Home Charging kit

OB2

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Currently a Tesla Solar customer and I’m interest in purchasing the home charging system for my CyberTruck. Does anyone have any experience with that or can offer first time experience tips? Thanks in advance.
 

ajdelange

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The High Powered Wall Charger (HPWC) is capable of delivering 80 Amperes when wired to a 100A circuit. More than one of these can be connected to that circuit for charging multiple cars with the 80 A shared between them. The most current current production S,X and 3 can draw is 48A but older X's can take up to 72. 80A is 19.2 kW for 19.2 kWh delivered each hour. As the CT's will need about 0.5 kWh to go a mile this translates to about 38 miles per hour range added at 80 A - actually probably more like 36 because the chargers are not 100 % efficient.

Because the CTs energy use is appreciably more than Telsa's current largest offering (the Model X) which takes about 300 Wh/mi I speculate that they will probably return to 72 A (or maybe even 80) maximum charge rate at least in the Tri Motor as picking up over 300 miles in a 10 hour overnight charge seems reasonable for a truck with 500 mile range (one usually charges from 50% to 75% or 80% most of the time).

There is tons of discussion on HPWC installation on other Tesla fora most of which centers on how big a circuit one should put it on. Most people settle for a 60 A circuit because up to and including that capacity no separate, lockable disconnect switch is required by the NEC (but local codes might demand it) and that's the most a single Tesla of the current design can take, If Tesla sticks with 48 A rectifiers there is no point to going to a larger circuit unless you plan to charge multiple Teslas. If Tesla installs larger chargers in the CT's then there is motivation to go to heftier circuits. Whether you can do that or not depends on your service and your panels and your willingness to put out more $ for more miles/hr of charging. From this perspective it may be wise to wait to see what Tesla decides to do with respect to charger size (note the HPWC isn't a charger - it is EVSE that feeds the charger which is in the car or truck) in the CT's. You will need to get an electrician in, one who has done EVSE installations before to evaluate your particular situation.

You can go to the Tesla store online and download the HPWC manual.
 
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VI Tesla

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Currently we're just plugging our Model 3 into my existing 30 AMP socket I had installed for my welder. Don't really see the need for the home charging kit. Even if the battery is drained we get a full charge over night, even dialed back to 25 AMPs to protect circuit. Of course generally we only let the battery get to 50% then it's only four hours to charge it back up. We've owned the car since July and have only once charged it away from the house. Yes kit will charge faster, but that's also not great for the batteries. Anyway personally I just can't justify the expense.
When I get my Cybertruck still no issue as charging would be staggered between vehicles Currently Model 3 charged once a week. Of course this depends on you own commute/use.
 

ajdelange

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There is no "right" answer. A couple of things to think about though:

A)The 3 consumes about 230 (?) Wh/mi. The CT will consume about twice that and will, thus, for any given sized charger, take twice as long to get the same number of miles into the vehicle. Thus if you need to add 100 miles and it takes a bit under 4 hours to do that with a 30 A charger it will take a bit over 8 hours to get that many miles into a CT. The larger consumption argues for a larger charger but of course one can easily live with 30 A and a CT if he has 8+ hours available to charge it.

B)The wall charger installs permanently and neatly stores the cable when not it use. Many people do not like going out without the UMC in the car in case necessity for charging arises unexpectedly on the road. With the HPWC one never takes the UMC out of the car unless it is needed on the road. One can gin up various schemes to keep the UMC and cables off the ground or floor of the garage and one can buy another UMC for home charging thus allowing the one that came with the car to stay with the car. I believe a UMC costs about the same as an HPWC.

C)By the book no more than 24 A should be taken from a 30 A circuit used to supply EVSE.
 

CyberG

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I'm not sure that charging at 30A as opposed to 80A has any appreciable added wear on the batteries. Supercharging, maybe, but even that is equivocal whether it causes much extra wear.
 

ajdelange

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For a 100 kWh battery 80 A = 19.2 kW = .192C. For a hypothesized 200 kWh battery charged at 80 A it is 0.096C which is the same as one would get charging the 100 kW battery in an S or X at 40A. Thus one definitely need not worry about charging the CT at 80 A from the battery life perspective.
 

