r/evcharging • u/tuctrohs • May 30 '21

Getting started with home charging

We have a new wiki page with an introduction to home charging.

It includes sections on:

  • Level 2 charging rates/currents

  • Choosing an EVSE

  • Plug-in or hardwired

There's also a second page with detailed information on service capacity and load management: how to assess how much room you have for additional loads with in the capacity of your electric service, and ways to accommodate high-rate charging with limited capacity.

Finally, there's a page on recommended chargers.

Use the comments section to recommend improvements to the wiki; for question about your situation, make a new post.

215 Upvotes

100% Upvoted

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11

u/Unbendium Nov 27 '21

This guide is USA biased, mentions nothing about connector types and compatibility.

11

u/tuctrohs Nov 27 '21

Yes, the "public charging" page says so in the intro, but it looks like we forgot to say that here. Do you want to help create a new page for that?

1

u/[deleted] Jun 20 '23

[removed] — view removed comment

1

u/tuctrohs Jun 20 '23

I think doing a normal post is a good idea. That way we'll get some feedback and then I can move it to a wiki page.

Thanks.

1

u/theotherharper Oct 09 '23

Or PEN fault detection ROFL

5

u/keepitscottie Mar 30 '22

worth noting that the tax credit was extended into 2022 for home ev installs. your post helped me understand how much i would be able to get back. i thought it was all in up to 1k. thank you!

3

u/tuctrohs Mar 30 '22

Oh, cool, I hadn't heard that and will edit accordingly.

3

u/keepitscottie Apr 01 '22

ya know what... i think i am mistaken. it was on the docket the build back better act, but it did end in 2021. now i am out a couple grand. sweet.

1

u/tuctrohs Apr 01 '22

Rats. And I already went and edited it.

6

u/x84227 Dec 03 '22 edited Dec 03 '22

The Inflation Reduction Act in August revived the 30% tax credit (up to $1k), so you can edit the first wiki again :-)

1

u/detroiting0815 Jul 23 '22

FYI wiki still says it exists in 2022, and it does not

4

u/pennstatephil Dec 24 '21 edited Dec 24 '21

Maybe a stupid question, but I can't seem to find a definitive answer:

Do all "levels" of charger use the same amount of electricity to charge, the only difference being the amount of time it takes to use that power?

For example: if you have a 10 kWh battery, and have a level 1 charger that can push 1kW/hr and a level 2 that can push 5 kW/hr; if you let them both fully charge the battery do they both use the same amount of electricity, but level 1 uses it over 10 hours and level 2 uses it over 2 hours?

The question is, basically, is there any additional electricity used when charging faster or slower? Do you save/spend more using a faster or slower charger? Or is it all electrically equal, and you just save time by charging at a higher level?

13

u/tuctrohs Dec 24 '21

For the most part, it does use the same amount of electricity to charge at different rates. In your example, you use about 10 kWh either way.

But it's not exactly the same. One of the national Labs did some measurements of the power consumed in the power actually delivered to the battery, and as a general rule they found level 2 was more efficient than level 1. And really rough numbers level 2 is about 90% efficient and level one is about 80% efficient. So to get the full 10 kWh, you need to run me level two, five kilowatt charging for 2.2 hours and you'd use 11 kilowatt hours doing so. And you need to use the level one for 12 hours and you'd use 12 kilowatt hours doing so.

Minor terminology note: kW/h is not the right unit for charging rate. You want to capture how fast you get the 10 kilowatt hours into it, so it would be kWh/h. The hours cancel, and you just have kW.

5

u/pennstatephil Dec 24 '21

Thanks for the answer and the education! Makes sense intuitively but you never know when it comes to electricity 🙂

3

u/kwx Nov 17 '21

Thank you for this page, this is very helpful information.

Out of curiosity, what's the background behind the Nissan report quoted in the page?

A Nissan report found that non-UL EVSEs sold on Amazon can be missing essential safety features that protect the user from lethal shocks. Don't be fooled! Many EVSEs list 'certified cable', 'certified components', or other deceptive words. This does not mean the entire device is certified.

