Chargers and breakers and circuits, oh my!

[jonessoda]

Hey all,

I just joined your ranks a couple of days ago with a FFE. I also have a Fiat 500e at home.

Here's my situation, I'm hoping to get a little insight from everyone about my course of action for integrating the FFE into the system.

The house I live in (it's a rental, I'm active duty military, I move too much to want to buy right now) has a 100 amp main. When I moved in, I used the 40A breaker that the AC used to be on. The house AC was removed at some time in the house's life, but the breaker was still there for it. I have an AeroVironment (found here: http://www.amazon.com/AeroVironment-EV-Charger-Plug-In-cable/dp/B00AHG8XVA/ref=sr_1_4?s=automotive&ie=UTF8&qid=1409971841&sr=1-4). I wasn't too concerned about having a 100 amp main since the AC is no longer part of the house.

Now that I have two EVs at home, I'd like to add a 2nd 240v charger so I don't have to physically change which car is plugged in in the middle of the night. The 120v is slow, and I'd like to limit charging time to midnight-6 to take advantage of the lower energy rates.

I'm concerned about adding another charger with the 100A main. I could set the cars to charge at different times (0000-0300 and 0300-0600 for example). What would you do in this situation?

Another question I have. I like the charger I already have, but the thing costs $1000. I'll get another one if that's just how it is, but I was curious as to what charger you guys are using, if something different than the one I have. Should I just get another one of those and call it a day?

I tried doing research on having multiple chargers in one house, but I really couldn't find anything. I guess it's not that common. Thanks in advance for any advice you can provide!

 

[EVA]

The electricians in the group will give you all the official answers you need.

Here's my non-electrician view - you don't have enough service coming in to install two chargers. It is as simple as that. You barely have what you need for the one charger you have today.

You can't load your panel with two 240V 40 or 50 Amp circuits and then say, oh I'll just be careful to not run both at the same time. It doesn't work that way.

My personal experience. I started with an FFE. Charged it with 110V. That worked just fine for most of the time overnight. I had plenty of service to my detached garage to do that.

I purchased a Tesla. In order to get a rebate in Illinois for the installation (I didn't realize Illinois put a moratorium on the rebate a month before I did the installation), I had to do an EVSE - so I added a GE WattStation for the FFE and a Nema 10-50 outlet for the Tesla. Both would be served by two 50 Amp breakers in a subpanel in the garage.

The service into my house was 100 Amps. That was just about right for everything in my house, not including the cars. So I had to pay to have the service upgraded to 200 Amps - no way around it. There wasn't enough service for the cars. You have to count that they could each draw 50 Amps - so I had to upgrade to 200 Amps.

You have the exact same situation as I did (well you have a 500e instead, but it has the same power requirements). If you want to charge both cars at 220V and have two EVSEs or even 2 - 220V 50 amp electrical outlets - you have to upgrade your service.

You could charge one car with 110V while the other charges on 220V. That isn't a bad situation. But you can't add another charging station.

Upgrade costs for your rental, if you can even do them, wouldn't be anything like what I paid. Let's just say - the cost is north of $2,000.

I'm not sure I recommend the WattStation, other than it has beefy controls in it. The thing it big. The J1772 side of the wiring is outstanding, I love the cable compared to the Clipper Creek I saw recently. The GE is more expensive though.

 

[michael]

I have a similar issue...three electric cars.

I already had an AV EVSE hard wired. Incidentally, it is supposed to be on a 40 A circuit even though it draws 30 A max. However, I see no harm in leaving on the 30 A breaker although there is some possibility it may trip occasionally.

However, to answer your question...I installed a 20 A double breaker and converted an existing 110 V outlet to 220. Use the white wire for the second phase and install a 6-20 outlet (220 volt) to replace the existing 5-15 or 5-20 120 V output. Then I got an Aerovironment Turbo cord. This serves double duty as the second charging station at home and as a portable level 2 charger. This serves me well. There are other portable level 2 but I like the Turbo cord for its small size and usability at 120 V as well.

Even if both units charge simultaneously, you are pulling 45 A max.

I think the approach of a 220 outlet and a portable L2 charger is the cheapest way to go.

 

[davideos]

Is there a plug near the dryer for an electric dryer option? If so and it is convenient, you could get a 3.3KW charger and use the 30A plug.

 

[WattsUp]

I already had an AV EVSE hard wired. Incidentally, it is supposed to be on a 40 A circuit even though it draws 30 A max. However, I see no harm in leaving on the 30 A breaker although there is some possibility it may trip occasionally.

It's not about the breaker, it's about the wiring.