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The High Powered Wall Charger (HPWC) is capable of delivering 80 Amperes when wired to a 100A circuit. More than one of these can be connected to that circuit for charging multiple cars with the 80 A shared between them. The most current current production S,X and 3 can draw is 48A but older X's can take up to 72. 80A is 19.2 kW for 19.2 kWh delivered each hour. As the CT's will need about 0.5 kWh to go a mile this translates to about 38 miles per hour range added at 80 A - actually probably more like 36 because the chargers are not 100 % efficient.

Because the CTs energy use is appreciably more than Telsa's current largest offering (the Model X) which takes about 300 Wh/mi I speculate that they will probably return to 72 A (or maybe even 80) maximum charge rate at least in the Tri Motor as picking up over 300 miles in a 10 hour overnight charge seems reasonable for a truck with 500 mile range (one usually charges from 50% to 75% or 80% most of the time).

There is tons of discussion on HPWC installation on other Tesla fora most of which centers on how big a circuit one should put it on. Most people settle for a 60 A circuit because up to and including that capacity no separate, lockable disconnect switch is required by the NEC (but local codes might demand it) and that's the most a single Tesla of the current design can take, If Tesla sticks with 48 A rectifiers there is no point to going to a larger circuit unless you plan to charge multiple Teslas. If Tesla installs larger chargers in the CT's then there is motivation to go to heftier circuits. Whether you can do that or not depends on your service and your panels and your willingness to put out more $ for more miles/hr of charging. From this perspective it may be wise to wait to see what Tesla decides to do with respect to charger size (note the HPWC isn't a charger - it is EVSE that feeds the charger which is in the car or truck) in the CT's. You will need to get an electrician in, one who has done EVSE installations before to evaluate your particular situation.

You can go to the Tesla store online and download the HPWC manual.
I have two of them. One hooked up to 80 Amps and the other hooked up to 30 Amps. (I got a signed one for free with 2 referrals.) I definitely recommend having your electrician run wires for the 80A circuit. Don't mess with anything below that. The 30A is fine for every day charging, but there are times when I need a quick charge, so I move into the other garage and use the 80A.
 

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I'm assuming it is much more convenient to charge in the garage with the 30 A service as it is perhaps connected to the house whereas the one with the 80A service requires more walking. But your post may lead to some confusion on the part of those that are unfamiliar with this equipment. Thus another list of points to ponder:

A)An HPWC can deliver a maxium number of amperes set at configuration and dependent on the size of the circuit breaker. For a 100 A breaker that is 80 amps. For an 80 A breaker it is 64 A. For a 30 A breaker it is 24 A.

B)The car can be set for any charging level, from the Car or the app or from some third party apps to whatever level you like below the maximum.

C)An 80 Amp circuit supports up to 64 A charging which is more than enough to feed current production cars which, with their two 24 A modules can take, at most, 48 A

D)Some older cars have 3 modules and can thus accept 72 A - more than can be supplied by an 80 A circuit

E)The Cyber Trucks (or at lest the TriMotor) will doubtless have at least 72 A charging capacity and possibly 80 requiring a 100 A circuit

F)Multiple HPWC's can be connected to the same circuit. They will share the load between the vehicles connected to them.

G)Slower charging may or may not lengthen battery life appreciably and is certainly workable if you have the time

Thus it seems to me that if planning for a CT or CTs the most charging flexibility is obtained by putting each of multiple HPWC on separate 100 A circuits which would allow maximum rate charging of two CTs but a much less expensive approach for charging a CT and a 3 or X or S would be to put two HPWC on the same 100A circuit. As I have said before, the is no single correct answer to the configuration question. For more information on the HPWC go to the Tesla store and download the installation guide.
 

Fabville

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Just a quick note, Tesla recently released the Gen 3 Wall Connector. It’s physically smaller, now includes WiFi capability, and only has a max output of 11.5 Kw /48 amp output. I wonder if the Cybertruck will have 48 amp onboard charger or if they’ll consider a dual onboard...

https://shop.tesla.com/product/wall-connector
 

bfdog

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Thus it seems to me that if planning for a CT or CTs the most charging flexibility is obtained by putting each of multiple HPWC on separate 100 A circuits which would allow maximum rate charging of two CTs but a much less expensive approach for charging a CT and a 3 or X or S would be to put two HPWC on the same 100A circuit. As I have said before, the is no single correct answer to the configuration question. For more information on the HPWC go to the Tesla store and download the installation guide.
OP asked generally about HPWC and after digesting that word salad I feel like I need two 100 amp circuits, two HPWCs, and a substation in my garage. I wonder whether it depends on the daily commute expected whether high capacity charging is needed. Does anybody really have multiple 100 amp circuits available? What time is it? [AJ starts typing how to build a watch].
 

