Trying to get ahead of delivery -- home charger questions

ajdelange

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I think you are probably right about that. I am guessing that the maximum will be 72 A because that's 3 modules of 24 A each two of which are found in current production cars and three of which are found in some pre 2019 cars. The other possibility is 80 A, the maximum the HPWC will support. There were some early Model S than had 80 amp chargers. If the CT indeed consumes 500 Wh/mi then 72 A will charge at 72*240/500 = 34.6 mi/hr and 80 A will give 80*240/500 = 38.4 miles per hour for full charge times of 14.6 hrs or 13 hrs respectively (not that you would ever charge fully).

I just noticed from a picture of the Semi that it has multiple charging ports. Is that a possibility here?
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Garden_Aum

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I was being a bit tongue in cheek. I went to the linked website and it is pretty clear this is vaporware at this point in time. A few things would have to happen before using the car to power the house could happen:
1)The NFPA would have to change the NEC to allow powering the house from a vehicle. The current NEC requires that EVSE (the thing that goes on the wall that many people call a charger even though it isn't) installed in the US must have circuitry to PREVENT reverse flow from the car.
2)The manufacturers would have to come together with EVSE manufacturers and the utilities to come up with standards so that
Tom's car would interface with Dick's EVSE which in turn would not upset Harry's power company.
3)The manufacturers would have to start making cars that met the new standard

All this is, of course, doable. I think it is being done, at least on an experimental basis, in Asia and Europe.
I personally would rather have the 3rd generation Tesla power walls rather than using my vehicle as a battery storage system for my home. So, even if it were possible to use my vehicle as back up power I would not.
 

dempster

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I just ordered a HPWC as well :)
 

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I own a P85 Model S, My home charger is 80A, dialed down to 64A. I opted for the dual chargers, that they are no longer offering. I add miles at about 54mi/hr, also faster at superchargers. Would be really nice to see the dual chargers offered for the be Cybertruck.
 

Saskateam

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I am planning to put in a 125 amp sub panel in the garage to accommodate charging. Looks like I should plan a 100amp breaker for charging the CT if it does come with the dual charger.
 


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Had a 100amp Circuit & Wall Charger installed today (for the model 3)....plan for a second wall charger to run in series on the same circuit when I get the CT.....the 3 maxes at 44 mi/hr charge (48 amps)....guessing the Cyber Truck with significantly larger battery will have a faster internal charger...otherwise it will take 14 hours for a full charge.
Ok, they just switched to a new wall charger that cant be wired together to share the 100amp circuit...and the new one has an 18' cord and is limited to 48amps....kind of screwed up my plans to add a second gen 2 HPWC to the one I just installed....so now I have to decide if I buy one now 2 years early or wait and see what the CT can use and if a diff charger or what happens in the future.....
 

Saskateam

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Ok, they just switched to a new wall charger that cant be wired together to share the 100amp circuit...and the new one has an 18' cord and is limited to 48amps....kind of screwed up my plans to add a second gen 2 HPWC to the one I just installed....so now I have to decide if I buy one now 2 years early or wait and see what the CT can use and if a diff charger or what happens in the future.....

Take the wait and see approach. Or try to find an older charger.
 

ajdelange

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It's true. Take everything I've said prior to this post and throw it out the window (which you may have done anyway)! The question is why they did this. First thought that always comes to mind is the lawyers suggesting that there may have been fires or overheating with the Gen II units. Or perhaps people had been hit with inspection violations when they installed them without the additional disconnect connect required over 60 A which some people did. Second thought is, of course, profitability. A 48 A contactor is cheaper than an 80 A contactor. So are terminal blocks etc.

Sharing will still be available but they want each unit on its own breaker. Perhaps the code has been interpreted in such a way that sharing of multiple units on the same breaker (as was done in Gen II) is not such a great idea. One gets effectively the same arrangement if a sub panel is used i.e. there is one breaker for Tesla chargers and its capacity will be shared with the differences being that the communication is done through WiFi and there is a separate disconnect (breaker) on the sub panel for each station.

As the fastest allowed charge rate in a current production Tesla is 48A there is no reduction in performance for any car you can buy today. But the biggest battery in the current portfolio is 100 kWh. The implications of 11 kW in a vehicle with a 200 kWh or larger battery that consumes 500 Wh/mi are charge times about double what one would experience with a Model X. This makes me wonder if the CT will have multiple ports as the Semi does. With that arrangement a multi Tesla family would install 2 Gen III HPWC and use one to charge each vehicle or both to charge the CT.