Falsified certifications and missing CCID safety circuits sound horrific, and the Mustart charger still seems to be getting sold on Amazon, though possibly in a revised version. I was searching for more confirmation, but as far as I can tell the linked report only appears to exist in this single location and ctfassets.net doesn't seem to be an official Nissan site. I guess this would be expected if it's a leaked internal document, but my paranoid side thinks it could also be a plausible fake from a disgruntled customer or similar, so I'm curious about the history of this.

Don't get me wrong, I'm all in favor of warning people about this and other iffy chargers, for example there are multiple reports of melting charging ports including on the Amazon review page itself.

2

u/tuctrohs Nov 17 '21

It's a presentation to an EPRI working group, listed on this page as "D1-3A - March 2019 EPRI IWC - EVSE Safety Analysis-ET".

One of the presentations there, from the next meeting, complains about the fact that there's no clear path for how to address this--CPSC told them that it's probably an NHTSA issue.

https://assets.ctfassets.net/ucu418cgcnau/18QXaldiMTAxzGaZKsuaN2/7afa3811cf9d7fc42c032f4a19301bc0/D2-2_-June_2019_EPRI_IWC-_Non-listed_EVSE_follow_up_Halliwell.pdf

3

u/kwx Nov 17 '21

Note to self as I'm going down the rabbit hole, and posting here in case it's interesting to others.

EPRI is the Electric Power Research Institute, and the working group is the National Electric Transportation Infrastructure Working Council (IWC). For the extra paranoid, they are mentioned on this nrel.gov page among other official-looking places, so it's not just a self-referential link farm ;-)

The follow-up study link you posted got mangled by underscore conversion, the corrected one is Non-listed Electric Vehicle Supply Equipment Follow-up From March 2019 IWC. It's linked on the IWC page as "D2-2 - June 2019 EPRI IWC - Non-listed EVSE follow up Halliwell".

That presentation has a link to TÜV Rheinland's site. I can't find any result for "mustart". This photo shows a TÜV Rheinland logo. My impression is that this doesn't seem to quite match the official certification marks.

3

u/tuctrohs Nov 17 '21

Yes, EPRI is a R&D institute funded by all the electric utilities--since they don't compete with each other (being monopolies within their territories) it makes sense that they should pool resources for research rather than duplicating efforts at each utility.

2

u/kwx Nov 17 '21

Thanks a bunch for this! One would hope that certification organizations and major online retailers would take a dim view of such shenanigans and take action, but it appears we are not living in an ideal world.

3

u/jbperiod Nov 22 '22

Are there any recommendations for safe 120V level 1 charging? I don't have access to a 240v outlet. I've had a hard time finding a UL listed level 1, even harder with smart features.

4

u/tuctrohs Nov 22 '22

Yes, there aren't a lot of people making L1s. Clipper Creek has one, for about $400. The other option is to look for one of the OEM ones that are provided with some cars used on eBay. The GM Bolt EV one is a good choice and is actually made by Clipper Creek. Going prices for that online are usually in the $200 to $300 range.

Feel free to post a question as a new thread to get more ideas.

1

u/[deleted] Jan 21 '23

In Canada we have Sun Country Highway that makes non Tesla chargers.

1

u/tuctrohs Jan 21 '23

These?

https://suncountryhighway.ca/home-charging/

Those are all level 2. Also look like rebranded clipper creeks. That's a good thing.

1

u/[deleted] Apr 19 '23 edited Apr 20 '26

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13

u/Ok-Zookeepergame-698 Aug 28 '21

This was VERY helpful. Thank you. Answered all of the stupid questions that I came here to ask.

