Cheap Charging: Level II Doesn't Have to Cost $2,000

By · November 14, 2011

Leviton Charger

The range of Leviton Evr-Green chargers: 240 volts with portability and a dryer plug for around $1,000. (Leviton photo)

Let’s face it, electric vehicle charging is overpriced for what you get. At an average of $2,000 for an installed 240-volt Level II garage charger, people are getting hosed. And that’s why the search is on for a cheaper alternative.

Going the budget route usually means 120-volt house current, and a long overnight of charging (20 hours in the Nissan LEAF, for instance), but not always. Manufacturers are cutting prices and offering some pretty cool options. Siemens, for instance, just introduced a 240-volt wall charger, the VersiCharge, that’s designed to sell for less than $1,000. Installation may not cost anything at all because the Siemens unit comes set to plug into a dedicated 30-amp, 240-volt outlet. Even if you don't have a 240-volt dryer-type outlet, one can be installed for around $200 (better to have an electrician do it).

Install it Yourself

The price is significant, because chargers that plug in are typically more expensive than hard-wired units. The VersiCharge is available in both 30- and 70-amp models, and both are adjustable—the 30-amp model from 1.8 to 7.2 kilowatts, and the 70-amp unit up to 16.8 kilowatts. The chargers are set up to communicate wirelessly with Zigbee-enabled devices, including smart meters, and both can be upgraded to access cellular networks or Wi-Fi.

Two cool features, especially considering the price: there’s a “dashboard” that gives you the current price of electricity, and a smart socket that enables communication with your utility so charging can be controlled remotely during peak demand times.

Leviton makes a similar Evr-Green Level II charger with “do it yourself” plug-and-play installation for $1,049. It’s not strictly portable, but it can be easily detached and moved.

The 120-Volt Option

Most EVs come with a 120-volt charging cable that allows a quick plug-in no matter where you are. Phil Sadow, a California-based electrical engineer, has applied an “upgrade” (its word) to Nissan’s cable that allows it to also charge at 240 volts. Send Sadow your cable, and for $239 he sends it back ready to plug into a 240-volt outlet (while retaining 120 charging). If you don’t have your own cable to supply, the cost is actually as high as the Leviton or Siemens units, $979.

The cables have proven popular among Leaf owners, but are they a good bet? Automakers and charging companies universally discourage EV owners from using “hacked” cables. “How safe do you think it is?” asks Pat Romano, president and CEO of charging company Coulomb Technologies. “The Nissan cable is rated for 120 volts. If you make aftermarket modifications there’s a risk of fire.” It's not surprising that Coulomb would cast doubt on a product that's considered just as capable of getting the job done, at a significantly lower price than what it's offering.

Playing With Fire?

There's the same resistance to portable 240-volt charging from carmakers. Rich Steinberg, BMW’s manager of EV operations and strategy, likened buying a modified charging cable to “playing with fire.” Steinberg's position—some would call it alarmist—may be more technocratic in nature. He points to the voluntary National Electric Code (NEC), which says in article 625 that 120-volt, 15- or 20-amp charging equipment “shall be permitted to be cord and plug connected,” but all other EVSEs “shall be permanently connected and fastened in place.” That means wall mounted.

That regulation explains why we don’t have racks full of commercial 240-volt charging cords, but at 120 volts they’re imminently marketable. And a company called PlugSmart, partnered with TE Connectivity, is set to introduce a relatively low-priced “smart” 120-volt charging cable. According to Dave Zehala, PlugSmart executive vice president of business development, the unit could be sold at big-box stores in the $300 to $400 range.

Aaron Martlage, vice president of global strategy at PlugSmart, said that NEC rules don’t have the force of law, but are widely respected. He said that PlugSmart won’t be getting into the 240-volt business, but its 120-volt cord is aimed at two markets: Consumers who might want a means of plugging in at home or on the road, and workplace use, with users connecting to separately metered house-current outlets. Although 120-charging may not be effective for plug-in electric cars with large battery packs, Martlage said it is ideally suited to the plug-in hybrids (with smaller packs) that he expects to be dominant in the marketplace.

Martlage said the device is set up to make it easy for employers to bill users for the electricity they consume at such outlets. “It’s not just a glorified extension cord—we think there’s a market for a superior Level I charger,” he said. “The unit authenticates with the socket and identifies the user, avoiding the workplace problem that free electricity could be seen as ‘ordinary income’ to the employee. The unit is also lockable, to prevent anyone unauthorized from disconnecting it during a charge.” A pilot program begins in December, and the unit, with no final price yet, will be widely available in early 2012.

Make it Portable

Leviton, in its Evr-Green line, makes a fully portable 120-volt charger for $950. It features, among other things, a carrying handle and automatic restart if the charge is interrupted.