This all really suggests that people hold off on deciding on what to buy until more details on CT charging become available. Can't do that, of course, if you are buying a Tesla car now or in the near term unless you are willing to live with the UMC in the interim.
 

Saskateam

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Where did you get your crystal ball?

I am using a magic eight ball to predict the future. Can I afford the CT? “Seems doubtful”. Will it fit in the garage? “Likely.” Will it charge faster? “Yes” so I am planning for it anyways.
 


Garden_Aum

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I had my wall charger installed on 19 January. So far I really like it. It is hooked up to a 40 amp circuit. I will have an additional wall charger installed on the other side of my garage after I take delivery of the Cyber Truck.

Tesla Cybertruck Trying to get ahead of delivery -- home charger questions wallCharger
 

Garden_Aum

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I’m planning on waiting myself and here is a good reason why. https://apple.news/Ab54BL6s8Q9W6NtIEvFs3iQ
I bet you the WIFI feature is to enable you to monitor and control the charge times on your vehicle. In addition to being very cool looking I bet you it will be very reliable. I recently had a Jukebox installed to charge my current PHEV; it also has a WIFI connection. So far, I have been very happy with it but, it thinks it is located in the wrong time zone. For some reason, it shows all times in PST and not EST. I may have to redo the setup procedures more slowly and look for the configuration option associated with time zones.
 

Frank W

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I bet you the WIFI feature is to enable you to monitor and control the charge times on your vehicle. In addition to being very cool looking I bet you it will be very reliable. I recently had a Jukebox installed to charge my current PHEV; it also has a WIFI connection. So far, I have been very happy with it but, it thinks it is located in the wrong time zone. For some reason, it shows all times in PST and not EST. I may have to redo the setup procedures more slowly and look for the configuration option associated with time zones.
Perhaps some of the current EV owners could weigh in on this. Would the WiFi have anything to do with the vehicles software updates?
 

ajdelange

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In the previous versions of the HPWC scheduling and monitoring were handled by the car and the car communicated with the charger via the communication wire pair in the cable. What was going on was reported to the driver via the car's network connection. (WiFi if present or LTE). The car would (through the communication wires) tell the charger what it was capable of and what the driver had requested (e.g. my X is capable of 72 amps but i often only ask fo 20). If the circuit has the requested amps available it would give the car permission to draw the requested amount. If not, the car would be given permission to draw what ever capacity were available to keep the total load below the maximum the circuit was set for. For example, an HPWC connected to a 100 A circuit would have its its dial set at D for 80A output and any Tesla built to date would be able to draw its maximum. Were that same charger wired to a 60 A breaker its dial would be set to 9 for 48 A maximum and that is the most any car would be able to get from it irrespective of how much it asked for. Now if in that latter case more HPWC were installed on that same breaker, their dials would be set for F (Slave mode) and an additional pair of wires for communication between them and the Master HPWC. If a second car plugs into a Slave set for 48 A the Slave will send a message to the Master requesting 48 A. If there is a car connected to the Master drawing 48 A there is no reserve on this 48 A max load circuit and the Master communicates to the Slave that no current is available to it. If the operator of the first car reduces the charging current to 30 A there are then 18 A available to the second car, that is communicated to the Slave HPWC and hence to the car which then starts charging at 18 A. When the first car completes charging the whole 48 A is available to the Slave and the second car can charge at 48 A.

The new HPWC are capable of 48 A at most and can thus be installed on breakers up to 60 A. The inter HPWC communication pair is gone as is the dial. The WiFi is there to assume the functions formerly taken by the dial and that pair. One configures an HPWC using a page served out by the HPWC on its own network. It isn't clear how sharing will be configured as sharing is not available at this time but the algorithm will be the same (or very similar) with the communications handled by "unit to unit WiFi". I expect driver control, scheduling and monitoring will be, as before, from the vehicle through the vehicle app.

The HPWCs will connect to your local WiFi network and can be addressed by the Mother Ship for things like firmware updates and this implies that other things could be done with respect to informing the user etc. But there really isn't much value in that as it is already handled pretty well by the cars.

I expect OTA updates will continue to be supported as they are today i.e. through the car's connection to the home WiFI network.
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