[Fabulist]

The last couple of post in this thread deserved a lot of attention, IMHO because it answered a heavily debated question about the convenience charger that comes with the Karma, but for some reason went unnoticed, so I am starting a new thread to make sure it gets the attention it deserves.

Early on, we had spent some time discussing whether Fisker makes different versions of the convenience charger that comes with the car or if they just make one version of the device that can adapt itself to the local voltage, like practically every other electronic device sold today. See this thread, for example.

Ultimately, the discussion faded out because short of taking a US Spec. charger and plugging it into a 220V plug it was not really possible to make a conclusive determination one way or another, and understandably, no one was prepared to conduct this experiment.

Well our fellow forum member @EVO-Z finally conducted that experiment, out of sheer necessity. What happened was that he bought a car in the US and had it shipped to China where the local voltage is 220V. By the time the car arrived, cleared customs, and he took delivery, the HV battery was dead and he could not even start the ICE to charge the battery and he could not easily locate a J1772 compatible EVSE locally. After exploring various suggestions by the members of this forum, he obtained a plug adaptor for the US plug (not a transformer or voltage regulator, just a plug adaptor) and plugged the US Spec. charger into the local grid, and lo and behold, the adaptor worked just fine with 220V.

Now I am not recommending that anyone do this and I accept no responsibility for any damage caused by doing this, but if the information is correct and EVO-Z is in fact using a US Spec. charger, it should be possible to use an adaptor (such as the one suggested by @Siliconkiwi here) to plug the convenience charger into a dryer (or similar) plug to charge the car a lot faster without having to spend a lot of money getting a standalone Level II charger installed.

Of course, this is too late for me because I have already installed a Blink charger in my garage, but others may consider investigating this further, and it implementing such a solution, as long as it turns out to be safe and legal to do so.

 

[ct-fiskerbuzz]

It should work fine. But we should also note that US 240-volt dryer-style outlets are not made for repeated daily plug/unplug cycles. They are designed with the thought in mind that you will plug in an electric dryer, and then leave it in for years, and then unplug it, so that over the course of a few decades it will have things inserted and removed maybe a dozen times at most.

(One of the more expensive individual parts of the charging plug—the funky plug at the end of the convenience charger, that goes into the Karma—is the construction quality that allows you to plug it in and pull it out at least once a day for many years. That gets left out of 240-volt dryer sockets, to make them cheaper, on the theory that it's not needed.)

 

[Weird Fishes]

When electricity is the issue in question, I tend to become very, very, very conservative. After all, the last thing I need is to get electrocuted.

And when the issue in question is electricity and our Fisker Karmas, I think we should advocate being as safe and conservative as possible. After all, the last thing Fisker needs is for Jalopnik to print a sensationalist (and probably inaccurate) story about a Karma or it's owner getting fried because they were using the wrong current/electrical setup/charging station/etc...

 

[Makis]

Go to www.FiskerAutomotive.com and click on First Responder.

Also the How-To video link on the Website are very cool. http://www.youtube.com/user/KarmaOwners.

Thanks lots of useful info
The YouTube video on charging the Fisker states the charger provided with the vehicle is a 220 Volt.
My Fisker came with a standard 120 Volt three prong cable. Can a standard 125 to 220 volt adapter be used like the ones available at Radio Shack be used to plug into a 220 volt receptacle? has anyone tried this?

 

[Fabulist]

Thanks lots of useful info
The YouTube video on charging the Fisker states the charger provided with the vehicle is a 220 Volt.
My Fisker came with a standard 120 Volt three prong cable. Can a standard 125 to 220 volt adapter be used like the ones available at Radio Shack be used to plug into a 220 volt receptacle? has anyone tried this?

See the posts above and also in the thread linked in the first post.

 

[NJFISKERGUY]

I just want to make sure I understand what you are saying. If I change the plug on my charger from 110 to 220 plug I can charger my car at the faster rate? Of course pluging it in to a 220 outlet..

 

[Ira]

I just want to make sure I understand what you are saying. If I change the plug on my charger from 110 to 220 plug I can charger my car at the faster rate? Of course pluging it in to a 220 outlet..

I'll stick in my 2 cents here.

The Lear charger spec is 85VAC to 265VAC. Yes, it will charge 2x faster at the higher voltage. However, 220VAC is lethal. A safer approach than using an adapter is to have an electrician rewire the Lear with a 220VAC pigtail.

Also, don't ever use an extension cord when plugged into 220VAC.

