dumb question about quick charging

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RustyShackleford

Well-known member
Joined
Jun 24, 2019
Messages
157
Location
central NC
I've looked at the manual honest ...

Our new 2018 Leaf SV has the quick charge port; great ! But we just went to a Charge Point station and the equipment there plugs into the smaller J1772 port on the car, not the big quick-charge port. Will it still charge at the quick-charge rate (1hr or so) or will it only charge at the Level2 rate (8 hours for the 40kwh battery) ? I'm thinking the latter - meaning that just because a charging station is publicly (and often freely) available does not mean it's any faster than Level2 (that is, it is not guaranteed to be Level 3).
 
It will charge at the L2 rate, which can vary from one EVSE to another and also often depends on whether or not there is one or two cars plugged into the EVSE, if it has 2 plugs on one pole.
 
You need to find a DC Fast charger that has a Chademo connector, not the CCS or Combo connector that looks like a J1772 connector with two larger pins at the bottom. Are there any eVgo stations near you? They have some of each connector, but you'll be able to see a Chademo connector at their sites...
 
Thanks for being gentle, guys. One's initial impression is that all public charging stations are capable of quick charging. No. And it sounds like one of these public L2 stations may not even provide the full 6.6kw rate, especially if two cars are connected.
 
RustyShackleford said:
Thanks for being gentle, guys. One's initial impression is that all public charging stations are capable of quick charging. No. And it sounds like one of these public L2 stations may not even provide the full 6.6kw rate, especially if two cars are connected.
Most public J1772 stations provide 30a @ 208 volts for 6.2 kW. Sometimes they will be a full 6.6kW, a few will be limited to 16a or 24a. A very few will be higher amperages like 40a or 70a. There may be a few that share power like you suggest, but most stations with two plugs supply the full power to both. Plugshare.com is the place (and app) that's best for both finding public charging as getting these kinds of details about a site. You also get user feedback about reliability.
 
Check out plugshare.com
The locations specify the charging options, and you can filter by charging type.
 
The vast majority of public charging stations are in fact Level 2, not DCFC. You can see this on PlugShare, where DCFC stations are marked in orange, and others are marked in green. (Turn off "Wall", which are Level 1, for best results -- although the effect is even more pronounced if you don't.)

DCFC equipment is an order of magnitude more expensive than Level 2 EVSEs to install and run, hence its relative rarity.
 
@Rusty, there is another factor to the CHAdeMO-vs.-J1772 (L3 vs. L2) issue: type of current. The wall plug and L2 charging stations are all alternating current suppliers. The vehicle’s J1772 port goes to a device in the vehicle that converts it to direct current which in turn charges the battery. So L1/L2 charges are limited by the vehicle itself and how much current it is designed to accept. This limit has changed over time and model year.

L3 charging stations and the larger port on your vehicle are all direct current and the conversion device in the car is bypassed so the juice is going directly to the battery. Now the amperage/voltage limitation is at the charging station primarily vs. the car in the other scenario.

Lastly the L2/L1 charging stations are all single phase, likely how your home is wired. L3 stations are three phase, more typical of commercial installations and far, far more expensive. The charging station equipment is also more expensive to handle the much-increased current flow safely. For example, you can likely install a 240v charging station in your home for well under $1000 today. Our city installed an L3 station and the costs NOT including permitting and already on city-owned property was just a bit over $25,000. While that was three years ago and included the add-ons for accepting credit cards, installing an L3 station is not an inexpensive proposition.
 
SalisburySam said:
L3 charging stations and the larger port on your vehicle are all direct current and the conversion device in the car is bypassed so the juice is going directly to the battery. Now the amperage/voltage limitation is at the charging station primarily vs. the car in the other scenario.


The vehicle's BMS does the primary control of the charging current.

SalisburySam said:
Lastly the L2/L1 charging stations are all single phase, likely how your home is wired.

Most all homes are wired for two phase (~ 220V for some applications), and that provides the ability to develop the higher L2 charging power.
 
lorenfb said:
SalisburySam said:
SalisburySam said:
Lastly the L2/L1 charging stations are all single phase, likely how your home is wired.

Most all homes are wired for two phase (~ 220V for some applications), and that provides the ability to develop the higher L2 charging power.
Er, no. Two phase hasn't been in use for any but very specialized applications in many decades. Home current is usually a transformer at a telephone pole or on the ground that reduces transmission voltages of 12kv-14kv to two 120v lines and a neutral that connect to your home's meter.
This is the service entrance. These go through the home's meter and to the main load center for the home. This is always where, by code, neutral and grounds may be bonded. This is a single phase system, sometimes called a split phase system because of the two 120v lines. 240v appliances (dryers, electric stoves, ovens, etc.) use two 120v hot lines bridging the current within the device to 240v. This does not make it a two-phase system.
 
lorenfb said:
SalisburySam said:
L3 charging stations and the larger port on your vehicle are all direct current and the conversion device in the car is bypassed so the juice is going directly to the battery. Now the amperage/voltage limitation is at the charging station primarily vs. the car in the other scenario.


The vehicle's BMS does the primary control of the charging current.
You're both right. The charging station limits the charging current, but the car determines what it actually is, subject to that limit.

SalisburySam said:
Lastly the L2/L1 charging stations are all single phase, likely how your home is wired.

Most all homes are wired for two phase (~ 220V for some applications), and that provides the ability to develop the higher L2 charging power.
Nope, the wiring of most houses is single-phase, or split phase. It's confusing because there are two lines that are 180 degrees out of phase with each other. From wiki "The two 120 V AC lines are supplied to the premises from a transformer with a 240 V AC secondary winding which has a center tap connected to ground. This results in two 120 V AC line voltages which are out of phase by 180 degrees with each other. The system neutral conductor is connected to ground at the transformer center tap. 240 V AC can be obtained by connecting the load between the two 120 V AC lines."
 
