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Twin Charger Confusion

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I had been told by a Tesla Rep (over the phone) that the second charger kicks in at 40 amps but while speaking to a technician at a Tesla Service Center I was told that the second charger only kicks in at 80 amps and requires Tesla's High Power Wall Connector. I'm apt to believe the service tech as the phone rep was probably working off a script while the service guy worked on these cars every day.

Am I the only one who was given that 80 amp figure?
 
I had been told by a Tesla Rep (over the phone) that the second charger kicks in at 40 amps but while speaking to a technician at a Tesla Service Center I was told that the second charger only kicks in at 80 amps and requires Tesla's High Power Wall Connector. I'm apt to believe the service tech as the phone rep was probably working off a script while the service guy worked on these cars every day.

Am I the only one who was given that 80 amp figure?

Twin chargers are necessary if you want to use charging stations providing more than 40 amps but no more than 80 amps, although it need not be a HPWC (70 A stations by Clipper Creek do just fine with twin chargers). Unfortunately, Tesla is now tying purchase of an HPWC in with the option for dual chargers. Tesla is wrong for doing that, as others have posted, because most people who want dual chargers don't want or need the HPWC. There have been quite a few posts on this topic, this week in fact, so if you search (always recommended) for twin or dual chargers, you will find learn a lot. In California, you will get more use of twin chargers than in other places around the U.S., but if I was being forced to buy a HPWC, that is a lot of extra expense that is harder to justify. You could always sell your HPWC after market to make up for some of the expense.
 
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It almost seems as though Tesla guaranteed the vendor of the HPWC a certain minimum volume and then found that not enough people were ordering them. Hence the bundle to move product...just a guess, of course.
 
Thanks SFO, but this is just about what I was previously told and while I'd hate to accuse Tesla of playing with us, I have no way to verify anything that they have told me regarding these chargers. I'm certain that Tesla has software that could be visualized for the customer to show exactly what was happening at each internal charger. While we have a High Power Wall Connector, it seemed unnecessary to install if we were getting the same effect off a 220 line. Until last week when I spoke to that technician.

This also creates confusion at public charging stations (which are confusing enough). If a level 2 charger is only kicking out 40 amps and I need 80, then we're never going to achieve the potential charging speeds that caused us to purchase that second charger.
 
Thanks SFO, but this is just about what I was previously told and while I'd hate to accuse Tesla of playing with us, I have no way to verify anything that they have told me regarding these chargers. I'm certain that Tesla has software that could be visualized for the customer to show exactly what was happening at each internal charger. While we have a High Power Wall Connector, it seemed unnecessary to install if we were getting the same effect off a 220 line. Until last week when I spoke to that technician.

This also creates confusion at public charging stations (which are confusing enough). If a level 2 charger is only kicking out 40 amps and I need 80, then we're never going to achieve the potential charging speeds that caused us to purchase that second charger.

If you don't need or can't install a HPWC charger in your home, and never plan to take roadtrips in California where you would either use a 70A or 80A charging station (like those at Rabobanks along 101, or the HPWC's at Tesla service centers, or the Clipper Creek 70A units along I-80 near Sacto), then there is no need to get a second/dual charger. But just to be clear -- you don't need a HPWC to actually use the second charger. I have used 70A stations maybe 20+ times since getting the car. Probably hundreds of others have used dual chargers with non-HPWC higher amp stations. If I didn't have a second charger, I only would have been charging at 40A instead of 70A at these higher amp stations. And if you only planned to use your UMC with a NEMA 14-50 outlet in your garage, you don't need twin chargers. So, from a purely technical perspective, what the technician told you is wrong. From a practical perspective, because Tesla won't install the dual/second charger unless you also agree to purchase a HPWC, then what the technician told you is literally true -- you need the HPWC.

Oh, and welcome to TMC! Search is your friend here. You will learn tons by using it.
 
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A single 10 KW charger can handle up to 40A, roughly speaking. The math is a max of 250V * 40A = 10,000W (10KW). In most cases, you get 240V and not 250V, so you get 9.6KW maximum into one charger.

So (assuming 240V) you only need a single charger if you're charging at or below 40A. Anything above 40A will require the dual charger option in your car. Or to put it in the terminology they used when talking to you, the second charger "kicks in" at 41A. The car does not care which charging station is used. The advantages to the HPWC are that it's a very high power charging station for (IMHO) a very low price, which allows me to keep the UMC in the car at all times.
 