 

[NJFISKERGUY]

Hummm that's very interesting information. For some reason I thought that the plug used different pins on the charger handle. I did buy a 220 charger could not wait 12 to 14 hours to get my baby back on the road.

 

[Harleyguy]

I'll stick in my 2 cents here.

The Lear charger spec is 85VAC to 265VAC. Yes, it will charge 2x faster at the higher voltage. However, 220VAC is lethal. A safer approach than using an adapter is to have an electrician rewire the Lear with a 220VAC pigtail.

Also, don't ever use an extension cord when plugged into 220VAC.

With proper rated wiring you can use an extension cord I use one to backfeed into my house when using my generator . The cord is about 10 feet long

 

[Ira]

Not everybody is Harleyguy.

 

[ebarneyr]

Go to <www.evseupgrade.com> . I bought the 220v 16 amp with pigtail for 120v and while pricey, it works great.


Sent from my iPad using Tapatalk HD

 

[Fabulist]

With proper rated wiring you can use an extension cord I use one to backfeed into my house when using my generator . The cord is about 10 feet long

The other option is the extend it from the car connector end, with a J1772 extension cable, like the one discussed in this thread:

I use this one every day to charge my car because the L2 charger at our office is not optimally located for the Karma. It is rated at 45A and can easily handle the 16A draw the Karma uses to charge.

 

[P90XMC2]

So I'm not sure I got this right,

The charger that comes with the car works with 220v although its not rated to do that,
Now, does the car get charged the same way as any L2 charger would charge it - 220v 16amp or it just adjust the 220v to 110v and then puts 16amp for that voltage that gets you 1.6kwh which is L1 charge?

Can anyone tell?
What charger does the european cars comes with?

From what I've seen on the accessories site for Fisker, they do have a L2 portable charger but its a branded Clipper Creek one.


Sent from my iPad using Tapatalk HD

 

[marswill]

I met an BMW EV owner (actually you can only lease the BMW EV) the other day and we compared his BMW to the Karma. The BMW is really a modified BMW and a prototype. The point I want to make it that it appears his charger is identical to the one that comes with the Karma. He said that he has used it on 220V.

 

[Fabulist]

So I'm not sure I got this right,

The charger that comes with the car works with 220v although its not rated to do that,
Now, does the car get charged the same way as any L2 charger would charge it - 220v 16amp or it just adjust the 220v to 110v and then puts 16amp for that voltage that gets you 1.6kwh which is L1 charge?

Can anyone tell?
What charger does the european cars comes with?

From what I've seen on the accessories site for Fisker, they do have a L2 portable charger but its a branded Clipper Creek one.


Sent from my iPad using Tapatalk HD

I think the portable charger draws the same amperage whether on 110v or 220v (13A). Obviously, at 220V you are drawing twice the KW at the same current and your car can charge twice as fast. It seems logical that the portable charger can work at 220v or 110v so that it can be used around the world, but I would be concerned about the cord between the wall plug and the charger, since the American version only needs to handle 13A at 110V and if you draw the same 13A at 220V, there is a risk that the American cord could overheat or even start a fire. The European charger is the same box but the cord connecting the box to the wall socket seems beefier.

From the charger to the car, I would think the connections would be identical.

 

[marswill]

On 220V the current is the same, only the voltage is doubled which cuts the charge time in half. The charger is not like a resistor which would double the current if you double the voltage quadrupling the wattage. The Charger is more of a constant current device. Therefore the wires will see the same current irrespective of the voltage.

 

[ct-fiskerbuzz]

I think the portable charger draws the same amperage whether on 110v or 220v (13A). Obviously, at 220V you are drawing twice the KW at the same current and your car can charge twice as fast. It seems logical that the portable charger can work at 220v or 110v so that it can be used around the world, but I would be concerned about the cord between the wall plug and the charger, since the American version only needs to handle 13A at 110V and if you draw the same 13A at 220V, there is a risk that the American cord could overheat or even start a fire. The European charger is the same box but the cord connecting the box to the wall socket seems beefier. ...

Although I have not opened up the "convenience charger" to look inside, it's pretty obvious what's in there: a small board that monitors the power connection and sends the negotiation signals to the J1772 plug (the big round one that goes into the car), and a relay that connects / disconnects the wall-socket-side power line to the car-side power line. (The J1772 connector, which has more than just the power and ground pins, is basically your "power and ground" pins plus those negotiation signals.)

