
I don't think that is correct. They were going back and forth a bit with the Model X, and builds at different time frames had the actual 48A one or the 72 software limited to 48A, but by the time they rolled the updates into the refreshed Model S, they weren't doing the software limited chargers anymore, so all Model S cars require a hardware swap to go from the 48 to the 72. See this comment showing the description of this and the date ranges involved.
Did anyone upgrade from 48 to 72 Amps?
 
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One use case that everyone's missed - if you are on a TOU rate plan with a narrow cheap nighttime window, dual/hi amperage chargers could save money on your electric bill if it allows you to do all your charging during that window vs spilling into a more expensive period. However, it's unlikely you'd ever recoup the cost of the faster charging option.

My CPO came with dual charging. I've used 80A chargers several times while parked for meetings, dinners, etc. that include a 150-250 mile round trip. Tesla has since opened or announced superchargers near or on the way to these sites, so I wouldn't pay extra for it on my next car.
 
I don't think that is correct. They were going back and forth a bit with the Model X, and builds at different time frames had the actual 48A one or the 72 software limited to 48A, but by the time they rolled the updates into the refreshed Model S, they weren't doing the software limited chargers anymore, so all Model S cars require a hardware swap to go from the 48 to the 72. See this comment showing the description of this and the date ranges involved.
Did anyone upgrade from 48 to 72 Amps?

I called Tesla and they verified our S contains the 72A hardware and that upgrading from 48A to 72A would only require a software change.

Though unless Tesla lowers the price of doing the update - unlikely we can justify it, since 48A charging should be fast enough for our home and road charging.

What's unfortunate about the 48A to 72A upgrade - shortly after we received our S last year, Tesla made the 72A charger standard for the 100 battery packs - at no additional charge...
 
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I like dual chargers and have purchased it 2 out of 3 times. That's my bias. That said...

The important thing for home charging is to get to at least 14-50 (240V @ 40A, or slightly less accounting for wiring/losses) ASAP. You definitely feel range anxiety (at least I did and do) limited to 120V @ 12A (standard household outlet).