My apologies SFO, but aren't you simply saying that you believe the first rep that the second charger kicks in at 40 amps? We have to travel 135 miles into LA, then roll around a bit. Full charge is 270. We use 3/4 of the charge and need to fill up to be able to return. We use the Supercharger in Hawthorne, but are looking for alternatives. The car has dual chargers already.

So far I have not been able to locate the 70 amp chargers you refer to. The longest part of idle time is spent in the Long Beach area. Your statement that, "If I didn't have a second charger, I only would have been charging at 40A instead of 70A at these higher amp stations," is the first time I have heard anyone claim that they are certain that the second charger kicks in at 40.
 
So far I have not been able to locate the 70 amp chargers you refer to. The longest part of idle time is spent in the Long Beach area. Your statement that, "If I didn't have a second charger, I only would have been charging at 40A instead of 70A at these higher amp stations," is the first time I have heard anyone claim that they are certain that the second charger kicks in at 40.

Then you've been listening to the wrong people. Welcome to TMC, where the knowledge is vastly superior. :)

To charge at level 2 AC, anything above 40A, you need the second charger. You will only charge at 40A at stations capable of doing over 40A with a single charger.
 
My apologies SFO, but aren't you simply saying that you believe the first rep that the second charger kicks in at 40 amps? We have to travel 135 miles into LA, then roll around a bit. Full charge is 270. We use 3/4 of the charge and need to fill up to be able to return. We use the Supercharger in Hawthorne, but are looking for alternatives. The car has dual chargers already.

So far I have not been able to locate the 70 amp chargers you refer to. The longest part of idle time is spent in the Long Beach area. Your statement that, "If I didn't have a second charger, I only would have been charging at 40A instead of 70A at these higher amp stations," is the first time I have heard anyone claim that they are certain that the second charger kicks in at 40.

You might want to read through this thread, and in particular the last 10 or so posts, just to get some further information. There's some pretty clear info on advantage of dual chargers and limitations of single chargers. In the case of the OP in this other thread, after complaining that he was only getting 40A at the Clipper Creek station in question, it was quickly determined that the OP only had a single charger on the car to which others including myself responding, "No way, really, I don't believe it, incredible, unbelievable, who would have known!?!" :rolleyes:
http://www.teslamotorsclub.com/show...er-(need-twin-chargers-to-take-full-advantage)

In terms of LA, I don't know what charging stations are available in the wild that would offer more than 40A (other than the Hawthorne SC which you can take full advantage of whether you have a single charger on your car or two). Here is another thread I started months ago asking people to identify all 70A or 80A charging stations in California, but doesn't look like anyone has updated it in a while to include anything that has surfaced in SoCal south of Goleta other than Tesla service centers.

http://www.teslamotorsclub.com/show...ations-in-California?highlight=70A+california

Any yes, the first person you spoke to was correct. The second charger essentially "kicks in" at anything north of 40A. That is the case whether you are using a HPWC at 80A or a Clipper Creek version at 70A, or something else at north of 40A. I'll repeat: You don't need a HPWC to take advantage of the second charger, but you do need a charging station that has more than 40A. Anything at 40A and below will charge at the same rate whether you have a single charger onboard or two.
 
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Then you've been listening to the wrong people. Welcome to TMC, where the knowledge is vastly superior. :)

To charge at level 2 AC, anything above 40A, you need the second charger. You will only charge at 40A at stations capable of doing over 40A with a single charger.

Thanks Flasher. One week ago I made a special trip (in an ICE) to a Tesla Service Center where I was told that the only time that second charger kicks in is at 80 amps. I did indeed come to TMC for your superior knowledge. I've heard two different things from Tesla and I wanted to talk to owners, so thanks for your help. As I said before, I have not been able to find even 70 amp chargers in the Long Beach area, let alone 80 amp.

Here's the bottom line. I need to put 170 miles on this battery as fast as I can, as close to Long Beach as possible. So far, driving to Hawthorne has worked, but I still need to double back to Long Beach and then drive another 135 miles to get back home.

There is a concern with the lines beginning to form at the 4 charging stations in Hawthorne. So far, so good, but I wanted a backup.

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Thanks for the links SFO, I'll read through them.
 
