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Joined
Nov 18, 2009
Messages
15
Location
Nashville, TN
Hi!

My name is Jessica and I work with Nissan. We're excited about the launch of our 100% electric LEAF and are eager to share with you about it.

Thanks for getting involved on this forum already! We looking forward to joining these conversations. Please feel free to ask questions and share feedback.

As you may know, our main Web site is accessible here: http://www.nissanusa.com/leaf. Feel free to sign-up there to be on the emails for the latest news, information and tour stops for our Nissan LEAF Zero Emissions Tour.

We're also online on -

Facebook:
http://www.facebook.com/nissanleaf

Twitter:
http://www.twitter.com/nissanevs

Thanks!
 
Dear Jessica,
Your appearance on this forum could be an encouraging thing, however, I don't want to be rude but the official Nissan website that you gave us hasn't been much helpful at all.
We are talking about http://www.nissanusa.com/leaf . They promise to answer your question but they only answer questions that they want to or no replies altogether.
Sorry, but some people on this forum have already agreed that the official page suck too much...
So, our best hope to receive some kind of attention is this forum.
Therefore, I'm very glad to see you here, please don't forget us and drop by often if you can, read the posts and reply to them please.
We are all excited about the Leaf and can't wait to buy one. (my wife and I being crazy about this car lol). God speed.
 
Hi Jessica, welcome to the Nissan Leaf forum! Thanks for being involved and filling us in on the latest and greatest!
 
Welcome Jessica!

I just signed up, and this is one of the main reasons I did.

I love the idea of Nissan having a presence on this forum, so we can ask questions about the Leaf and get an educated answer!

You'll be hearing questions from me soon, i'm sure!
 
JesswithNissan said:
Hi!

My name is Jessica and I work with Nissan. We're excited about the launch of our 100% electric LEAF and are eager to share with you about it.

Thanks for getting involved on this forum already! We looking forward to joining these conversations. Please feel free to ask questions and share feedback.

< cut >

Hello Jessica, where are you??? We miss your presence on the forum. Please come back soon !!!
 
Hello Jess....

I have a question and a suggestion...I will ask the question here...I will put the suggestion down in the suggestion subforum (what a novel concept :) )...

Question:

If somebody is going to be doing some electrical work on their garage this summer and wanted to run a nice big piece of copper wire from the circuit breaker box to the garage for future use with the LEAF, what would be the best, correct, biggest wire they should use?

30 amp? 40 amp? 50 amp?

Thanks

Gavin
 
IMHO, no matter what Nissan is limited to, I'd go with "as big as you can afford".

That wire will last many decades. Think of the future.

My thought process is that, 30 years from now, when consumer-level electric vehicles can handle a full day's driving on a single charge, if you want to be able to refill a reasonably efficient EV overnight, you'd want 80A or so.
 
Don't forget, you might even want to make more than one run - as you'll likely want more than one EV in the future. :)

Minimum copper wire gauge based on ampacity (assuming standard NM-B 60*C rated wire):

15A 14 gauge
20A 12 gauge
30A 10 gauge
40A 8 gauge
55A 6 gauge
70A 4 gauge
85A 3 gauge

Data taken from here: http://www.cerrowire.com/default.aspx?id=46

I would recommend running one gauge bigger than necessary, especially if the run is of any significant length to minimize voltage drop.
 
Two car garage...so I should do two runs....Very smart. Thanks

Sadly I wouldn't have thought of that till too late.

Do some of the home charges handle two lines/cars at once?

So either two 6 gauge lines, or one 3 gauge line (if to one home charger that can charge two cars at one time) should keep me at least somewhat future proof.

Gavin
 
Gavin,

you should just put a 100-150A subpanel in the garage, then breakers/wire can be run off that panel to the EV charger(s)

of course it depends on the size of the service in your house, you can't run a 150A subpanel of a 100A main panel :)
 
Very interesting discussion. I had been discussing 8 gauge with my electrician. Reading through Karen, dees and mitch's posts, I may well go higher. Thank you. Steve
 
mitch672 said:
Gavin,

you should just put a 100-150A subpanel in the garage, then breakers/wire can be run off that panel to the EV charger(s)

of course it depends on the size of the service in your house, you can't run a 150A subpanel of a 100A main panel :)

Ha...yes, just last year redid the main panel (the old one was 45 years old). We were adding a pool to the back and needed some more amperage and also wanted to move the panel from the back of the house to the side. Our old box was only 100A. Our new box is 200A. So we have some power to spare. Though not 150A :) .

We do have a small subpanel in the garage to run the air and heat and some other stuff...I think it only has a 30A line running to it...I could make that bigger and rerun a bigger line to it. Maybe that should get a 3 gauge wire? Having 85A to the garage subpanel should allow for 50A to a car charger and still leave 30A for the air and heat and washer and such.

Gavin
 
Wow Gavin,
All I know is that I sure don't want to be the guy who wrestles a 3 gauge line from my panel to the garage and that is a short run! Very interesting....all sorts of things for me to think about here....thanks for the original question....
Steve
 
sjfotos said:
Wow Gavin,
All I know is that I sure don't want to be the guy who wrestles a 3 gauge line from my panel to the garage and that is a short run! Very interesting....all sorts of things for me to think about here....thanks for the original question....
Steve

Steve, It's worse than that, you have at least (3) conductors, netural, hot, hot, and in some cases the electrical inspector will make you run a #8 ground as well (bonding), you would need at least a 2" conduit (bigger is better), and a cable puller, you can't real do it by hand.