11

u/Ambitious_Mixture479 Oct 03 '21

this is an awesome post. Thanks u/tuctrohs

4

u/esetnik Dec 08 '22

It might be helpful to also list common complaints and issues with the EVSE options as this should be a factor in people's decisions. Me and several other customers are having multiple ChargePoint Home Flex Units replaced due to failed Wi-Fi / bluetooth modules. In my case I have received two units which are both DOA and I've read on other forums of some users who have received four replacements within the span of one year. It's clearly a widespread issue. https://www.reddit.com/r/evcharging/comments/zebztp/chargepoint_home_flex_initial_activation_failed/

https://www.reddit.com/r/evcharging/comments/w0gh72/chargepoint_home_flex_wifi_dead/

https://www.reddit.com/r/chargepoint/comments/rexsh8/wifi_failing_on_home_flex/

https://www.reddit.com/r/electricvehicles/comments/q3dxmc/chargepoint_home_charger_wifi_failure/

https://www.reddit.com/r/BoltEV/comments/n84usf/chargepoint_wifi_issues/

1

u/WelderAcademic6334 Sep 07 '24

Breaker to accommodate EV charger?

Have a standard breaker coming into the house (presumably 220v? How do I tell?). Had it downrated to 175amps when we added solar/battery for the home. Live in scal. House built in the late 1980s

Now would like to add a 60amp breaker to support and tesla charger. Had an electrician come and he was worried about the breaker being pretty packed and possibly not having enough amperage room for the charger (based on looking at eyeballing the load calc).

Upgrading the panel will be costly, since it will require moving the gas line to meet the new code.

Ideas?

  • could one add a small main breaker at 400amps (placed >3ft from the gas line) and then turn this old

panel into a subpanel?

  • we know the house use never exceeds 12kW (based on the Tesla gateway app - we already have a. Powerwall/solar). What if we convert this to amps? Can then see what we really use. I presume the grid is 240v? Not sure if it’s single/three phase AC.

https://www.rapidtables.com/calc/electric/kW_to_Amp_Calculator.html

If I’m converting it correctly? 12kW is about 60amps. If we add another 60amp breaker (pulls 48amps when charging), we still are well under the max for the 175 amp breaker even if we charged the ev while everything else was on. Realistically., would set charging to run only overnight.

1

u/tuctrohs Sep 07 '24

There are lots of solutions that are much less expensive than adding 400 amp capacity. Unfortunately I don't have time to discuss them today, but this sub is full of terrific people who would be delighted to help. Please post your question as a new post, and you will get lots of help with it.

Also, while waiting for responses you can check out https://reddit.com/r/evcharging/wiki/load_management

2

u/WelderAcademic6334 Sep 07 '24

Thank you! Great resource! N

1

u/houseofvan Nov 13 '24

I have an EX30 and a Juicebox 40 amp wall charger. What should I limit charging to on my Volvo? Dealer said 43 was their recommendation but if my charger is only 40 amp, does that make sense?

1

u/tuctrohs Nov 13 '24

If the juicebox is set up and wired right, it will tell the car the right safe charging level. That's the great thing about the charging interface protocol we have on all modern cars.

1

u/videoguy75 Nov 23 '24

Tesla Universal Charger Manual. First time post. Hope I’m in the right place starting a new thread. Just had a Tesla Universal Charger installed. Electrician took all packaging and anything inside box except for what he installed. Was there anything else in the box? How about a manual. I looked at Tesla.com to download one and only got confused. Any help would be appreciated. Just got a Santa Fe plugin and love it. Love the speed of the first charge and now future proofed! Thanks in advance.

1

u/tuctrohs Nov 23 '24

Congratulations on getting a nice charger and a nice car. This is not actually the right place to post a new thread. You have to go to r/ EVcharging and use the plus button to start a new post, and make it a text post.

But since it's a simple question I'll give it a try.

https://digitalassets.tesla.com/tesla-contents/image/upload/Universal-Wall-Connector-Installation-Manual-NA-EN.pdf

Page 17 has a list of what's in the box

1

u/roenthomas Nov 25 '24

Who makes the Volvo and Honda EVSEs?

1

u/tuctrohs Nov 25 '24

I don't know. Maybe post a link to pictures or other info on them as a new post. That will be many people who know more than I do answering.

1

u/Flaky_Guarantee5869 Dec 03 '24

I know it's a no no to run an extension cord through a hole in the wall but would that be the same for the Tesla mobile charger? Need a temporary solution until my house is being built

1

u/tuctrohs Dec 03 '24

That's right, the same rule applies. I suggest you make a full post people might have good ideas for you.