The only available charge stations that are over 40A (and benifit from twin Model S chargers) are the Rabobanks up the 101 coast that were initially installed for Roadster (which all have a twin charger equivalent). The most Southerly bank with a plug is Goleta). Other than that in CA there is only homeowner or odd private business that has one installed.

The world's charging standards are vastly behind Tesla's so unless it was installed for a Tesla it will be slow.
 
Just thought I'd throw in a bit about bundling the dual chargers with the HPWC. I complained to Tesla Ownership, as there are several Roadster HPC (70 Amp) available, and the Canadian Sun Country Highway has a number of 90 Amp (70 usable) Clipper Creek EVSEs. Also, there are a couple of efforts underway to emulate the Sun Country highway in WA state.

The follow is the response I received:

Hi William,

I received your note this morning regarding our new option to bundle the High Power Wall Connector and Twin Charger feature.

We made this decision in clarify for customers the benefit Twin Charger feature offers, and what it requires. Fortunately, under the circumstance that a customer cannot install the Wall Connector, we will accept a return of the device. This is the only work around we have currently, but I’ll investigate if we can add the Twin Charger into the configuration manually, without addition of the Wall Connector.

Thanks for sending us the suggestion. If you have any other questions, feel free to contact me.


So, looks like they will work with a person that wants dual chargers and not the HPWC. I got my car before the bundling, and have enjoyed 70 Amp charging at Roadster spots several times.

Also, currently planning for a four or five day trip north of the border, and 70 Amps at lunch sure is nice.
 
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Thanks Flasher. One week ago I made a special trip (in an ICE) to a Tesla Service Center where I was told that the only time that second charger kicks in is at 80 amps. I did indeed come to TMC for your superior knowledge. I've heard two different things from Tesla and I wanted to talk to owners, so thanks for your help. As I said before, I have not been able to find even 70 amp chargers in the Long Beach area, let alone 80 amp.

Here's the bottom line. I need to put 170 miles on this battery as fast as I can, as close to Long Beach as possible. So far, driving to Hawthorne has worked, but I still need to double back to Long Beach and then drive another 135 miles to get back home.

There is a concern with the lines beginning to form at the 4 charging stations in Hawthorne. So far, so good, but I wanted a backup.

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Thanks for the links SFO, I'll read through them.

If you're just looking for a backup, you might try searching Plugshare to see if anyone has a HPWC or Clipper Creek station in their home they might be willing to share with you in a pinch. I just searched the Tesla Highway on Google and didn't find any 70A or 80A stations in the Long Beach area (I believe the other 70A stations in California are all identified with blue pins on the map. There are some HPWC at Tesla service centers up here in NorCal that have not yet been added to the Tesla Highway.)
 
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Thanks SFO, but this is just about what I was previously told and while I'd hate to accuse Tesla of playing with us, I have no way to verify anything that they have told me regarding these chargers.

I have twin chargers and have used a 70 amp charger and trust me, I charged a lot faster than a 40 amp charger. The personwho told you they only worked with an HPWC or would only "kick in" (what's that even mean? sigh) was ignorant, twisting things to mislead you, or an idiot. Hopefully just ignorant (I'm not sure that's the best possibility, actually).

I'm certain that Tesla has software that could be visualized for the customer to show exactly what was happening at each internal charger. While we have a High Power Wall Connector, it seemed unnecessary to install if we were getting the same effect off a 220 line. Until last week when I spoke to that technician.

Not sure what you mean by "same effect"; is your 220 line 40 amps? The twin chargers won't get you any more juice out of that than a single charger.

This also creates confusion at public charging stations (which are confusing enough). If a level 2 charger is only kicking out 40 amps and I need 80, then we're never going to achieve the potential charging speeds that caused us to purchase that second charger.

"never"--well, if you have no over-40-amp chargers around you (and expect none will be built anywhere you'd want to charge), then yes, never. ;-) But never's a mighty long time. I've used a J1772 70-amp charger as well as an HPWC; both were a lot faster than a 208/30 amp J1772 charger or even my old 6-50 outlet.

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One week ago I made a special trip (in an ICE) to a Tesla Service Center where I was told that the only time that second charger kicks in is at 80 amps.

Gah, I want to go find that person (a Service Center employee, of all employees, should know better!) and shake them. Sigh. ;-)

As I said before, I have not been able to find even 70 amp chargers in the Long Beach area, let alone 80 amp.