According to John Hewitt, a TE Connectivity vice president, “Ubiquitous, cost-effective connectivity is essential in this market.” And that’s why Nissan’s latest move, though it has nothing to do with home charging, is significant. The company announced last week a 480-volt DC fast charger priced at under $10,000. That’s huge, considering some fast chargers are priced as high as $50,000.

DC fast charging takes only about half hour for most battery EVs, but the limitations of home electric service means you’re going to be encountering these units mostly in restaurant parking lots (Cracker Barrel is installing a network of them in Tennessee) and gas stations (Nissan is negotiating with several large chains).

Still, a cheaper DC fast charger will probably mean lower-cost public fill-ups for EV owners, and it’s a very welcome development. EV charging is still a work in progress, and further bargains are likely to start cropping up.


· · 6 years ago

You're completely missing Tesla's Universal Mobile Connector (, something that the companies who don't want EVs have completely neglected.
I suspect that more long-distance EV trips have been driven using these than any other kind of connector since they easily allow use of RV parks or Dryer outlets anywhere.
Sure, NEC 625 doesn't like these and, conveniently, electricians and bureaucrats tend to love the job and gasoline protecting nature of NEC 625 but that doesn't make it right.
This article also acts as if there is something strange about an EVSE for under $1,000 when the first AeroVironment ones came out at less than $800 from the start.
Most of the cost of installation by national footprint installers such as Blink and AeroVironment involves dealing with the various bureaucratic permitting and approval roadblocks that vary from city to city and county to county. Local electricians can either ignore these or may be familiar with ways to streamline these so they can likely reduce their costs.
As EV installations become more common, hopefully, these costs will decrease, on the other hand, they could also increase if bureaucrats capitalize on demand for EVs as a means of siphoning yet more money from the public.
It will be interesting to watch. I often look at the "Activity" tab on or to watch the new chargers that have been installed. They are happening slowly but progress is definitely happening.

· · 6 years ago

We purchased the Scneider wall unit for $800 w/ free shipping from Home Depot and installed it ourselves with about $90 worth of misc electrical parts.

· · 6 years ago

I understand Richard Steinberg's apprehension to support buying modified charging cables. Once bitten, twice shy they say, let me explain.

When the MINI-E program was launched there was a huge problem with getting the units approved by local inspectors. The problem was the EVSE's came seperate from the cables with the connectors attached. The electrician installing the units attached the cable on site. This seems harmless, right? The electricians are licensed and all they needed to do was attach four wires inside the unit. The inspectors disagreed. They contended that since the units had UL approval as a "complete unit" that adding the cable outside of the factory was now a modification to the unit and they wouldn't approve it. It was a disaster and Rich was in charge of dealing with each inspector that failed the units. I got my MINI-E in June 2009 and my wall charger wasn't approved for use until December! That dosen't mean I wasn't using it, it just wasn't approved for use. The good thing for me was that BMW couldn't charge us the monthly lease payment until we had a working, approved EVSE installed in our homes, so I got the first six months use of the car FREE. I wasn't alone, there were probably about 100 of us that failed inspection and the local inspectors were each giving Rich different information and requirements. BMW had to actually remove my EVSE and install a brand new one that had the cable installed in the factory before my inspector would approve it. They then took my original EVSE and installed it in someone's house, because there was nothing wrong with it. Rich was beat to death dealing with the inspectors and they were telling him how the units all had to be hardwired, and completely assembled at the factory for UL listing, I even had my inspector ask if I knew if it was explosion proof, since it was in the garage where gasoline fumes are normally expected.

This was in 2009 when (outside of California) hardly and electrical inspectors had even seen an EVSE let alone had to approve one. Hopefully that is changing now. However Rich isn't the only one that points to the National Electric Code Article 625 that states all electric vehicle EVSE's other than 110v shall be hard wired. Leviton has stated that they interpret the code differently and that the plug-in level 2 chargers are allowed. Other EVSE manufacturers aren't so sure about that still and have kept to the hard wired approach. Personally I like the portability of the plug in Leviton unit. All you have to install is a 220v outlet at, lets say your parents house, and you can bring the EVSE along when needed. You could also make use of the many campsites that have 220v electric available for the campers that need it.

· Anonymous (not verified) · 6 years ago

I believe that the issue of cheap charging is not really about charging it cheaply, i.e. cheap equipments and installation. Those can be done, cheap, and QUICK.

The problem is with following all the local ordinances and regulations, as well as insurance requirement. W/o approval from utility/city/hoa/etc. - the EVSE upgrade is an example, using equipment that is not approved for such modification (not saying that it's unsafe, however), if a fire broke out, or any damage that affects other, the liability is huge, and insurance company will most likely reject claims in such manner.

