Adding home EV charging ?s

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EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
I didn't read the entire thread (a lot of quick interest from the crowd!), but your "no garage" comment made me think of a car port. I read that a solar car port benefits from the 26% tax credit. I'm pondering the feasibility of this for the house, even though I don't yet have an EV.
We have too many trees ( half aren’t mine) for solar. It will parked in a driveway. I have keep trying /wanting to make solar an option is just isn’t a good one for us
 

EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
Would you feel comfortable running a 20A 240V gfci outlet on 12-2 +ground and not running a neutral?

The wire is already run from the sub panel.
 

woodgeek

Minister of Fire
Jan 27, 2008
4,680
SE PA
Would you feel comfortable running a 20A 240V gfci outlet on 12-2 +ground and not running a neutral?

The wire is already run from the sub panel.
I wired up a friends outlet like that for his LEAF. He already had three wires (2+GND) running 120V 20A, and I just changed the breaker and the outlet. Voila: 3.8 kW.

The EVSE plugging into doesn't have a neutral. Its a 240V three prong plug.
 
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woodgeek

Minister of Fire
Jan 27, 2008
4,680
SE PA
Would you feel comfortable running a 20A 240V gfci outlet on 12-2 +ground and not running a neutral?

The wire is already run from the sub panel.
Deets:

The EVSE (like I linked to above) are dual voltage 120V/240V units with a 15A 120V male plug on them. Designed to work at 16A and 240V. I did NOT want to put a 15A 120V outlet on the outside of a house that was wired for 240V, bc obv someone could come up and plug in a hedge trimmer and blow it up (or worse). Soooo. I installed the correct NEMA outlet for a 240V and 20 A service. I then wired up an adapter for the EVSE to convert the standard 120V male plug to a 240V 20A male plug. And ziptied the adapter to the EVSE.
 

EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
Quick update.

EV delivery should be in a day or two. I’m 75% certain it has transferrable free lifetime supercharging. If that’s the case the plan is to charge 120V at home and hit up the super charging when I can or need too. If it’s not free, 20 amp GFCI 240 breaker and and a 6-20R receptacle. Is the cheapest way to charge using the mobile charger.

I watched all the you tube videos on how to cram car seats in to an EV if you are a family of 7. It’s just like wood stove Tetris except you can’t leave one of them out to load next time.

Evan
 
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RustyShackleford

Minister of Fire
Jan 6, 2009
1,133
NC
I'm a little confused by this talk of a 20amp 240vac outlet. Our Leaf ("the Ford Escort of EVs") can make use of 32amps of charging current, so I'm surprised there's EVs that use that much less. Even if there are, there's "future proofing"; that's why I installed a 40amp charger (on a 50 amp circuit).

Also, having not read whole thread, I'm not crazy about the idea of an outlet, as opposed to a dedicated charger (that is hardwired and has a J1772 plug), IF it's an outside environment, so you might be standing on wet ground, in the rain, plugging the thing in.
 

EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
I'm a little confused by this talk of a 20amp 240vac outlet. Our Leaf ("the Ford Escort of EVs") can make use of 32amps of charging current, so I'm surprised there's EVs that use that much less. Even if there are, there's "future proofing"; that's why I installed a 40amp charger (on a 50 amp circuit).

Also, having not read whole thread, I'm not crazy about the idea of an outlet, as opposed to a dedicated charger (that is hardwired and has a J1772 plug), IF it's an outside environment, so you might be standing on wet ground, in the rain, plugging the thing in.
#12 2+ ground is already run. Only need 8’ to get to the exterior wall of the house. Gfci is a must for me. It’s not that the EV can’t charge faster it’s in busy and cheap just need something ASAP. On closer inspection today while doing some other electrical work I realized my main 200 panel is or is very close to not being able to accommodate another 60-90amps. 70A and 90A sub panels, Ac, 60 A heat strip, 60 amp steam shower the. All the 240 appliances. Open slots but didn’t do load calc.

I totally agree a new high amp circuit is the best way. Just not ready to head down that path yet. What’s the bare minimum I need. 180 miles a week. 3 miles per hour charge. Needs 60 hours a week plugged in to 120v. That’s doable. 7 pm-7am 5 days a week. Doesn’t work out swap out to a 240v, 2+1 receptacle and 240v gfci breaker. 120$ fix. Or get a real charger 600$.