ajdelange

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OP asked generally about HPWC and after digesting that word salad I feel like I need two 100 amp circuits, two HPWCs, and a substation in my garage.
You do if you want to charge multiple vehicles as quickly as possible. Tesla's current and coming (CT) vehicles are considered to be 60 A loads when charging at the maximum rate which is 48A. It doesn't take a PHD in math to be able to figure that you can, therefore, only charge 1 Tesla at the maximum rate from a 100 A circuit. It also doesn't take advanced math to figure that you can charge two at the same time if you dial each of them back to 5/6 of the maximum rate(40A).

I wonder whether it depends on the daily commute expected whether high capacity charging is needed.
Yes, of course it does. Say you have a single Tesla which you must drive 100 miles per day and that's its consumption is 400 Wh/mi. It will need 40 kWh of juice per day. At the maximum rate the chargers in Teslas deliver a bit less than 48*240/1000 = 11.5 kW say it's 11. Thus you must charge at the maximum rate of 40/11 = 3.6 hrs each night. If you have 3 cars each of which goes 300 miles per day the story is quite different.

In a typical scenario you might have a subpanel with A 100 A breaker and two or three HPWC each fed by a 60A breaker. A Tesla arrives and plugs in. The HPWC and car communicate with one another and the car requests 48A (unless you have set it to request less). The HPWC talks with its brothers (over WiFi) and seeing that there are no other cars present tells this first Tesla that it can have 48 Amps and that car starts to charge at that rate. Now a second Tesla comes along and plugs in. It too requests 48A but when its HPWC communicates with the others it finds that 48A is already being taken out of the total 80 available from the subpanel (current capacities must be derated to 80% of labeled ratings) leaving 32 A capacity available. Thus it could grant the second vehicle 32 A until such time as the first car is finished charging or it could reduce the first car's portion to 40 A and grant the new comer 40A as well. Which of these sharing algorithms (or perhaps both or others) will be available remains to be seen. At this time the new HPWCs are being sold but the sharing firmware is not available. When a third car comes along and plugs in it would get nothing under the grant whatever is left algorithm until one of the first two finished charging and one third of 80 A under a split it up equally algorithm.

In any case you must determine how many total kWh of charging you need at your site each night. You then divide the site's charging capacity in kW to get the number of hour's required to charge all the cars. Let's use the previous example of 40 kW hr for each three cars. That's a total of 120 kWh. A subpanel with 100 A breaker is capable of providing 80 A of charging which is 19.2 kWh at 240V. Thus you will need 120/19.2 = 6.25 hours charging time to top up three cars from a 100 A circuit.

I'm sure all this is "word salad" so the message to take away is that the HPWC will be (via OTA firmware improvement - they are not there yet) very flexible in how they manage charging such that multiple vehicles can be managed. The word salad has to be translated into a system configuration. If you can't do that then you'll need to consult someone who can.


Does anybody really have multiple 100 amp circuits available?
As the example above showed if you have 12.5 hours available each night you can charge 240 kWh worth of miles with a single 100 A circuit with 2 or more HPWC on it. At 3 or more miles per kWh for S, X and 3 and 2 or a little more for a CT that's a lot of miles (500 - 800).

But yes, modern houses have pretty hefty service and BEVs are at least partially responsible for this. I have 400A service in one house and 600 in the summer "cottage" though I have never taken more than 150A from either.

What time is it? [AJ starts typing how to build a watch].
I'll answer that with a little anecdote. I was once in a meeting with Gernot Winkler. As is the case with most meetings it was a pretty boring so I began to wonder what sort of watch the man who was running the Naval Observatory's Time Service Department might wear. So I contrived to drop my pencil and while recovering it glance up his jacket sleeve. He was wearing no watch at all. At a break I ran into one of my colleagues in the hall and reported to him that Gernot Winkler does not wear a watch. "Of course not" he replied without a moment's hesitation. "It's whatever time he says it is." I always thought Bill was a pretty bright guy but I subsequently found out that Einstein had, in response to the question "What time is it?" had answered with "It is whatever time the guy with the clock says it is." I enjoyed working on that stuff. It's fun to be able to go to a party and tell people you are a horologist.
 
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