Liability, I believe, is the reason that incurs a significant cost to the charging equipments and installation for home use.

· · 6 years ago

People who convert their ICE cars into EVs have been using 220V dryer plugs for decades now. If a dryer draws 30A and an EV charges at 20A, there is quite a margin of safety there. There are certainly better physical plugs to insert and remove on a daily basis (mechanically speaking), but this problem is not really as mysterious as many makes it out to be. The critical thing is that all the components, including the wiring, is set up for an amperage (in continuous use) in excess of the charging draw. Really electricians should be able to figure this out using UL approved and amerage and voltage rated components.

What is really needed is an education program directed at local inspectors and other local officials.

The same sort of thing happened with hydrogen fueling stations for fuel cell cars. At first the local fire inspectors froze up and did not allow anything to happen. Then various companies and other entities pulled together a set of documentation showing what type of equipment was safe with hydrogen and, armed with this documentation, a few local fire inspectors were found who could act as spokespeople to other local fire inspectors across the country. Pretty soon it did not take so long to get approvel for a hydrogen fuel station or similiar apparatus.

· Kei Jidosha (not verified) · 6 years ago

Plugging vehicles into 240 volt, 50 amp outlets is not rocket science. RV owners have been using non-GFI outlets for decades. Failure to supply a simple engineered portable power solution at a reasonable cost is what invites disaster. It does not have to be this expensive or complicated. NEC and the other stakeholders need to get reasonable.

· · 6 years ago

I suspect in a year or so we'll see $200 240V EVSEs from China being regularly sold on Ebay. These EVSEs will be no feature devices without UL. But people will buy them.

· · 6 years ago

For what it's worth, my Clipper Creek units (I have four of them) are exceptionally well built and durable. They are made of airline grade plastic and are so strong I'm sure they can withstand a blow of a heavy sledge hammer. They aren't the lease expensive EVSE's out there but they are extremely well built.
If you plan on driving electric cars from now on, I urge you to buy a high quality one. I have no doubt the Clipper Creek units will last me decades. I'm not sure I want a piece of cheaply made Chinese sh** in my garage when I'll be running high amperage through it for thousands of accumulated hours, many of which while I'm sleeping!

· LSapoVerde (not verified) · 6 years ago

There are some good reasons for the NEC rules (safety, standardization, etc), but at times they can really stifle innovation and creativity. I agree that it is really important to protect the average consumer from himself and nature, but at the same time, people have been using electrons to do things for a long time. This isn't that big a deal.. I wrote a while back about using two 120 circuits to charge at near Level 2. While I don't encourage getting overly creative if you aren't knowledgeable, I don't think we have to buy only what we are spoon-fed.

Like Tom and others, I'm eager to see prices on high quality EVSE's drop. I think they'll get there because people like Phil Sadow keep pushing the envelope.

· · 6 years ago

Unfortunately, the people I know who have been the most vocal proponents of evseupgrade's hacks are often those who know the least about what they are getting. They only seem to comprehend one thing - the price.
SPX has a J-1772 L-2 connector that can plug into a 240 volt outlet isn't much more expensive than a hacked Nissan L-1 cord if you count the cost of the L-1 cord. I, personally, prefer to keep the L-1 cord as a reliable backup, therefore, I'd only consider buying the evseupgrade hack with a new Nissan L-1 cord. The cost difference is minimal and the SPX L-2 connector will enable 30 amp charging so it is much more future-proof.
I'm not buying either since I'm waiting for a more reasonable form-factor than the huge, unnecessary box that is on the Nissan unit. I guess I'm just spoiled by Tesla's useful charging offerings (

· · 6 years ago

If you go to the Tesla link that ex-EV1 driver just posted, notice the dryer plug option for the Tesla Roadster. The electronics should be in the car with an absolute minimum on the wall. I am not necessarily advocating a dryer plug per se, but that there is really less going on in this issue then it appears. An EV is not any different than any other load with the same continuous current and voltage. The electrons don't know if they are going into an EV, a dryer or an RV.

· · 6 years ago

If you follow ex-EV1's link to the Tesla site and click on "High Power Wall Charger", that is the Clipper Creek EVSE I was referring to above.

Here's a photo of the two I have in my garage. Notice a Roadster and my MINI-E charging at the same time :)

· · 6 years ago

@ Tom Moloughney - That's what I like to see: any EV should be able to plug into any outlet. Because EVs and plug-in hybrids have enough of a struggle to take over the car market without fighting between the car brands on plug standards.

· Norbert (not verified) · 6 years ago

@alt-e : Not possible to get DC fast charge through a standard J1772 plug, though.