If it has free charging I live 10 minutes from the super charging station and drive by it regularly with extra time in my schedule 3-4 times a week. None Of this might matter.
 
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peakbagger

Minister of Fire
Jul 11, 2008
7,455
Northern NH
Home charging is a can of worms, there is a SAE standard for Level 1 and Level 2 charge plugs but on board equipment for EVs and PHEVs are not standardized. My Toyota PHEV is limited to an onboard 3300 KW AC to DC Converter. Most of the world uses 240 volt house current so just like computers and a lot of equipment is insulated and designed for 240 volt AC input. The US is a special case which uses 120VAC. In many cases the cord is exactly the same as 240 cord except that there is plug adaptor pig tale that plugs into a standard 120 VAC outlet. There is no need for a box on the wall, the cord that came with the car is designed to plug into a standard wall outlet. The charger senses the voltage and only draws 12 amps as a typical double straight blade outlet is fed from a 15 AMP breaker. If the cord plugs into the wall, it has to plug into a GCFI outlet if its in a potentially wet area like a garage. This is called a Level 1 charger. so 12 AMPs multiplied by 120 volts is charge rate of 1440 watt hours or 1.44KWh. Some companies sell level 1 UL rated chargers that are permanently wired into the wall and may be fed by a 20 AMP circuit (or larger), so they can draw 16.6 amps or 2 KWhr. They usually have wireless capability to be turned on and off remotely. If you are in area that has off peak rates its one way to take advantage of them. My Toyota can do the same thing by a Toyota Ap (which has a monthly fee).

Various folks and companies figured out that most of these EVs were designed for 240 Volts so they came up with level 2 chargers. They operate at 240 volts. This is usually where the AC to DC converter capacity comes into play. On my Toyota, it can only handle 3300 watts so divide by 240Volts and the most amperage it can draw is 13.75 amps which is above the rated continuous load on 15 Amp circuit, so I bumped up to a 20 Amp circuit. I happen to have a 50 Amp welding outlet near my garage panel so it might make sense to just plug into the welding outlet, but the welding outlet does not have a GFI breaker. Just because the plug is rated for 50 Amp doesn't mean I charge any faster as the AC to DC converter is the limiting factor. For another 5 to 10 grand if I bought the deluxe version Prime the AC to DC converter is 6600 watts. In my case I bought a UL rated 240 Volt charge cord and plugged it into a 240 VAC 20 Amp outlet fed from a GFCI breaker. My battery pack is 18.1 KWh so I can charge up the battery from flat in about 5.4 hours. Some folks have just bastardized the regular 120 VAC charge cord by building or buying an illegal 120VAC to 240VAC plug adaptor. Unfortunately most of the charge cords are only listed for 120 VAC (even though the same charge cord with different plug is used elsewhere on 240 VAC). The difference is if you burn your garage down, its unlisted equipment if used at 240 VAC. Note that the actual plugs that plug into the outlet have temperature sensors in them to detect if there is a problem with the internals of the wall plug. If a bootleg adaptor is used, the sensor will not detect a problem with the outlet as it will be a couple of inches away. The alternative is buy the more expensive UL rated hardwired charger hooked to a dedicated circuit. It has a GFCI inside.

Tesla sells a home charger that plugs into a 50 amp dryer plug. Some of the installations skipped the GFCI but the codes have changed that they now need an outlet fed by GFCI.

There is also the case where if someone is plugging into a real outdoor outlet without a roof over it that the outlet has to be equipped with a rated cover designed to shield the connected plug in the outlet. The old fashioned hinged cover that shields the outlet from rain are not adequate as with some thing plugged into it, its not waterproof.

Its a moving target and even electricians are confused.
 
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NoGoodAtScreenNames

Feeling the Heat
Sep 16, 2015
449
Massachusetts
Not to hijack the thread, but I have a 20 amp / 240 volt non GFCI outlet in my garage that I plug my portable charger into for our Prius and soon to be RAV4 Prime. It’s not out in the weather but the floor often gets wet in the garage from melting snow from the cars. The charger has a GFCI built into it and it is always plugged in. Does the breaker also need to be GFCI if it’s in the plug? I suppose if something went bad before the charger we wouldn’t have the protection, but I’ve also read that doubling up GFCIs in series can be problematic.
 

peakbagger

Minister of Fire
Jul 11, 2008
7,455
Northern NH
IMO (and I am not an electrician) is that your installation is grandfathered but not in compliance with current code which was changed to include all outdoor plugs including 240volt. If it was hard wired into the panel with no plug and outlet that you are covered.

