How many prime owners have invested in a L2 Charging station at home?

Correct. It's a capable-of-240V EVSE and the wiring is rated for 300V.

 

This is not a function of provider (they can give you a million amps if you want to pay for it). The limitation is your installed service panel. Older US homes (before air conditioning) had 60 amp service panels. Newer homes typically have at least a 200 amp panel, and some have more. The max load is determined by the installed disconnect or breaker at the top of the panel.

How did you measure your max current with a multimeter? That level of current is typically more than a RadioShack or similar multimeter can handle.

Power to your home in the US is two phases of 120, which combined together make 240. The left side of your service panel is one leg of the incoming service (120), the other side is the other leg (120). if you put in the correct breaker (two phase), you get both phases and 240V power.

208 is not typically found in homes; it is one leg of 3 phase commercial power. US home are 240V service to the home, which breaks down to service in the home of both 240V and 120V.

 

I think I'm going to be of the opinion that the 120V/12A produces less heat in the battery. It seems more logical just looking at 12A vs. 16A, then there is the additional time to dissipate the heat since the 120V takes over twice as long.

I have been wondering about one question that the Prime has asked twice now. It asks if it can run the A/C to cool the battery, and I'm not sure how to pick the yes choice, and by the time I can start trying to see, the message disappears. Of course, running the A/C to cool the batteries will use a lot more electricity, but to extend the battery life I would be willing to do this. That is just one of the hardships of living in Florida.

 

Like already stated by JB & Burnout, your OE Toyota EVSE works perfectly at 240 volts. At least do your homework on this before you spend roughly ~$199 on a Chinese built unit that comes with an ill fitting charge handle.

Using the Primes 120v Charger at 240 Volts, Cost $20 !!! | Page 4 | PriusChat

You need these 4 things things to make this work:

1) Your Prime
2) OE Toyota EVSE
3) A 240v receptacle
4) A conversion Pigtail


Rob43

 

If you use the Prime EVSE, you might get 240V but only 12A, not 16A. 240V*12A = 2.88kW while 240V at 16A is 3.84kW. Many commercial EVSEs are 208V from which the Prime will draw 16A for a total of 3.33kW.

So, while using the Prime EVSE at 240V will double your charge rate, it won't quite make it to the charge rates you get from a genuine L2 charger.

 

If the difference of about 20 minutes for a full charge is important to you, then spring for the genuine L2 charger.

 

Correct... but you need to spend the $$$ to get 16 amps, just like JB said.

For me personally, I just didn't want to spend ~$199 for a Chinese built EVSE that has an ill fitting charge handle. The money I and countless others have saved by building or buying a 240v conversion Pigtail equal over ~5000+ miles of free battery driving.


Rob43

 

I was fortunate in that my municipal electric utility gave me a rebate for putting in an L2 charging station, which essentially paid for the Chargepoint charging station. I paid for an electrician to put a 240V outlet in the garage, but that was real cheap, since the outlet is on the opposite side of the wall from my electric panel, with a total run of about 4 feet. There was even an existing opening in the wall with a blank outlet box, thanks to the home builder (home less than ten years old). So for me, it was pretty much a no-brainer.

BTW another reason that 240V charging takes a bit less energy than 120V charging is due to losses in the AC-DC converter, fans, and other control circuits, that are based on time used rather than energy.

 

Yep, the house I grew up in had a 60amp panel. I understand the main is the limiting factor for my 200amp service. The electrician that wired the house had a very sophisticated multimeter and showed me the voltage and amperage at install. Since then, my Carrier thermostat when in diagnostic mode tells me the operating voltage to the single digit with very slight fluctuations, but not the amperage.
Thanks for responding. I think a lot of people still use the old term 110/220v without knowing it's actually 120/240v.

 

@Rob43 @Lee Jay and @jb in NE thank you so much for all that information. I can build a conversion pigtail myself. I suppose the two hots on the 240V side (black and red) connect to the hot and neutral prongs on the 120V connector on the EVSE? Does it matter which one? I don't think so, but please advise if I am wrong on that. I believe 12AWG wire is sufficient for the pigtail. I still have to spend money running an underground wire from my basement panel to the driveway and installing an outdoor rated NEMA 6-20P 240V outlet.

There's just a bit of discomfort to the thought of plugging in the EVSE directly to a 240V circuit when there is no labelling telling me it's possible. I don't want sparks flying all over my driveway .

If it still outputs 12A instead of 16A, and the change to 240V doubles the charging rate, that means that for me it would cut it down to 3 hrs. Much better than 6 hrs. It would also save me a few hundred $$$ and accomplish the same goal, which is unplugging the car before I go to bed. Charging in 2 hrs is better than 3 hrs, but that's not a significant different to me when. Though I believe Rob says it was 2 hrs and 25 mins. That would be fantastic!