· · 6 years ago

No, but the fast DC charge is not likely to be in the home but out in the world some place where people use it occasionally on trips and therefore it can cost more.

· · 6 years ago

Leviton evr green chargers are best as they are flexible and weatherproof.

· Lad (not verified) · 6 years ago

I have the Upgraded Nissan Brick mounted on my garage wall and pluged into a 240 outlet that I installed...working great for at least 6 months. And when I plan a long trip I carry it along in case I need a charge from a trailer park or other 120 or 240 source.

EVs have a requirement ICE machines don't. It's called charge planning; however, there may be a time when the Level 2 EVSE, I plan to use isn't working, etc. So then I impliment plan B...the portable 120/240 Nissan EVSE with an adapter.

BTW, Home Depot has a level 2 DIY EVSE now priced at $749. In March when I took delivery of my Leaf EVSEs were $2000. I see a trend here.

· · 6 years ago

Are these DIY Level 2 chargers capable of 6.6kW or just 3.3kW? Is this just a matter of the circuit it is connected to, or do you specifically have to use a Level 2 charger that can handle 40A?


· Eric (not verified) · 6 years ago

Here is a link to the charger mentioned elsewhere in the comments from Home Depot. It is 30A.

· Bill (not verified) · 6 years ago

The EV Project ( has a grant from the feds to install Level 2 chargers for free. It covers both residential and commercial. I signed up and will see how free it really is tomorrow. In Los Angeles, DWP offers $2,000 in rebates for installation and purchase.
Get a good charger, but get it free.

· · 6 years ago

You'll get a free charger but it certainly may not be a good one. The Blink has a lot of room for improvement.

· · 6 years ago

The same sort of thing happened with hydrogen fueling stations for fuel cell cars. At first the local fire inspectors froze up and did not allow anything to happen.

· Joe (not verified) · 5 years ago

Just made a "Voltech" Volt Fast Charger portable with a "Quick 220" system.
Works beautifully! I can now take my fast charger and plug it into any regular outlets.
Just need to find two plugs on different circuits, presto!
A cheap fast charging system that can go anywhere.
With parts and including shipping $825.00 and all it's parts made in the USA.
Why can't anyone else think of this...?!

· Bill Howland, (not verified) · 5 years ago

I'd vote for a hot tub ground fault interrupter and a standard twist lock, but since the NEC is based on a certain amount of collusion, there was too much temptation for money to be made.

That J1772 is somewhat of a joke, There are 4 subtending UL standards also, and products that are J1772 compatible don't work with each other. But spending all that money for a glorified light switch is depressing. And the light switch is not necessarily compatible with all vehicles. Anyone know whether the 30% federal tax credit is still in effect?

That inspector comment was great.. He doesn't know about the 18" off the floor thing. Also ask him if every light switch he's seen in a residential garage is explosion proof.

· Charlie Barrett (not verified) · 5 years ago

I would love to see a schematic of a Level 2 charger.

I have a feeling that it consists of about $100 worth of electronic components. I would hope my MIEV has all the charge controller circuitry built into the car, because every electric car has different specs for charge rate, max charge kwh, and probably even different battery operating voltage. I think my Mitsubishi MIEV's internal battery voltage is 330VDC for example.

Either the car or the charger must boost the 120vac or 240vac to over 330VDC in order to charge the batteries as configured - but the car may have relays or power MOSFETS (transistors) to reconfigure the 3v Li-Ion cell hookup to put fewer of them in series and more in parallel to allow it to charge on less voltage - i wish I could get ahold of my car's schematics and technical manuals so that big mystery is solved.

There is absolutely no reason an electric vehicle couldn't be designed to accept a 120 volt extension cord, a 220v dryer cord, or a 3-phase AC connection with ZERO electronics in the cord and tie-in box, except maybe surge suppressors and GFCI circuitry to disconnect the power if it senses any electrical leakage to ground. Again, that should cost around $100, not $900!!!