Good pick on the Prime ;) . If its a SE, the 20 Amp plug is fine but if you are buying the XE or XLE and want faster charging you can go with higher amperage circuit since you have the larger AC to DC converter. I am active on the Rav 4 Prime forum. Get ready for the inevitable cold weather fog horn mystery unless they have solved it and the "how do I quiet the choir of out of tune angels" question. Other than those annoyances, I am very impressed at the overall package. GIve me a PM if you want to talk factory tow hitches as I installed mine on my own.
 

EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
Not to hijack the thread, but I have a 20 amp / 240 volt non GFCI outlet in my garage that I plug my portable charger into for our Prius and soon to be RAV4 Prime. It’s not out in the weather but the floor often gets wet in the garage from melting snow from the cars. The charger has a GFCI built into it and it is always plugged in. Does the breaker also need to be GFCI if it’s in the plug? I suppose if something went bad before the charger we wouldn’t have the protection, but I’ve also read that doubling up GFCIs in series can be problematic.
I’d be ok with that. I would consider that inline gfci. I decided that whenever I do any work I will do my best to bring up to current code. I was unable to find any 240 gfci receptacles. That leaves the only option as a two pole gfci breaker. 100$ and 15 minutes. Moving into period of my life where 100$ on very small extra margin makes sense and doesn’t seem too costly.
 

woodgeek

Minister of Fire
Jan 27, 2008
4,680
SE PA
Good advice above. Some comments:

1. The plan to use 'free' superchargers and charge 120V at home will get really old, really fast. Even if the supercharger is fast, sitting there for 30+ minutes just to save a few bucks will get annoying. And how many times do you need to wake up to a quarter full Tesla before you give up on 120V? L2 (240V) home charging is great, just plug it in (like your phone) and its always ready to go. And the price is sooo much less than gas, esp given the higher eff (mi/kWh) of the Teslas.

2. About the outside/rain factor. The entire POINT of the EVSE, instead of just plugging in your EV, is safety. The contacts on the EV connector are DEAD until after its plugged in AND a microcontroller has determined that the ground contact is made and a suitable handshake exists (i.e. its plugged into an EV, not your wet fingers). So there is no reason you can't stand in a puddle in the rain in your bare feet and lick your Tesla connector to see what it taste's like. Totally safe. And a level BEYOND the safety GFI provides. You are putting in GFI to make codes happy, not bc of any safety factor.

So this is where the plug comes it. The plug/outlet is the only unsafe part of this plan, esp re weather. I would put the outlet in an 'in service' weather box. The in service box has a notch such that the box can be closed with the plug/cord in place. And then I would just leave it plugged in ALL THE TIME. The EVSE and its connector is sealed and weather-proof and engineered safe that way.

One issue here is if you want to carry that EVSE in your car when driving. In this case, I would just get another one and leave it in the trunk (it will never get used). Another issue is theft.... a thief could steal an EVSE left outside all the time. If it happens, just get another one for $150 and lock it somehow.

3. Rusty, if you are confused, keep in mind that the EVSE and the EV talk about what current/power to use, and decide to use the lower of their two capacities. The EV might take 50A 240V, but plug a 16 A 240 V EVSE into it, and they will agree on 16 A. No problem.
 
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RustyShackleford

Minister of Fire
Jan 6, 2009
1,133
NC
One issue here is if you want to carry that EVSE in your car when driving. In this case, I would just get another one and leave it in the trunk (it will never get used).

That's why I bought a "charger" (one of the $500 things that his hard-wired and has the safety-interlock thing, mentioned in post #37 item #2). Of course, it's not really a charger, that is in the vehicle; it's just a safe AC connection. I didn't want to leave the cord at home, in case I ever needed it on the road, and I didn't want to be plugging it in when it's wet.