By the way, I found this online if anyone is interested. It converts from NEMA 6-20P to 5-15R, basically downconverts from a 240V 20A outlet to a standard 120V 15A: https://www.amazon.com/3-Prong-Receptacle-Electric-Adapter-Converter/dp/B07KQSCS3S/

 

Black and red are hots, white is neutral, bare is ground. Doesn't really matter which hot goes to which pin.

 

MVERAS,

"and installing an outdoor rated NEMA 6-20P 240V outlet."

Change this to a 5-20R outlet, then mark it with a 240V warning. The less adapters you use, the better.


Rob43

 

I am afraid to do that. People don't read warning signs.

 

Well, you can't install a -P (plug) as a source. The pins would be hot and available to be touched. That's why sources are -R (recepticle) - to the pins (sockets) are hidden inside and can't be touched accidentally.

 

OK, I hear you....

Since there will be another link in the chain, build your Pigtail well using high quality parts.

Remember that I have A LOT of informational pics in my 240v charging thread, take another look when you build.

Using the Primes 120v Charger at 240 Volts, Cost $20 !!! | PriusChat


Rob43

 

My bad.... I would never put a 6-20P as an outlet.... geez! I meant 6-20R. Thanks for pointing that out. I like to stick to the electrical code as close as possible.

 

Yes, and thank you so much for all the great info. We can continue the conversation in the other thread.

 

It wasn't mentioned, but I think that one also needs to connect the ground pin on the EVSE to a ground wire (not neutral) in the outlet.

 

Power is measured in watts or kilowatts (1000 watts). Power quantity is measured in kilowatt-hours. 1000 watts of consumption for one hour is one kw-hr. My power company charges me about 10¢ for this. Wattage is the product of voltage times amperage (times the power factor which we'll ignore here). If the voltage is doubled and the amperage is halved, exactly the same amount of power is consumed. There might be some difference in parasitic loses with the different amperage, but those are minor. If the same kw-hr amount is consumed, the voltage doesn't matter; the cost is the same.

208 volts will be from a 3 phase system, just about always an industrial or other heavy duty situation. 208 comes from any two legs of a 3 phase wye transformer. The 3 phase wye transformer will give 120 volts between the center tap and any one leg. (Transformers can be built for any desired voltages; this is just a common example.)

Just about every home system is two 120 volt legs from the power company transformer on the pole or ground mounted. The two legs are 180° out of phase, so they give 240 volts across the two legs. This is all single phase power. We rarely get exactly 120 or 240 volts. Just a minute ago I measured 119.3 volts at my house. It'll be less if my house and the neighbors use more power, but it's all close enough. Our home power panel gets the two 120 legs and the neutral from the power company and the ground is from a steel rod driven into the ground near the power panel. My 240 volt electric oven cable is connected to the two hot legs in my power panel. My 120 volt circuits are connected to either one of these hot legs and the neutral.

Wire current-carrying capacity is measured by the wire gauge--the diameter of the copper conductor. Cable voltage rating is measured by the quality and thickness of the insulation. You'll see something like 12/3 and 300v on the cable jacket. This example has 3 conductors of 12 American Wire Gauge (AWG) and insulation rated for 300 volts service.

Wiring devices (plugs, receptacles, etc.) have NEMA designations (National Electrical Manufacturer Assn.). A designator that starts with a 5 is rated at 125 volts. A 6 gets it a 250 volt rating. The next number is the amperage rating. It isn't that simple--the number of wires matters as well as the number of phases, whether it has a ground, and whether it's locking. A P suffix means plug. R means either receptacle (which is in the wall) or connector (on the end of a cord).
NEMA Plug Chart - NEMA Plug Straight Blade Reference Chart | StayOnline
https://www.stayonline.com/product-resources/nema-locking-reference-chart.asp

An option for using the Toyota charge station with 240 volts is to cut off the NEMA 5-15 plug and put on a suitable 250 volt plug like a 6-20P.

That Amazon pigtail is not what is needed to use the Toyota charge station at 240 volts. The Amazon pigtail is wired to only one hot leg, so it'll put out 120 volts. The other problem is that it uses the ground wire as the neutral--a no-no. I don't think it is good for anything.

 

This would not be high on my list of options as it permanently alters the stock EVSE, With a properly configured pigtail, you have the option of using the stock EVSE on either 120 or 240V with no changes to the EVSE.

Plus, I don't know how the electronics in the brick would react to loss of the temperature sensor in the factory 120V plug. This could likely be jumpered or fooled.