· · 5 years ago

@Charlie Barrett,
You're right in your guess that there are only about $100 worth of components in a J1772 Level 2 charger. The component prices probably vary from around $50 for a 120v/12 amp one to maybe $200 for a 240v/30 amp one to perhaps more for the high power 240v/70 amp ones. Networked chargers and ones with fancy display monitors probably cost a bit more but no one really needs all that junk. Technically, the "charger" is called an Electric Vehicle Support Equipment (EVSE).
What it really is is a glorified extension cord with a relay contactor to automatically shut it on and off as well as some simple communications circuitry that communicates with the car to determine if it is safely connected before closing the relay contactor. The communications signaling also tells the car how much current it can draw from the particular circuity; this is either set by the installer or since many EVSEs today only support a single current, their installation manuals tell the installer what kind of circuit breaker needs to be installed for the devise.
The fancy part of the charging circuitry are actually, as you surmise, in the car itself. It converts the AC from the line into the correct DC voltage that the battery pack needs. It is generally custom tailored for the car's particular battery pack. Today, Insolated Gate Bi-polar Transistors (IGBTs) are generally used more than MOSFETs, however, they basically work just as you seem to assume.
I assume that when these devices are selling at rates of hundreds of thousands per year, we'll see the prices drop down to commodity levels. As we saw today (, one of the largest EVSE manufacturers today just announced they've sold 10,000 EVSEs to date. There is still a way to go before they become a commodity.
You're right that one should be able to just plug in to a standard 120 or 240 volt outlet. Tesla does enable one to do that at 120 volts but currently, none of the other manufacturers let you do that. There are, however, portable EVSEs that can plug into standard 120v or 240v outlets. Some geniuses wrote the National Electrical Code (NEC 625) to mandate the safety features that we find in the EVSE for EV charging. There is a lot of debate about whether that was an effort to kill the electric car or just well-intentioned idiocy. There is also a lot of debate as to whether NEC 625 is just a set of guidelines or whether it is mandatory. Large car manufacturers, however, can't really take the risk of something bad happening and courts punishing them not being compliant whether mandatory or not - so we get EVSEs.
I hope this helps answer your insightful questions.

· · 5 years ago

Volt owners desiring faster 200 to 240 volt charging can purchase that round voltec charger (15 amp capability, 14 used by the volt) for $499. I know this unit is incompatible with some EV's but apparently it works fine for the volt. Needs a simple 12-2 w/gnd feed and 20 amp double pole fused or circuit breaker branch circuit. If you are looking for a speedy way to charge your volt I can't think of a cheaper way. Most locales will allow "Saturday Helper" 12-2 w/g Romex.

· · 5 years ago

@Jim M

I'm trying to find one of those 70 amp VersiCharge thingers. Where can I purchase them and How Much? I heard retail $1295 but wonder if I could pick it up from a Siemens Distributor for wholesale. These are in production products? I wouldn't have thought so but do u know differently since you mentioned it in your article?

· · 5 years ago

@Jim M

" ...Leviton, in its Evr-Green line, makes a fully portable 120-volt charger for $950. It features, among other things, a carrying handle and automatic restart if the charge is interrupted..."

What a BARGAIN!!! I wonder if it even has a FLEXIBLE CORD so that we don't have to carry an electrician around with us to hook it up! Very nice of them to include a handle.

· · 5 years ago

Visiting Loew's I saw they have an Eaton RLC 120 volt 16 ampere charger for only $899. An even GREATER BARGAIN than the previously mentioned Leviton Evr Green!

And if 1900 watts is way more power than you need, or can use due to #14 AWG wiring, or is way over the Top compared to what your EV can use, Ex-EV1Driver would want me to mention the 1400 watt Clipper Creek unit is only $695!!! So if you don't need the huge 1900 watts here, and 1400 is sufficient, buy the Clipper Creek unit and save hundred$ over the BARGAIN Leviton unit. According to their website this unit is Guaranteed to work! What a concept!

· · 5 years ago

Responding to clamoring Popular Demand, Clipper Creek has come up with a no button extremely high power 2400 watt 120 volt LEVEL II unit (I think first in the industry!) for only $735 !!!

I thought Buffalo was the only town that still had 110 volt only homes?. I used to know of a few 110 volt only businesses but they are all gone. The website says this is primarily for business use. Must be due to the huge power levels involved.

· · 5 years ago


Actually not to be nitpicky but your caption is wrong. We don't want to confuse the uninitiated.

"....The range of Leviton Evr-Green chargers: 240 volts with portability and a dryer plug for around $1,000. (Leviton photo)...."

The left most plug and template is a 20 amp 2 wire with ground outlet. These have been used around the house for Space heaters, Air conditioners, Shop Tools, and 16 amp (evrgreen 160's) Leviton car chargers but never for home clothes dryers in the US.

The larger charger (and the not-shown 40 amp unit) has a Nema 6-50 ( one used for 225 Amp Lincoln welders) plug

Dryers use either 30 amp Nema 6-30 or 14-30 and the Levitons of any size (16, 32 or 40 amp) can use NEITHER style of dryer plug. Just saving you guys money if you are planning on installing an outlet for these levitons. You can use a 20 amp,(for the 16 amp 160) or 50 amp outlets( for the 320 or the special rav4ev charger dock) ONLY.

Don't worry Jim this MYTH originated with Tesla years ago, and apparently it still persists.

· · 5 years ago


Actually not to be nitpicky but your caption is wrong. We don't want to confuse the uninitiated.