RustyShackleford said:
lorenfb said:
SalisburySam said:
L3 charging stations and the larger port on your vehicle are all direct current and the conversion device in the car is bypassed so the juice is going directly to the battery. Now the amperage/voltage limitation is at the charging station primarily vs. the car in the other scenario.


The vehicle's BMS does the primary control of the charging current.
You're both right. The charging station limits the charging current, but the car determines what it actually is, subject to that limit.

SalisburySam said:
Lastly the L2/L1 charging stations are all single phase, likely how your home is wired.

Most all homes are wired for two phase (~ 220V for some applications), and that provides the ability to develop the higher L2 charging power.
Nope, the wiring of most houses is single-phase, or split phase. It's confusing because there are two lines that are 180 degrees out of phase with each other. From wiki "The two 120 V AC lines are supplied to the premises from a transformer with a 240 V AC secondary winding which has a center tap connected to ground. This results in two 120 V AC line voltages which are out of phase by 180 degrees with each other. The system neutral conductor is connected to ground at the transformer center tap. 240 V AC can be obtained by connecting the load between the two 120 V AC lines."

Re-read what was written. They all say the same thing, or should we parse each word? Remember, phase describes angle!
 
lorenfb said:
Remember, phase describes angle!
Correct!
lorenfb said:
Re-read what was written. They all say the same thing, or should we parse each word?
Two phase systems have a 90° difference. Split-phase is 180° difference. They are not the same thing.
https://en.wikipedia.org/wiki/Two-phase_electric_power
https://en.wikipedia.org/wiki/Split-phase_electric_power
 
jlv said:
lorenfb said:
Remember, phase describes angle!
Correct!
lorenfb said:
Re-read what was written. They all say the same thing, or should we parse each word?
Two phase systems have a 90° difference. Split-phase is 180° difference. They are not the same thing.
https://en.wikipedia.org/wiki/Two-phase_electric_power
https://en.wikipedia.org/wiki/Split-phase_electric_power

That's the best you can contribute, parsing words?
 
lorenfb said:
That's the best you can contribute, parsing words?
You're wrong, period. In science/engineering, specific words are very important, such as the difference between 90 degrees and 180 degrees. I don't want to "pull rank", but I am imminently qualified on electrical matters.
 
RustyShackleford said:
lorenfb said:
That's the best you can contribute, parsing words?
You're wrong, period. In science/engineering, specific words are very important, such as the difference between 90 degrees and 180 degrees. I don't want to "pull rank", but I am imminently qualified on electrical matters.

Get a life!


RustyShackleford said:
Our new 2018 Leaf SV has the quick charge port; great ! But we just went to a Charge Point station and the equipment there plugs into the smaller J1772 port on the car, not the big quick-charge port. Will it still charge at the quick-charge rate (1hr or so) or will it only charge at the Level2 rate (8 hours for the 40kwh battery) ? I'm thinking the latter - meaning that just because a charging station is publicly (and often freely) available does not mean it's any faster than Level2 (that is, it is not guaranteed to be Level 3).

RustyShackleford said:
So Level 3 must bypass the car's on -board charger, since it can pump an order of magnitude more juice into the car than it can accept via Level 2, right ? (If you have the quick-charge port).

RustyShackleford said:
So there's no such thing as a charging cable that would only pull 24 amps (and so be ok w/ 30amp circuit)

RustyShackleford said:
By code you will need at least 40 amps to power the 2018-2019 Nissan 120/240v.

Stick to fixing portable radios.
 
lorenfb said:
Stick to fixing portable radios.
Uh yeah, that was cute the way you posted all the questions I've asked in the last week or so. It's called a learning curve - I've never owned or even thought much about an EV before. Yeah, I'll admit it: you know more about EVs than I do (for now at least). I don't think it makes me stupid. OTOH, understanding the difference between one-phase and three-phase power is a pretty fundamental concept in electrical engineering. And yet you continue to make erroneous claims, in the face of direct contradiction from me, and one or two other guys here.

Here's a tip for you: Admitting you are wrong makes you more of a man, not less of one. Notice how I admitted you know more about EVs than I do ? And yet you bothered to grab a bunch of my posts from the last week to try to convince folks you're right. So, in your words:
Get a life!
 
Homes in the US are generally 240v, split phase. This is single phase service. Commercial or industrial may have three phase.

No two phase. Fun to argue though because 'phase' has two different meanings that apply. Wiki explains it better than I can.
 
smkettner said:
Homes in the US are generally 240v, split phase. This is single phase service. Commercial or industrial may have three phase.

No two phase. Fun to argue though because 'phase' has two different meanings that apply. Wiki explains it better than I can.

Probably the easiest way to explain it is that if you "split" something, there is only one of it. You then end up with two halves that together still add up to just one.
 
smkettner said:
Homes in the US are generally 240v, split phase. This is single phase service. Commercial or industrial may have three phase.

No two phase. Fun to argue though because 'phase' has two different meanings that apply. Wiki explains it better than I can.

There are two phases or a split phase for those that like to parse words and need to refer to wiki
i.e. each line is 180 degrees out of phase (an angle):

Vphase1 = Vrms x sin (A)
Vphase2 = Vrms x sin (A+180)

Vphase3 = Vphase1 - Vphase2 (any phase other than 180 degrees results in less than 240V RMS)
A three phase system has three phases, each 120 degrees out-of-phase with each phase.

And for those that must always refer to wiki; https://en.wikipedia.org/wiki/Phase_(waves)
In physics and mathematics, the phase of a periodic function F of some real variable t is the relative value of that variable within the span of each full period.

Should we continue parsing terms?
 
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