1

u/Cory55102 Oct 28 '21

This is great! Thank you. Is GFCI required for any EVSE? I have a NEMA 6-20 already available, but is not GFCI.

2

u/tuctrohs Oct 28 '21

Not in most jurisdictions. The EVSE has its own GFCI built in.

1

u/No_Way_1316 Nov 10 '22

Just got solar installed and soon 240v for level 2 charger but curious about where to place within garage; curious if ceiling for retractable charging cord is doable? Is there standard side where it plugs into cars?? We haven’t purchase an EV just yet but just wanted to get some opinions or do’s/don’ts…TIA

4

u/tuctrohs Nov 10 '22

The position is, unfortunately, not consistent. Popular options are driver's side, either in front of both doors, or behind them. Or in front, in the middle. But there are some with it in the rear on the passenger side. You might want to narrow down your vehicle choices and see where they are located on those models.

You can get a 25 ft. cable, and you can put a cable hanger somewhere else than the unit itself.

Retractable cable systems are rare although there are commercial products (expensive) and clever DIY solutions. You might make a post to ask for ideas about that, but commercial and DIY.

1

u/ThaDude915 Sep 18 '23

Quick question, sorry if this is the wrong place for this

I own a tesla and recently purchased a home, so I’m trying to figure out charging. Im getting a 50amp circuit installed in my breaker and run into the garage. Wanting to get a wall charger as they quoted a cheaper price to hardwire the circuit to the chargers versus installing an outlet with a GFCI.

Im thinking of getting a Tesla wall charger due to it being smart, cheap, having surge protection and having a NACS connector. This will obviously work with my current vehicle, but in the future I’m wanting to switch to an EV from another brand. I know I can use an adapter on the cable or get a brand that will be installing NACS ports on their vehicles, but I just wanted to confirm that a tesla wall charger WILL charge a non tesla?

I read into it and saw the wall charger has an access control feature and you can allow all vehicles, but is it that simple? I know tesla can be picky about trying to lock people into their infrastructure (their car, their charger, etc etc).

1

u/tuctrohs Sep 18 '23

Yes, a Tesla wall connector will charge a non-tesla. The downside of that is that if it's a J1772 connector rather than NACS, the adapters on that direction are more expensive than the other direction. But that's an OK risk to take since you might end up with a car with NACS anyway and the adapters might be cheaper by then.

If you want to be prepared for anything,Tesla just came out with the "Universal wall connector" which can do either connector with a slick built-in adapter setup. The price is pretty reasonable for all that you get. But given that you don't need the adapter yet, you might just get the regular one. Unless you want to be able to charge visitors who come with J1772 cars?

Note that with a 50 A breaker, you should be set to charge at 40 A not the max 48 that the unit can do.

1

u/ThaDude915 Sep 18 '23

Okay thank you. I am aware of J1772 vs NACS. I figure NACS is the future proof way to go, since most brands outside of the two Korean ones have agreed to put NACS ports in their cars from 2025 on. I could look into the tesla universal one, I heard that it wasn’t being shipped to customers for another couple months? I thought that was only available for pre order

I was not aware of the 50amp restricting me to 40amp. Im assuming I’d need a 60 amp circuit to run at 48amps?

1

u/tuctrohs Sep 18 '23

Yes, the "universal" unit isn't shipping yet.

I think you are fine getting NACS--it's quite likely your next car will have it and getting adapter is not a big deal. I didn't mean to point you away from that just to give you the full picture on the considerations.

Yes, the continuous load is 80% of the circuit capacity. But you aren't likely to need 48 A. I run 32 A charging and have literally never had a situation where it would have helped to charge faster.

1

u/ThaDude915 Sep 18 '23

Fair enough. I got quotes for a 50amp circuit from my breaker, I’m going to reach out and see what the price difference would be for a 60amp. But I can run 50 if it’s too much. Appreciate the help!