"....The range of Leviton Evr-Green chargers: 240 volts with portability and a dryer plug for around $1,000. (Leviton photo)...."

The left most plug and template is a 20 amp 2 wire with ground outlet. These have been used around the house for Space heaters, Air conditioners, Shop Tools, and 16 amp (evrgreen 160's) Leviton car chargers but never for home clothes dryers in the US.

The larger charger (and the not-shown 40 amp unit) has a Nema 6-50 ( one used for 225 Amp Lincoln welders) plug

Dryers use either 30 amp Nema 6-30 or 14-30 and the Levitons of any size (16, 32 or 40 amp) can use NEITHER style of dryer plug. Just saving you guys money if you are planning on installing an outlet for these levitons. You can use a 20 amp,(for the 16 amp 160) or 50 amp outlets( for the 320 or the special rav4ev charger dock) ONLY.

Don't worry Jim this MYTH originated with Tesla years ago, and apparently it still persists.

· · 5 years ago


Its all made clear in current literature now but originally when SPX came out with their universal slim line EVSE they were calling it a 30 amp charger as you did: "... The cost difference is minimal and the SPX L-2 connector will enable 30 amp charging so it is much more future-proof.
..........". Actually initially I didn't understand this and I called them. I said, since this is a "CONTINUOUS LOAD", how are you drawing 30 amps from a 30 amp plug? They said that they MEANT to say 24 amps when it is on a Nema 6-30, and the unit must be hardwired (modified) if it is to run 30 amps. Persnickety inspectors will then fail the job.

· · 5 years ago

Oops brain fart: "....Dryers use either 30 amp Nema 6-30 or 14-30 ...." from 2 posts back. 6-30 is what the spx express uses, dryers use 10-30 or 14-30. I get thinking about one thing and typing the other thing and the result doesn't make sense sometimes. Sorry for the confusion.

· · 5 years ago

Back to the subject here. I hate to say anything, but, I haven't heard anyone else mention it so I'll do it here...

Jim, you write great articles man, and you're to be applauded for taking on subjects a bit technical. But there is a concept here which everyone doing anything electrical should be aware of.

Please Memorize this chart:

Circuit Fusing and Minumum Circuit Ampacity Maximum Continuous Load


· · 5 years ago

What happened?
Where am I? Ok let's try again. This only applies in Us & Mexico but it is a good idea anywhere.


100 80
50 40
40 32
30 24
20 16
15 12

The issue is a "Continuous Load". EV charging is a continuous load because it COULD take 3 hours or longer. This is so that wiring doesn't overheat. Its not a concern of the National Electrical Code, (because they are solely concerned with SAFETY), but obeying the above chart will also prevent nuisance fuse blowing or breaker tripping.

So what practically does this mean and why is it germaine to this topic? Simply a 30 amp charger (from the chart) must use at least 40 amp circuits, wiring, devices, etc. NOT 30. Also, for years NEC has only recognized 50 amp branch circuits in homes, so for residential use, you probably wont find anything bigger than the Leviton Rav4EV charger (40 amps), or Tesla's mobile connector, or Tesla's model S on a plug any larger than 40 amps loading (all of the above examples using 50 amp recepticals and attachment plugs, fusing, etc). To go bigger in a residence the chargers are hard-wired with no plugs.

· · 5 years ago

@Bill Howland,
While you're technically correct. EVers have traditionally not gotten too upset about that 80% derating on the breakers when referring to a capability. Most of us are happy with 30 amps, whether that really means 32 amps because there's a 40 amp breaker or 24 amps because there truly is only a 30 amp breaker.
As you're seeing with your trip up north, anything is better than a standard 120v outlet for charging. Once you have a choice, of course, you'll take a 32 amp connection over a 24 amp one but, today, we're lucky to find any of these options.
In a lot of cases, the voltage drop on the line due to undersized wiring or 208 volt -vs- 240 volt accounts for a greater percent drop than the 80% current derating.
You'll also find that old, worn, 50amp rated RV outlets often blow if you try to draw 40 amps from them so it is often wise to only try to draw 32 amps or less lest you return to your car 3 hours later to find you haven't gotten much charge.

· · 5 years ago


Its irrelevant whether I'm technically right or not. The 30 amp fuse or 30 amp circuit breaker at a .98 pf 30 amp loading knows nothing about overall voltage drop, nor Brand of Vehicle being charged, etc, and its heating and nuisance blowing will neither be advanced nor postponed by any degree of "EVSE Traditional Upsetability".

Jim is saying in this article that basically the Leviton 320 (32 amp model) is on a 30 amp plug, elsewhere he said its a Dryer Plug.