I was thinking about this very issue, and was thinking of asking if my utility is going to have "EV charging rates" (off peak/time of day), and perhaps just put in another meter to a new panel in the garage, just for use for the EV(s) chargers, there is another "customer" monthly charge, however if the EV/TOD rate may be low enough to offset that...
 
The electrical wiring codes are ... sometimes strange. And all wiring should be permitted, at least before connection, I suspect. And, the local codes can vary.

To avoid having to tear something out, I suggest getting professional approval of your design. Bigger might seem better, but is not always allowed.

I had to remove the 150-amp input breaker on my 150 amp service box, and replace it with a 110-amp breaker when I added a 40-amp breaker to connect my 7kW PV system into the service box. So, now at night, I can only draw 110 amps, not 150! The reason, a 150-amp "rated" metal "service" box is not allowed to have more "possible" input than the box's rating.

And, if I wanted to put in a higher-capacity service box (even if I stayed with the original 150-amp breaker), SDG&E said that they would require me to trench out to the street, approx 28" deep and lay in a conduit. They would inspect and pull in the new wires required for the (potentially) larger demand. The trench would have to cross all the other utilities except water (gas, phone, cable, and the existing electrical conduit).
 
garygid said:
I had to remove the 150-amp input breaker on my 150 amp service box, and replace it with a 110-amp breaker when I added a 40-amp breaker to connect my 7kW PV system into the service box. So, now at night, I can only draw 110 amps, not 150! The reason, a 150-amp "rated" metal "service" box is not allowed to have more "possible" input than the box's rating.
Warning - getting OT here!

Actually, with PV there is a 20% exception - you are allowed to exceed the busbar in your panel (which typically has the same rating as the panel) by 20% when backfeeding power for residential applications. This is explicitly allowed by the NEC. The only caveat is that the breaker should be located at the opposite end of the bar as the main breaker. This is to avoid overloading any one section of the busbar. The theory is that if you short out your busbar, no section of the bar will see more than the busbar rating.

So if you have a 150A panel/breaker, you can use a 30A breaker to feed in your solar power. Of course, since you need a 40A breaker for a 7kW PV system, that still means you have to downsize your main breaker, but you should only have to downsize it by 10A to 140A.

150A * 120% = 180A - 40A = 140A. 140A breakers aren't common, but 125A breakers are so you would be safely able to get another 15A from the electric company if you wanted.

garygid said:
And, if I wanted to put in a higher-capacity service box (even if I stayed with the original 150-amp breaker), SDG&E said that they would require me to trench out to the street, approx 28" deep and lay in a conduit. They would inspect and pull in the new wires required for the (potentially) larger demand. The trench would have to cross all the other utilities except water (gas, phone, cable, and the existing electrical conduit).
I ran into that issue, too with my house. I currently have a 100A panel and the main feed wires are only rated to 125A. Upgrading to 200A service means running new wires (which are buried) up to the latest code in a trench to the street. At the street, the trench actually needed to be 3" deep thanks to the handhole it would be connecting to. There are all sorts of crazy requirements for the trench - only 2 90* bends allowed, 2" PVC conduit, feed entrance can't be within 3" of the gas meter (and right now my gas meter is right under the main service panel), has to be filled with proper material, etc.

Quote I got would end up being like $6,000 to do the work. Ouch! It's the only time I wish I had overhead lines - upgrading those are easy in comparison.

I suspect that these sorts of issues will be fairly common when people start getting pre-checks done to see what it will take to get a 240V 20-40A charger hooked up.

My breaker box is full after adding my 3.24 kW PV system. Hopefully I can get away with a 125A main service feed to get the charger. Actually, if I can get a 200A box with a 125A main breaker, then I'll have plenty of room to upgrade my PV system in the future. :) 200A * 120% = 240A - 125A = 115A of PV power - about a 22 kW system. :) I'll run out of roof space long before I get anywhere close to that. :)
 
Thanks, I did not know about the 20% exception for PV, or how to calculate it.
I will check with the local building dept to see if it applies here.
Another 30 amps would be great.

Since I am also out of room for breakers, I might put in a sub-panel right on the back of the in-wall, exterior-facing main panel, and move some breakers into the sub-panel.

Is there a limit on the sum of the load-breakers in a box?
Does not seem to be.
 
So back to the subject... I hate to see a whole forum section built around company participation... but with no participation. :(
 
I would give Jess a bit of slack on that point. Remember that this site has just recently had a big jump in posting and thread creation. I'm sure Jess tended to just peek in from time to time to see if anything needed addressing. Now she really could look in each day and find new questions to look into...heck she could check a few times a day like I do...but that is a new development, and I'm sure she needs some time to realize that and make the proper adjustments.

Also, I think this is an unofficial LEAF site, so any contributions by actually Nissan staff is a nice bonus. It will be great if Nissan is a common posting presence here, but most sites don't get that. Nissan would be wise though to post here often...it helps them as much as us. Helping to shift and structure the conversation is a good thing.

Gavin
 
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