. Rusty, if you are confused, keep in mind that the EVSE and the EV talk about what current/power to use, and decide to use the lower of their two capacities. The EV might take 50A 240V, but plug a 16 A 240 V EVSE into it, and they will agree on 16 A. No problem.
Yes, agree on 16A, but charge much slower.
 
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peakbagger

Minister of Fire
Jul 11, 2008
7,455
Northern NH
One of the few benefits of totaling my first Rav 4 was the charge cord was at home when it got hauled so I ended up with spare when I bought the second one;). I now have a 240 20 amp cord for the garage so I have two spares. I keep looking for charge stations when I travel just for the heck of it but unless I was there all day it does not make sense. I have in theory 600 miles range with my Prime (45 electric, 555 gas) so I just fill it up with gas until I get home. IMO supercharger type chargers are for full EVs. Battery life is also impacted with fast charges. In the long run its better to charge them slow.
 

woodgeek

Minister of Fire
Jan 27, 2008
4,680
SE PA
That's why I bought a "charger" (one of the $500 things that his hard-wired and has the safety-interlock thing, mentioned in post #37 item #2). Of course, it's not really a charger, that is in the vehicle; it's just a safe AC connection. I didn't want to leave the cord at home, in case I ever needed it on the road, and I didn't want to be plugging it in when it's wet.

Yes, agree on 16A, but charge much slower.

We agree. I just want to point out that ALL EVSE's, both hardwired and portable, have the exact same safety interlocks. I wouldn't want to be plugging and unplugging a portable EVSE all the time, esp in a wet location. If the OP was gonna sling his portable charger in and out of his frunk every time he or his wife wants to use it, and make and break 240V plug connections outdoors, nope, that is not a convenient or maximum safety plan.

But that said, a $150 portable EVSE, plugged in 'permanently' in a weather box (or with an indoor plug), is equivalently safe to the hardwired version that cost 3x more. And the portable on 240V and 3.8 kW, is a very cheap solution if you already have 12 gauge wiring which will be plenty of power for most users to be satisfied.

I have a $600 hardwired 6.5 kW EVSE I installed in 2014 btw. :)
 
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EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
I appreciate all the feedback.
 
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NoGoodAtScreenNames

Feeling the Heat
Sep 16, 2015
449
Massachusetts
IMO (and I am not an electrician) is that your installation is grandfathered but not in compliance with current code which was changed to include all outdoor plugs including 240volt. If it was hard wired into the panel with no plug and outlet that you are covered.

Good pick on the Prime ;) . If its a SE, the 20 Amp plug is fine but if you are buying the XE or XLE and want faster charging you can go with higher amperage circuit since you have the larger AC to DC converter. I am active on the Rav 4 Prime forum. Get ready for the inevitable cold weather fog horn mystery unless they have solved it and the "how do I quiet the choir of out of tune angels" question. Other than those annoyances, I am very impressed at the overall package. GIve me a PM if you want to talk factory tow hitches as I installed mine on my own.
Yeah - I’m going with the SE with weather package. The rest of the bells and whistles on the higher trim don’t seem worth it. I really wanted to pull the trigger on an EV - VW ID4 looked interesting - but couldn’t do it in the end when I modeled out my trips, particularly in winter. It was close but the Prime just made more sense in the end. I really think this will be my last car with a gas tank though.

The higher charge rate would be nice for when we are using public level 2 chargers. There’s a lot of Level 2 chargers around here north of Boston. But I wasn’t going to buy the higher trim which included an msrp markup not present on the SE and then the crazy premium package just to get the slightly faster charger. The lower charge rate actually works to my benefit. Since my solar isn’t truly net metered it’s more beneficial to have a lower load over a longer period of time than a faster charge that could force me to pull from the grid. Working from home a lot more now and having a charge time that fits into the daily peak from 9-2 works well. The Prius can fill up on the level 1 during that same time so up to 27 kwh per day from solar going into batteries instead of going back to the grid.

