eyedrop
Posts: 30
Joined: Sun Sep 25, 2016 10:46 pm
Delivery Date: 04 Oct 2016
Leaf Number: 312554
Location: Prescott Valley, AZ

NEMA 14-50 Charge Time?

Sat May 13, 2017 3:59 pm

Suppose I get the EVSE upgrade and want to charge using NEMA 14-50 at the RV parks. About how much range will I add per hour?

For example, Ive seen people say level 1 charging will add roughly 4-5 miles of range per hour.

I often use a Blink charger that is rated at L2, 4.7Kwh. Would the 14-50 be about on par with that? What is the Kwh rating on it?

GerryAZ
Gold Member
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Joined: Mon Nov 22, 2010 6:47 pm
Delivery Date: 12 Jun 2011
Location: Phoenix, AZ

Re: NEMA 14-50 Charge Time?

Sat May 13, 2017 4:43 pm

It depends a little on the particular version of EVSE Upgrade. The first version was 12 amperes so it would be twice as fast as L1 if source is 240 volts and about 1.7 times as fast as L1 if source is 208 volts. Later versions could be upgraded to 16 amperes or 20 amperes for L2 and remained 12 amperes for L1. At 20 amperes and 240 volts, it would be about 3.3 times as fast as L1. At 16 amperes and 240 volts, it would be about 2.7 times as fast as L1. At 20 amperes and 208 volts, it would be about 2.9 times as fast as L1. At 16 amperes and 208 volts, it would be about 2.3 times as fast as L1. The above estimated rates are assuming your car has a 6 kW onboard charger. If your car has a 3.3 kW onboard charger, then the L2 rate will be about 2.5 times as fast as L1. A 20-ampere EVSE Upgrade operating at 240 volts will allow the car to charge at about the same rate (4.8 kW) as the Blink that is apparently limited to 4.7 kW.
Gerry
Silver LEAF 2011 SL rear ended (totaled) by in-attentive driver 1/4/2015 at 50,422 miles
Silver LEAF 2015 SL purchased 2/7/2015

eyedrop
Posts: 30
Joined: Sun Sep 25, 2016 10:46 pm
Delivery Date: 04 Oct 2016
Leaf Number: 312554
Location: Prescott Valley, AZ

Re: NEMA 14-50 Charge Time?

Sat May 13, 2017 4:56 pm

I see. So the limiting factor isnt so much the 240V port your connected to. Its how many amps the EVSE can pull, as well as what the onboard charger is capable of. Am I correct in assuming that most 240V ports are atleast 20 amps?

Also, suppose you have a 120V and a 240V socket, both are limited to 20 amps. Would the charge time be the same, supposing your EVSE is drawing 16 Amps, and you have the 6.6Kwh onboard charger?

eyedrop
Posts: 30
Joined: Sun Sep 25, 2016 10:46 pm
Delivery Date: 04 Oct 2016
Leaf Number: 312554
Location: Prescott Valley, AZ

Re: NEMA 14-50 Charge Time?

Sat May 13, 2017 5:02 pm

I noticed your in Phoenix. The blink charger Im speaking of is the one in Anthem. According to plugshare, it is limited to 4.7Kwh. I frequently drive to Phoenix and back from Prescott Valley on the weekends. I use Midway Nissan Chademo for most of my charging (fast and free), and always need to top off at Anthem ($5) before I head up the I17. I basically have to limit my speed and power output to make it home with 10-20% SOC. With the EVSE upgrade, I can get a charge in Cordes Jct. and not have to worry about the range or driving too slow with the cut throat I17 speeders. It will also allow me to take the back roads through wickenburg, peeples valley, kirkland, tonopah, etc...

GerryAZ
Gold Member
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Joined: Mon Nov 22, 2010 6:47 pm
Delivery Date: 12 Jun 2011
Location: Phoenix, AZ

Re: NEMA 14-50 Charge Time?

Sat May 13, 2017 5:52 pm

What year and model Leaf do you have? I am asking because the upper limit on current of the EVSE Upgrade depends upon the model year of the Nissan EVSE that is upgraded. Since you have the QC port, I am guessing that you have the 6 kW onboard charger. In that case, a 14-50 receptacle would allow your car to charge at the full 6 kW rate with a suitable EVSE at either 208 volts or 240 volts. The EVSE would need to be rated for at least 30 amperes to get the highest charging rate. The maximum you get with EVSE Upgrade depends upon the voltage (208 or 240) and the maximum current allowed which would be 12, 16, or 20 amperes depending upon the upgrade. The input power is voltage times current so here are some examples:
120 V * 12 A = 1440 W or 1.44 kW (this is L1 charging with unmodified Nissan EVSE)
240 V * 12 A = 2880 W or 2.88 kW
240 V * 16 A = 3840 W or 3.84 kW
240 V * 20 A = 4800 W or 4.8 kW
208 V * 12 A = 2496 W or 2.496 kW
208 V * 16 A = 3328 W or 3.328 kW
208 V * 20 A = 4160 W or 4.16 kW