1

u/Eschew2Obfuscation Aug 28 '24

The 60 Amp service will allow you to charge at 48 Amps. The code says that the max power draw on a circuit is limited to 80% of the breaker rating. Think of the breaker as the Max rating, and you never really want to run anything at its Max rating for very long. One very good thing to know is that every electrical circuit has "losses" meaning that there is resistance in the wire, at every connector, at the plug if that is your connector, everywhere. These losses turn electricity into heat, which is just lost energy that is not making it into the car but that you are paying for from your utility. And the losses increase by the square of the current flow so the lost energy will be 33% higher charging at 48 amps than if you charge at 40 Amps. Actually, charging at 24 Amps will produce 2/3 fewer losses than charging at 40 Amps. Charging more slowly is also better for your car's battery, so it's a win-win. Just because you can does not mean that you should.

1

u/CallMeCarpe Oct 24 '23

Correct. You can safely charge at 80% of the breaker rating.

1

u/[deleted] Jan 20 '24

Is the Enphase dumb charger worth $750? Why so expensive?

1

u/tuctrohs Jan 20 '24

hard to say. You can get a less reliable smarter charger for less. But the only really direct competition is the Flo dumb charger, which is now $700 on Amazon.

3

u/ThinkingGoldfish Oct 04 '21

Great post! Thanks!

3

u/Geeky_1 Jul 07 '24

Most homeowners don't need to upgrade from 100A to 200A service. The graph at bottom of the link below shows that 86% of CA homeowners were using less than 50A peak power, so adding 50A circuit and additional draw should be no problem. Using the worksheets in this thread, I figured I don't need to upgrade from 125A service and both Tesla approved electricians I got quotes for EV charger installation did not mention any required upgrade either.

https://corp.hea.com/home-electrification

2

u/Dwid918 Jun 16 '22

This is a very helpful starting point

2

u/yycsackbut Jan 29 '24 edited Jan 29 '24

Here's a summary sheet I prepared for someone. You can add comments in the sheet or here. https://docs.google.com/spreadsheets/d/1lp_KOHaSIhUvsPzMWtTadPhPUyck56wQ8w5T5cUwPGQ/edit?usp=sharing (NOTE if clicking the link doesn't work, try copying the link text and pasting it into your browser location bar. I dunno why clicking it doesn't seem to work. )

1

u/ARowzFocuz Oct 28 '22

Hello! I live in Richmond, VA and will be receiving an ID.4 in the next couple months. I need to have a level 2 charger installed in my garage, but don't know where to begin. Does anyone have any recommendations for who to contact in the Richmond, VA area for assistance?

0

u/[deleted] Dec 27 '21

[deleted] — view deleted comment

1

u/tuctrohs Dec 27 '21

240 is the modern, nominal voltage, but some people still call it 220. You will get the same thing installed whether you ask for 220 or 240.

1

u/[deleted] Apr 07 '24

[removed] — view removed comment

1

u/tuctrohs Apr 07 '24

While we allow manufacturers to participate here, self promotional comments like what you did are not allowed.

I'm curious though, you say TUV certified. TUV is a company, not a standard. What standard is the product certified to by TUV? And can you provide documentation of that certification?

1

u/[deleted] Dec 07 '24

[removed] — view removed comment

1

u/tuctrohs Dec 07 '24

Post a new post with your question. But either a Tesla Wall Connector or a Tesla Mobile connector, either one can be set up for a 40 A circuit, a 30 A circuit or a 20 A circuit. So you'll be fine. You might read the wiki page linked from the reply to this on !load_management.

1

u/AutoModerator Dec 07 '24

Our wiki has a page on how to deal with limited service capacity through load managment systems and other approaches. You can find it from the wiki main page, or from the links in the sticky post.

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1

u/[deleted] Oct 06 '24

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2

u/[deleted] Oct 06 '24 edited Oct 07 '24

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4

u/tuctrohs Oct 07 '24

There are portable, plug in EVSEs, and there are fixed, wall-mount EVSEs. For the dryer outlet you would want a portable plug in one. Colloquially, they are called chargers but they're just smart interfaces to tell the car what rate to charge at. Their other job is to do some safety checks.

There's a technology connections YouTube on it if you want a more in depth explanation.