Charging with 30 amps

[Kurt Carlson]

That chart is pretty spot on I guess, good to know!

Also, Model Y charging specs look to be very similar to Model 3, (earlier I guessed it would be somewhere between 3 & S)

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[Jhodgesatmb]

Has there been any real progress on plug-less charging that might play a role with CT?

 

[Dids]

Has there been any real progress on plug-less charging that might play a role with CT?

Its probably never going to happen. To get the transfer rate required the AC frequency needs to be high and unfortunately causes serious heating. As in if a leaf blows into the field it lights up. If you stay low frequency the coils are so large that carrying it around isnt worth it. May be possible once they find a high temperature superconductor? I think a better bet is a robotic plug.

 

[Jhodgesatmb]

Its probably never going to happen. To get the transfer rate required the AC frequency needs to be high and unfortunately causes serious heating. As in if a leaf blows into the field it lights up. If you stay low frequency the coils are so large that carrying it around isnt worth it. May be possible once they find a high temperature superconductor? I think a better bet is a robotic plug.

I wasn’t clear and I apologize. I meant as a replacement for the home charger not for remote charging, and I purposefully said plug-less because I am not convinced that contactless is practical or safe. That said, there are bus chargers in service that contact from the top that work so I don’t think ‘never’ is realistic either.

 

[Fabville]

I wasn’t clear and I apologize. I meant as a replacement for the home charger not for remote charging, and I purposefully said plug-less because I am not convinced that contactless is practical or safe. That said, there are bus chargers in service that contact from the top that work so I don’t think ‘never’ is realistic either.

I don't think I would consider this significant progress, but this company does have inductive charging, it requires components to be installed on the vehicle:
https://www.pluglesspower.com/shop/reserve-tesla-model-s/

I remember seeing a mat or pad unit that you could drive over several years ago, I'm not sure if it was from the same company or someone else. If I remember right the price was at least $2-3K and it was slower charging than what you would get from a Level 2 plug-in EVSE.

 

[Dids]

I wasn’t clear and I apologize. I meant as a replacement for the home charger not for remote charging, and I purposefully said plug-less because I am not convinced that contactless is practical or safe. That said, there are bus chargers in service that contact from the top that work so I don’t think ‘never’ is realistic either.

Oh yes that would be cool. But I think it would be especially useful in public chargers especially if the car can drive away to a parking spot by itself to avoid idle charges.

 

[Kurt Carlson]

Are you talking about Wi-Tricity? I think it is pretty efficient (according to their youtube video) but probably not super cheap. Their video made a good point about wireless charging being a good solution for self driving cars run by Tesla or Waymo.

 

[Fabville]

I saw discussion a few years back for a concept of wireless EV charging as the vehicle drove along a highway. Looks like Stockholm might have an electric highway with a contractor from the vehicle transferring electricity from a track system in the road.

 

[Fabville]

Here’s a video on Qualcomm’s Halo idea, it would be amazing to see something like this implemented eventually.

 

[ajdelange]

Wireless charging is technically feasible. It is going to be a bit less efficient than a direct connection but in the great scheme of things who cares if a nominal charge takes an extra hour. The real issue with it the receiver which needs to interface with the vehicle mechanically, electrically and software wise. Thus the route to installation on the CT will probably involve the development of an industry accepted standard (I think this is underway) followed by Tesla deciding whether this is a feature they want to offer their customers or not. My X has it (for cell phone charging) and that's nice but not something I'm that excited about. It is a bit of a PITA to fiddle with getting that little plug into that little jack on the phone. Putting the charging plug into it's receptacle is much easier.

One interesting aspect of it for EV charging is that it was one of Nicola Tesla's major areas of endeavor. The Wardenclyffe tower was in essence a manifestation of this technology.

 

[Fabville]

Thank you, Fabville, for providing the chart. This is consistent with our findings.
We didn't go to the expense of installing a Tesla Wall Connector (although they do look very cool).
Our Gen 1 Mobile Connector cord uses a NEMA 6-50 adapter that plugs into our welder's 40A outlet. The outlet power comes from two 40A circuit breakers in a 50A sub-panel in our barn. Our MS P-85 gets charge rate of 22-23 MPH for routine charging to ~ 80% capacity.
The display on the Tesla's screen indicates it is charging at 30 amps.

I installed a NEMA 14-50 outlet in our garage and wired up a plug for the wall connector, having the option to unplug was more appealing than going the hardwire route for me. Welders were a reason I did this, but I currently only have a 110v Hobart.

 

[azjohn]

One interesting aspect of it for EV charging is that it was one of Nicola Tesla's major areas of endeavor. The Wardenclyffe tower was in essence a manifestation of this technology.

And if it wasn't for the meddling J.P. Morgan who knows how far Tesla would have gotten with the idea of wireless electricity

 

[ajdelange]

I assume that is tongue in cheek. He wouldn't have gotten very far as his concept was flawed. Unfortunately the poor man lost his mind in his later life. J. P. Morgan was wise enough to suspend funding of research that was going nowhere. Refusing to give a mad man more money isn't exactly meddling but as I said I assume this was meant as a joke.

 

[mggoulet]

First off 30A @ 240V = 7.2 kW. The charger in the car is about 90% efficient meaning about 6.5 kW will wind up going to the battery. In one hour that means 6.5 kWh. Now it gets a little tricky as we don't know how much the car needs to go a mile. That depends both on the car and how you drive it. Assume that the number will be 0.450 kWh/mi. It's probably going to be something like that. Then you would get 6.5/0.45 = 14.44 miles per hour or 144.4 miles in a 10 hour period. That should be enough for most people.

As to the Evenflow device - EVSE must be the only thing connected to its branch circuit. Here you would have the Evenflow connected to a branch circuit with two devices (the washer/dryer and the EVSE) connected to the Evenflow. Does that satisfy 625. 41 through the load shedding provisions of 625.42? I have questions and your local inspector might too. Contact an electrician. Presumably you will be using one for the installation rather than doing it yourself. He should know how your local authority regards such a device. It is their opinion which counts in the last analysis.

There is one other thing that needs to be considered here and that is that if the Evenflow is connected to a 30 amp breaker it must be derated to 24 amps (0.8*30) in order to comply with the code. Thus would mean 11.5 mi added range per hour instead of 14.4 and 115 miles in 10 hrs. That should still be enough. If you install a 30 amp plug at the output of the Evenflow and charge with the UMC supplied with the CT using the correct adapter for a 30A plug the UMC will take care of this derating automatically. An alternative is to install a 50A breaker in the main panel and to hard wire a wall charger to the Evenflow output. The wall charger would be set for 50A feed and thus limit the vehicle to drawing 40A. This would give you an extra 16 A charging relative to what you can get from a 30A breaker feeding the Evenflow. This would give you 240*50*.8*.9/450 = 19.2 miles added range per hour. The question now is as to whether your panel can support the removal of a 30A breaker and replacement of it with a 50A breaker. The extra load is actually only 10A and the liklihood is, therefore, that it very well can. Again, a local electrician who knows the inspectors will have a good idea as to whether this would be acceptable.

 

[mggoulet]

Bonjour ajdelange, I have 400 amps with 2 panels of 64 entrance... only 10 free... so, must I by a barker of 50 amps... or more for the future CT.???