You can see from the above table that L2 charging is at least twice as fast as L1 and even faster at higher current levels. I have used that Blink unit at the Anthem outlet mall a few times, but never paid attention to the full output current. It is nominal 208 volts and the output current is probably throttled to 24, 22, 20, or maybe even 16 amperes (Blink units were originally 30 amperes, but most have been programmed lower to minimize the risk of overheating or even melting the J1772 connector on the cable and/or car). Some Plug Share reviews say 24 amperes with voltage dropping a bit below 208 so that would yield about 4.7 kW.

To answer your question about limitations, the circuit rating is the absolute maximum and the EVSE should be set to draw no more than 80% of the circuit rating. That means that the maximum output EVSE that should be used with a 14-50 receptacle (50-ampere circuit) is 40 amperes. Your car cannot draw more than about 27 amperes at 240 volts or about 31 amperes at 208 volts so a 30-ampere EVSE would give you the fastest charging your car can handle. There is a pilot signal sent by the EVSE to the car that basically tells the car the maximum current it is allowed to draw. The later versions of EVSE Upgrade are adjustable in 1-ampere increments from 6 to 12 amperes at 120 volts and 6 to 20 (or 16) amperes at 208 or 240 volts.
Gerry
Silver LEAF 2011 SL rear ended (totaled) by in-attentive driver 1/4/2015 at 50,422 miles
Silver LEAF 2015 SL purchased 2/7/2015

Graffi
Posts: 405
Joined: Wed Nov 27, 2013 12:01 pm
Delivery Date: 06 Sep 2013
Leaf Number: 414757
Location: San Diego, CA

Re: NEMA 14-50 Charge Time?

Sat May 13, 2017 6:14 pm

eyedrop wrote:Suppose I get the EVSE upgrade and want to charge using NEMA 14-50 at the RV parks. About how much range will I add per hour?

For example, Ive seen people say level 1 charging will add roughly 4-5 miles of range per hour.

I often use a Blink charger that is rated at L2, 4.7Kwh. Would the 14-50 be about on par with that? What is the Kwh rating on it?


To give you the answer you want, first we need to know your Leaf's on-board charger capacity. If you only have the J1772 port, then you have the 3.3kw charger. If you also have the DCFC port, then you have the 6kw charger.

If you only have the 3.3kw charger then anything greater than a 16amp, 240v EVSE will not give you any faster charging speed.

If you have the DCFC charging capability, then you need a 30a, 240v EVSE to utilize the full charging speed. This gives you approximately 25 miles each hour. To run a 30a EVSE you need a 40amp circuit breaker. Anything less than a 30a EVSE will slow down the charging speed. I think the EVSE upgrade is limited to 12a, 240v. The least expensive option is the DYI Open source EVSE. There are members on this board that will put it together for you for a reasonable price.

If you want to future proof your installation, in case you end up getting a Tesla Model 3, or even future a Leaf with faster charge speed, then I would suggest having it wired with 2AWG wire to handle up to 100amps.

A NEMA 14-50 is a plug outlet for a 240v, 50amp circuit. This will support any EVSE up to 40amps. 40a * 240v = 9.6kw. This is the current limit of the single on-board charger for the Tesla. The Tesla dual charger can handle up to 72amps * 240v = 17.3kw.

The charging speed of the L3 DCFC can be as high as about 125 miles each hour, so only need to be plugged in for about 20 minutes. Some of the DCFC chargers are limited to a lower amps, so give a slower charge, but still much faster than the 25 miles each hour for the 30 amp EVSE.

The charging speed of the Tesla Supercharger is about 170 miles in 30 minutes, VERY much faster than the L3 DCFC.

I hope this helps you to understand charging speeds better.
2013 SL Metalic Slate - We LOVE our Leaf
MFG 08/13 Dlv 09/06/13 @ 10 mi
# 77 100 mile club
# 10 200 km club

2017 Tesla S 75D Pearl White
Delivered 5/16/17 @ 900 mi
Tesla Model 3 on order awaiting 200+ mile range Nissan Leaf

SageBrush
Posts: 1421
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: NEMA 14-50 Charge Time?

Sat May 13, 2017 6:24 pm

eyedrop wrote:I see. So the limiting factor isnt so much the 240V port your connected to.