The Leviton 320 uses a Nema 6-50
A dryer plug is either a 10-30 or 14-30, which neither Leviton 320 nor Leviton 160 can use.

I normally let these details slide, but the article was arranged such that people reading it might go out and start ordering parts that CANT work. Therefore, even though some won't like it, I diplomatically as possible offered a correction.
RE: Tesla Roadster Charging Design Defect, (I'm not offering that for debate since I've measured what is happening), Tesla was very supportive: e.g.
"Jeez we hope you figure it out Bill! Of course if you get stumped, we do have our own products that do work", hehe...As mentioned before Schneider's attitude was much different :" It works with a Volt and Leaf, that's all we're concerned about. Goodbye!.".

Since I was the first customer ever in the Northeast for this product, I relayed the story to the distributor where I purchased it (prior to Lowe's and HomeDepot picking it up), and they screamed bloody- murder at them, saying HOW DARE they treat one of their customers this way, and conveniently mentioned the $million dollars of sales they purchase every year. The application engineer eventually called with his tail between his legs, but after he found I had redesigned the unit, he never bothered to find out the fix, or even the precise initial problem.

· Charlie Barrett (not verified) · 5 years ago

@ex-EV1 driver

Thanks for the Info! If I can find a schematic, parts list and communications protocol spec for one of those Level 2 chargers, I know I can build one myself for a fraction of the cost of one of those $900 chargers. I'm sure the power transistors and any regulator chips required are off-the-shelf devices, or can be re-designed using off-the-shelf devices.

As for the communications with the car, I'm sure software would have to be written, but that is also do-able with a $35 Audreno processor board and an interface circuit.

Of course, it wouldn't save much money if it voids the battery warranty and over-Charges the batteries or something.

· Charlie Barrett (not verified) · 5 years ago

@ Bill Howland,

wow, I've never lived in an area where houses are only wired for 110 volts! You couldn't even have a standard central air conditioning unit or an electric dryer if that were the case. All 220V feeds have 110V to neutral, but the two "hot" wires are opposite in phase, and thus read 220V across the hot wires, not to neutral. I'd be willing to bet that's what you've got. 110V outlets simply use one of the 220V hot lines plus neutral, instead of both hot lines. Usually the electrician tries to balance out the load by wiring some 110V outlets to one of the 220V 2-phase lines, and other 110V outlets to the other side, creating the illusion of only having 110V available.

Even at 10 amps, I'd use 12ga wiring and a 12ga extension cord if required, or better yet, 10ga. It becomes a necessity to use 10ga wire for a 110V circuit if the outlet is located much more than 50 ft from the breaker box with a heavy load. Even though 14ga can certainly handle up to 15a, and 12ga can handle up to 20amps, the voltage drop may be significant for long runs, and thus the charger may not work right.

Motorized equipment like Window air conditioners may even stall and burn up or may just slow down, draw excessive current and overheat on long runs unless 10ga wire is used for anything more than 10amps.

· · 5 years ago

@Charlie Barrett

Umm the short answer is you'd bet wrong. There at one time were many houses in this area that use a 2 #8 AWG wire service They are getting pretty rare but you still do run into the occassional one. Usually 30 amps @ 120 volts. The worst thing from a capacity viewpoint I've seen has been a 1931 5000 square ft 4 unit appartment building with Centralized SO2 Refrigeration (Carrier developed Freon with DuPont that year).
5 meters each with 30 amp mains, and the main feed was 2 #8 AWG R's. The fifth meter was the house meter, running the free refrigeration, hallway and basement lights, and Coal Stoker.

Of course, today those existing loads are fed by a 120 / 240 volt single phase system by the utility (for our European readers, the 120 volt loads are essentially every other circuit, in this case every other house, is in series with each other - its not called 2-phase since the phase angle is a trivial 180 degrees, and is fed by one source in any event which is impossible to do if there were the typical 2 phase 90 degree phase angle).

However, there were many large theatres that were fed with 2 wire 600 or 800 amp services and the serving transformer was a 1 coil secondary 120 volt only and there was no "neutral" anywhere.

IF you're interested I can also talk about 120 volt 3 phase
Electric Services and motors, 25 hz, corner grounded or grounded "b" services, Double voltage double 3 phase Delta services, 4 wire open and closed Delta, and these days the most common Y or open Y 'single phase' services which are common in NY City.

· Shinnlinger (not verified) · 5 years ago


Wife just leased a leaf and we are impressed with the car, not as impressed with the 120 recharge time. Like others here, I cannot believe 240 units are not supplied with each car (there trying to make them more drivable right?) and find it absurd the amount of money that has to be shelled out for a home 240 system but now appreciate the reason for it has to do with liability and inspectors.