It might seem to make sense, but you're not actually supposed to run a "continuous load" of X amps on a circuit with wiring capable of exactly X amps. For safety reasons, you're actually only supposed to run a continuous load of 80% of the wiring's maximum rating. This provides a margin of safety if anything is not quite up to spec. This is all according to the National Electrical Code, which most municipalities adopt.

So, for a circuit with wiring capable of carrying 30A, the maximum continuous load (without violating the NEC) would be 24A.

 

[jonessoda]

Oops. The breaker that the AC used to be on is a 40A, I wrote that incorrectly in my first post. I knew it had to be 40A for a 30A load, that's why I was happy to see the 40A breaker still in there from the old AC system.

The dryer is in the garage, but it's electric, so the outlet is taken.

 

[davideos]

Unless you are using the dryer from midnight to 6am, I think you may have found a viable solution. Perhaps you can craft or purchase a 2 to 1 power strip, for lack of a better word. Just an option.

 

[jonessoda]

However, to answer your question...I installed a 20 A double breaker and converted an existing 110 V outlet to 220. Use the white wire for the second phase and install a 6-20 outlet (220 volt) to replace the existing 5-15 or 5-20 120 V output. Then I got an Aerovironment Turbo cord. This serves double duty as the second charging station at home and as a portable level 2 charger. This serves me well. There are other portable level 2 but I like the Turbo cord for its small size and usability at 120 V as well.

This might just be the way to go. There are actually a ridiculous number of 110v outlets in this garage. I should trace them and see what the deal is, there is no way this many outlets are coming from one 15A breaker. I like the idea of that turbo cable thing too, especially since I already have a wall mounted charger. It would be one less thing to mount on the wall, and I could use it as a portable in case I had access to 220v somewhere else (doubtful, though, these aren't really road trip cars).

Thanks for the input, I'm definitely going to investigate this avenue.

Unless you are using the dryer from midnight to 6am, I think you may have found a viable solution. Perhaps you can craft or purchase a 2 to 1 power strip, for lack of a better word. Just an option.

Unfortunately, it's on the wrong side of the garage. The car has to stay in the spot that it is in, so I don't think I can get away with using the dryer outlet. I had actually considered trying to make it work when I first moved in with the charger I already have, but the logistics are a little iffy.

 

[hybridbear]

I don't see why you couldn't install a second EVSE on the same circuit as long as you make sure the cars won't charge at the same time. You could use a timer with each EVSE to limit when it has power to ensure that they don't both have power at the same time.

I'm not an electrician, but this seems logically like it should work.

 

[jeffand]

Charging the car in 4 or 8 hour doesn't matter if you are charging overnight. Using a two TurboCords setup maybe an option.

You will need the following parts
A 50 amp electric range cord.

One cord grip for the electric range cord.
Small circuit breaker box that can acomidate two double pole circuit breakers.

Two 20 amp double pole circuit breakers.

Two nema 6-20 sockets.

Socket openings could be cut into the sides of the circuit breaker box, or an external jnction box could be used.
Two TurboCords.

The two TurboCords will draw a combined maximum current of 32 amps.
All these product can be ordered from Home Depot.

 

[triangles]

With 100A service you should be able to safely charge both simultaneously. I don't know what the charging rates are for the Fiat so for this example I'm assuming they are the same as the FFE. The FFE charges at a maximum rate of 6.6KW (27.5A@240V). By doubling this (two cars) you're only pulling 55A or slightly more than half your house's capacity. A 20A (4.8kW) EVSE should charge the car in about 5 hours (at least by my rough calculations) which keeps things well withing your off peak time window. If your land lord permits and you feel like the extra work, you could remove two 120V breakers and wire in a new 240V circuit that is of course assuming there isn't already empty space for a 240 breaker.

I'm concerned about adding another charger with the 100A main. I could set the cars to charge at different times (0000-0300 and 0300-0600 for example). What would you do in this situation?

Another question I have. I like the charger I already have, but the thing costs $1000. I'll get another one if that's just how it is, but I was curious as to what charger you guys are using, if something different than the one I have. Should I just get another one of those and call it a day?

Personally In your situation I would look for an EVSE around 20A (4.8Kw) and use a long enough cord to reach your dryer plug and just switch between the two or make your own splitter for that outlet. It should go without saying that you'd use your dryer or the EVSE, not both! For cost savings I would get a JuiceBox. They are much cheaper than the EVSE you have and you can likely order one with a long enough cord to reach your dryer plug. Additionally they have an adjustment that you can sent your max charge rate to. If you're not comfortable messing with electronics you could probably have them preset this maximum for you or if you spend a little extra money for the premium JuiceBox it has a LCD screen and one of the options on this you can set your maximum current draw.

Edit: I missed it but the Hydra mentioned above sounds like the ticket!