The weakest (slowest) link determines the rate.

watts = volts*amps
kW = watts/1000
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

SageBrush
Posts: 1421
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: NEMA 14-50 Charge Time?

Sat May 13, 2017 6:30 pm

Graffi wrote:The charging speed of the Tesla Supercharger is about 170 miles in 30 minutes, VERY much faster than the L3 DCFC.
Perhaps in a big battery, starting from a low SoC. A ~ 50 kwh Model 3 will not have anywhere near that charging performance since the charger will taper off as the battery fills past around 60%. I'll be happy with 100 miles in 20 minutes (meaning an average 75 kW rate), starting from a low SoC. The point I am emphasizing here is that the miles gained per time is far from linear. 100 miles in 20 minutes will likely be nowhere near 200 miles in 40 minutes for a Model 3.
2013 Model 'S' with QC & rear-view camera
Bought off-lease Jan 2017 from N. California with 63.9 Ahr after 22k miles
Car is now enjoying an easy life in Colorado

eyedrop
Posts: 30
Joined: Sun Sep 25, 2016 10:46 pm
Delivery Date: 04 Oct 2016
Leaf Number: 312554
Location: Prescott Valley, AZ

Re: NEMA 14-50 Charge Time?

Sat May 13, 2017 7:24 pm

Is it possible to buy the 20amp EVSE upgrade and charge off a 110v 20amp circuit, setting the EVSE to draw 16 amps? According to my calculations, this would yield 1.9Kw. A nice little boost over standard 12A. Its easy to find 110v 20A circuits at businesses with outdoor outlets...

Its unfortunate the EVSE upgrade has a max of 20A. I wonder if they are working on a 30A version for the future? Is there a portable charging chord capable of 30A? Looks like the best Ill get with 20A is 4.8 Kwh... Which is reasonable. But in the future with higher capacity batteries, these slower L2 chargers would take eternity to charge a battery to full.

cwerdna
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Delivery Date: 28 Jul 2013
Location: SF Bay Area, CA

Re: NEMA 14-50 Charge Time?

Sat May 13, 2017 7:39 pm

eyedrop wrote:Is it possible to buy the 20amp EVSE upgrade and charge off a 110v 20amp circuit, setting the EVSE to draw 16 amps? According to my calculations, this would yield 1.9Kw. A nice little boost over standard 12A. Its easy to find 110v 20A circuits at businesses with outdoor outlets...

Its unfortunate the EVSE upgrade has a max of 20A. I wonder if they are working on a 30A version for the future? Is there a portable charging chord capable of 30A? Looks like the best Ill get with 20A is 4.8 Kwh... Which is reasonable. But in the future with higher capacity batteries, these slower L2 chargers would take eternity to charge a battery to full.

I noticed you've been sloppy with units, sometimes getting them right and sometimes not. For the above 20 amp case, you meant 4.8 kW.

kW and kWh are very different metrics. It's the same as confusing gallons with horsepower. Think of kW = horsepower, kWh = gallons. kW is a rate.

If one charges at 1 kW (or 1000 watts) for 6 hours, 6 kWh came out of the wall. If it's at 6 kW for 1 hour, it's also 6 kWh. If it's 1 watt for 6000 hours, it's also 6 kWh.

One pays for electricity at home in cents per kWh. There are a few utilities w/residential plans where they not only bill per kWh but also have demand charges, but that's rare and complicates calculations. (Demand charges aren't unusual on many commercial plans.)

24 kWh Leaf has ~21 kWh usable battery but since charging isn't 100% efficient, it takes more than 21 kWh out of the wall to fully charge a dead Leaf. viewtopic.php?p=155305#p155305 has some figures, but it was before the '13+ Leaf w/optional 6 kW on-board charger.

(BTW, 1 hp = ~0.746 kW and 1 gallon of gasoline=33.7 kWh per many .gov sites.)

As for "Is there a portable charging chord capable of 30A?", sure:
http://shop.quickchargepower.com/JESLA- ... -JESLA.htm

Search the below for ones that are 30+ amps and mention plug:
https://store.clippercreek.com/level2/level2-20-to-32
https://store.clippercreek.com/level2/level2-40-to-80

It looks like you've been ignoring several people's questions abot the max wattage of your on-board charger, as THAT can be the limiting factor. What model year and trim do you have?

It is important to understand what I pointed to at viewtopic.php?f=6&t=14728&p=332668#p332668.

If you have only the 3.x kW OBC, then level 2 EVSEs above 16 amps at 240 volts will NOT help you.

'13 blue Leaf SV w/premium package (owned)
'13 blue Leaf SV w/QC + LED & premium packages (lease over, car returned)
'06 Prius

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