I’ve also been looking a lot at the RAV4 forum - it seems the biggest complaint right now is interior lighting (…yawn). I saw a Peakbagger over there and figured it was the hearth.com guy. I mean how many people are out there bagging up peak? Glad you picked a username you like. Mine tend to be cringey stupid and thereby different for each forum I subscribe to…all the good prime puns I could think of were already taken…
 

EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
Update….
The Tesla wall charger will be here next week. I have been hitting up the super charging station. Was fine the first two times then I thought I knew what I was doing (I am not the typical Tesla owner and playing the Tesla hits streaming radio station confirmed that ). On my third trip I got two bad chargers in a row and left, without a charge. Thinking it was some how my fault or an issue with Tesla accounts ect. I didn’t want to be that idiot backing into each and every stall and getting those stares. I drive home and plugged into to 120 V 12 A. 40 hours later I was fully charged. And the wall charger order was placed. Range is less than stellar in my city stop and go traffic and cold weather takes its toll. Needs new tires and an alignment. Doubt that will help range. This is the mixed car I have ever driven and makes me realize how clapped out my Odessey with 114k miles really is.

Reason I chose the Tesla charger is that it was priced competitively to most others and I can add a second and they “talk” to each to not overload the circuit they are both on. Others may do the same but didn’t have time to research any further. It’s been a super crazy two weeks.

Evan
 

EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
I have completed my first week of at home charging. Twice now I have gotten errors that prevented me from supercharging but each time an AC charger was able to charge the car.

Install was easy. Setup went fine. Decided to reduce the charging rate from 16A to 13A via in car settings. Breaker was warm and I’m sure fine. But I don’t need the faster charging as I am only charging 10-20 kWh a night.

Home charger has made life easier than hitting up free charging every 3 days. I probably will see 50% increases in my average electric usage. Far cheaper than gas.

Final thoughts to close this with.
Im not a huge Tesla fan. But 4 weeks with this car I am convinced that what ever you think of the brand and their products where they are miles ahead is in the self driving software. I have hardware from 2016 that’s working with the newest FSD beta. Coolness aside once they get a few more years down the line they will have in my opinion a safety factor that no one can touch. Sure it will barf and fail at times but so do humans, probably at a much much higher rate. Will the license this software?? Maybe. What’s it worth to have your car save you from an accident?

Evan.

C8170EB9-8EE2-4D73-8079-BE03135A53CA.jpeg
 

woodgeek

Minister of Fire
Jan 27, 2008
4,680
SE PA
How big is the breaker on the Tesla EVSE? I"m surprised you are charging at 13A (and I assume 240V).
 

EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
How big is the breaker on the Tesla EVSE? I"m surprised you are charging at 13A (and I assume 240V).
Tesla charger is configurable for breakers 60A down to 15A. You tell it it’s on a 20amp breaker, it sets max output to 16A. You can set charging rate via in in car interface as well. Charger only needs 2 plus ground (no neutral )

the circuit was the old well pump circuit. 20A single pole. I swapped in a tandem afci breaker on the left side of the panel to free up a spot for a 20A two pole. I confirmed the wire that I saw was #12 but I can’t say I could guarantee the entire run was so I dropped in the in car charging rate to 13 A at 240V. I could or maybe should have set the charger up as if it was on 15 A breaker but didn’t. I could always change That.
 
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begreen

Mooderator
Staff member
Nov 18, 2005
94,486
South Puget Sound, WA
I have a $600 hardwired 6.5 kW EVSE I installed in 2014 btw. :)
That's what we've been running on since 2013. Well, almost. Ours is 6kW. 99% of our charging is overnight or longer so no big deal. Eventually we may need to upgrade the circuit, but if one is not daily commuting then the need for a big charger is overrated.
 
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EbS-P

Minister of Fire
Jan 19, 2019
2,995
SE North Carolina
That's what we've been running on since 2013. Well, almost. Ours is 6kW. 99% of our charging is overnight or longer so no big deal. Eventually we may need to upgrade the circuit, but if one is not daily commuting then the need for a big charger is overrated.
My math says i can charge 30 kWh (assuming 85% charging efficiency) in 12 hours at 13A @240V. Given my mileage around town thats more than I need With a 100kwh battery charging to 70% each night.

I really want to look at charging efficiency and vampire drain, but Im afraid what I might find. Especially when it’s cold and I precondition the battery or preheat the car. At the end of the day I guess I don’t really care. I’ll keep The pre heats to a minimum and away from 3rd party apps so the car system’s will shut down More. I’m not Teslas demographic. But WOW! I might become a truck driver if the Tesla Semi drives as a good as mine.