I don't know about California, but over-40-amp chargers are rare in my area (I've used a 70-amp one in Richmond, though). But I expect (hope) they will become less rare over time....
 
The only available charge stations that are over 40A (and benifit from twin Model S chargers) are the Rabobanks up the 101 coast that were initially installed for Roadster (which all have a twin charger equivalent). The most Southerly bank with a plug is Goleta). Other than that in CA there is only homeowner or odd private business that has one installed.

The world's charging standards are vastly behind Tesla's so unless it was installed for a Tesla it will be slow.

I wouldn't say those are the only high power stations. My son and I went on a road trip in August from San Diego to Reno / Lake Tahoe and we used high powered EVSEs not only at Rabo banks but also in San Luis Obispo, Auburn (at the Clipper Creek HQ) and in Reno. Plug Share is your friend and it only takes a few minutes to find these stations. There's more of them out there than you might think...If you're going to go on road trips, I highly recommend dual chargers on the car....
 
Then you've been listening to the wrong people. Welcome to TMC, where the knowledge is vastly superior.

hah!

I wouldn't say those are the only high power stations. My son and I went on a road trip in August from San Diego to Reno / Lake Tahoe and we used high powered EVSEs not only at Rabo banks but also in San Luis Obispo, Auburn (at the Clipper Creek HQ) and in Reno. Plug Share is your friend and it only takes a few minutes to find these stations. There's more of them out there than you might think...If you're going to go on road trips, I highly recommend dual chargers on the car....


yep. Clipper Creek CS-100 is a J1772 100amp charger (80amp continuous). I actually plan on installing one of these at my next house and put it on PlugShare and trying to get my cousin to put one of these down at his business in Cape May NJ. This unit can charge the Model S at same rate as the HPWC, but since it's J1772 that means that any EV can use it - not just a Tesla. There's nothing special about the HPWC over the Clipper Creek. Why bother getting the HPWC then? There is only 1 reason that I can think of - price. HPWC is $1200 while the Clipper Creek CS-100 is $2200. So the HPWC is actually a damn good deal for the money. You just won't be able to charge anything other than a Tesla with it.

clippercreek.png
 
I had been told by a Tesla Rep (over the phone) that the second charger kicks in at 40 amps but while speaking to a technician at a Tesla Service Center I was told that the second charger only kicks in at 80 amps and requires Tesla's High Power Wall Connector. I'm apt to believe the service tech as the phone rep was probably working off a script while the service guy worked on these cars every day.

Am I the only one who was given that 80 amp figure?
Based on empirical evidence, I believe this to be incorrect. Elaborating...

When I charge at 80A on my Model S HPWC (after tapping past the 60 limit dialog, damn you 4.5), the amperage ramps from 0 to 40, then pauses, then ramps from 40 to 80.

When I charged to 72A on Bellevue Store's Model S HPWC, the amperage ramped from 0 to 36, then paused, then ramped from 36 to 72. Then the cable overheated so I turned it down (already reported to Tesla and discussed previously) to 60A.

When I charge to 60A on a Model S HPWC, the amperage ramps from 0 to 30, then pauses, then ramps from 30 to 60.

The twin charger is definitely used somewhere at or above 40A limit and definitely up as low as 60A limit. I haven't tried setting the limit to like 42A to see what happens. But I might, sometime soon, out of curiosity.
 
Based on empirical evidence, I believe this to be incorrect. Elaborating...

When I charge at 80A on my Model S HPWC (after tapping past the 60 limit dialog, damn you 4.5), the amperage ramps from 0 to 40, then pauses, then ramps from 40 to 80.

When I charged to 72A on Bellevue Store's Model S HPWC, the amperage ramped from 0 to 36, then paused, then ramped from 36 to 72. Then the cable overheated so I turned it down (already reported to Tesla and discussed previously) to 60A.

When I charge to 60A on a Model S HPWC, the amperage ramps from 0 to 30, then pauses, then ramps from 30 to 60.

The twin charger is definitely used somewhere at or above 40A limit and definitely up as low as 60A limit. I haven't tried setting the limit to like 42A to see what happens. But I might, sometime soon, out of curiosity.

Keep us updated with the overheating issue. How did you know the cable overheated?