Where we live, however, inspections are not applicable and I would feel very comfortable installing a hardwired charging unit. As I understand it, the Leaf has the inverter built into the car and can magically tell how many volts are coming in and deal with it accordingly.

Couple of scenarios I wonder about:

If you could acquire a J1772 plastic nozzle (where)?) and simple wired it up with some heavy wire to a 30/40/50 amp breaker what would happen? The car is only going to draw what it needs in theory but would it work that way or be really stupid? what if you put an inline fuse in first?

I also wonder about getting a male welder plug and basically wiring it a HD female 120 plug and plugging my homemade adaptor between one of my welder outlets and the supplied nissan 120 cord. BAd idea? This seems to be what Tesla is offering?

So like I said before. Inspections are irrelevant but I don't want to blow the car up.



· ronald doctors (not verified) · 5 years ago

Been using my own cable mod for 18 months with no problems.. Charges on either 120 or 240... it is a very simple mod. The argument that the cable must be permanently attached to 240 is stupid since every buiilding site has 240 volt extensions all over the place. And in UK and other countries they only have 240 volts!! Come on....the NEC gets in the way of common sense and to say there is a fire risk just shows how ignorant the writers are. The cable suplied by leaf is rated at 240 volts BTW!!!

· · 5 years ago


No easy answer here. Voltec $499 15 amp unit @ 240 volts would satisfy your needs, but is only available for volt owners.. If you have a friend or acquaintence with a Volt you can order through him... Otherwise, Lowe's and Home Depot offer $799 Schneider electric 30 amp model (you can only use 14 amps of this, but if you purchase another car in the future that can go 30amps then you will be future proofed.

Installation: If 16 amps is the most wanted, use 12/2 cable, either NM (romex), UF, BX, or MC, or for a deluxe job wiremold 500 , or EMT or Rigid Galvanized Steel.

If 30 amps wanted use 8/2 .
20 amp breaker for 16 amps max, 40 amp breaker for 32 amps max, both double pole. If you have a fuse box with 2 poles spare, use either 20 or 40 amp fusing. This also applies to power take off lugs. Obviously you must measure 200-240 volts between 'poles'. Hope this helps.

· · 5 years ago

@Ronald Doctors

Actually, not sure if you meant to say this, but an EVSE is not required if you have a ground fault and its 120 volts at 16 amps or less..

I'm against requiring an EVSE (Tesla's have essentially an EVSE in their UMC), but residential branch circuits can be as large as 50 amps. The only (other than the Tesla old and new UMC cords) mfgr to utilize this to my knowledge is the LEVITON brand charger optionally available with the Toyota Rav4EV.

It has 40 amps output and plugs into a 50 amp 6-50 (welder plug 2 wire plus gnd) outlet.

THE NEC (National Fire Protection Association) is not as perfectly objective as they claim. All those improperly wired aluminum homes in the 60's and 70's burned down, and there was nothing in the NEC at the time stating any special care re: aluminum wiring. (there is now). The manufacturers quietly pulled AL romex off the market, including the Perfectly Safe, inexpensive Copper Clad AL, which no-one ever used (except me, hehe).

When you look at all the Aluminum Companies on the 'advisory board' of the NEC at the time, it all begins to make sense.

Same with EVSE's. Its just a way for electrical equipment manufacturers to see more 1000% markup unnecessary junk.

· Shinnlinger (not verified) · 5 years ago


How did you do your mod? Is it the $10 ebay book?
I would be comfortable with that type of mod because the car will only daw 16 amps so the stock cables will hold up fine. Was it an easy thing to do/revert back? The car is leased so I don't want o do anything permanent.


Why do they only sell that to volt folks? Crazy to me....



· · 5 years ago

The $499 Voltec is probably subsidized by GM today.
While I can certainly see EVSEs costing $500 or less once volumes rise, I suspect that it is hoping too much to expect the prices to drop too soon.

· Tony Williams (not verified) · 5 years ago

Some of you folks may be interested in the "OpenEVSE" projects. Basically, a microprocessor, a small relay, a bit relay, a display, and the box and wiring.

You build it yourself. I did a 75 amp version for about $550. You could make a 16 or 30/32 amp version for slightly more than half that cost.

I also modified an old Mini-E / Clipper Creek unit to work at 40 amps with my Rav4. Clipper Creek actually sells a kit to convert these to 30 amp units for about $500, but I used the ITT 75 amp cable and reflashed the "motherboard" to send a 40 amp pilot signal. The relay is 65 amp rated, so I could have flashed the card up to 60 amps. Of course, that would require an 80 amp breaker and I don't own a car currently that needs 60 amps.

· · 15 weeks ago

Electric plug car is very good for enviroment, choose electric cars is protect our home in the world.


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