Here's what's slightly wrong in the quoted bit above: the amount of current a wire can carry without overheating is the same regardless of the voltage. Power dissipation in an ideal resistor [1] is simply "I-squared-R": the square of the current (13 amps) times the resistance (ideally, much less than one ohm). That means the power dissipation in the wires is less than 13-squared (169 amps-squared) times, say, 0.05 ohms, giving something under 9 watts. That dissipated power turns straight into heat. [2]

The power delivered to the device (car, in this case) is simply voltage-times-current. Let's say current is always exactly 13 amps. [3] The more you raise the voltage, the more power is delivered to the car. The current is always 13 amps, and the resistance "R" value is the always the same (let's keep using that 0.05 number), so at 1 volt, you deliver about 13 watts [4] and waste (as resistive heating) something under 9 watts. At 10 volts, you deliver 130 and waste 9. At 100, you deliver 1300 and waste 9. At 120, you deliver 1560 and waste 9. At 240, you deliver 3120 and waste 9. See where this is going?

It would make all kinds of sense to use, say, 100,000 volts, which would deliver 1.3 megawatts and waste that very same 9 watts. Except for one big problem: the higher you make the voltage, the more eager the electricity is to "squirt out" across things that look like insulators: rubber wire covers, air, and so on. (And a smaller but still significant problem, the Karma will only accept power at 3.3 kW, same as the original Leaf and where a lot of the early Level 2 chargers maxed out. Some EVs now take 6.6 kW, and the Tesla S will take up to 90 kW.)

Still, the key take-away here is that power loss rises (squared!) with current, and power delivery rises (linearly) with voltage. This is why the big transmission wires you see along the freeway use 360 or 720 kilovolts: lots of power delivered using as little current as possible. But it's stepped down (to 13 kV and 480 volts and so on) for more-local distribution because that's less "squirty" and therefore does not have to be handled as carefully. If you look closely at high tension power lines, you'll see massive insulators separating the wires from the towers that hold them up. Look at local distribution lines and the insulator stacks are much shorter.

Now, back to your 120 or 240 volt stuff: the first important point here is that neither the "convenience charger" nor a "level 2" charger does any real converting, it just feeds the raw volts-and-amps through to the car. All the "smart" electronics are on the car! So from the car end, it's perfectly fine to plug the convenience charger into 240 volts. The wires won't overheat because you'll send the same 13 amps in all cases. The key question is not heating, but rather, whether the 120-volt convenience charger's wires are insulated well enough to keep a 240-volt-pressure wall connection from "squirting out" and making a short-circuit (and hence causing a fire, etc).

Footnotes:

[1] Wire isn't technically an ideal resistor (it has a little bit of capacitance and inductance) but it's close enough for our purposes. (Also, the resistance of a wire is normally pretty negligible, unless/until you get corrosion or metal fatigue or similar. That last part is very important, especially since that increases the resistance which causes localized heating which itself also increases resistance, in a very bad feedback loop.)

[2] Touch a "wall wart" power adapter for some device, like a cell phone charger or answering machine or whatever, that has been plugged in for a while: it will feel slightly warm; that's dissipated (wasted) power in the wall-wart. Incandescent bulbs waste most of their power: 60 or 75 or 100 watts, less than 5% of it becomes light and 95+% is dissipated, which is why they get so hot. You can actually tell if one power adapter is more efficient than another by which one stays coolest.

[3] This glosses over a big complication: it's the car's charging circuit that makes sure that "current" stays constant, in cooperation with the signals over the "signal" part of the J1772 connector. Basically the charger tells the car "you may have 13 amps" or "you may have 10 amps" or whatever number, and the car makes sure to stay right around that point or less. Otherwise we'd get to footnote 4, which is...

[4] Power lost via I**2R losses also lowers the voltage at the device which in turn limits current further, so at 1 volt you wouldn't actually deliver 13 and waste 9. In fact, I suspect the circuits wouldn't even power up at that point. Still, the general idea applies: more volts = better power delivery, but also more danger. In the case of these car chargers, though, the battery charger circuit dynamically fiddles with the car's "R" resistance value to keep the current at 13-or-so amps, unless that's more than negotiated or needed. Meanwhile, the box at the plug end of the convenience charger monitors voltage there, and asks the car to turn down its charge rate if the voltage it sees drops below some critical number, probably around 105 volts. That's why the convenience charger is supposed to be used by itself: if you put a lot of things on an extension cord, and some of them use a lot of power, they drag down the voltage available to other devices. If you have a very long extension cord, it adds its own resistance, dropping the voltage that the convenience charger sees, and so on.

 

[marswill]

ct-fiskerbuzz, your explanation above is excellent. In regards to the wiring handling the voltage due to potential insulation breakdown it should be realized that in the US, 240 volts is actually 2 phases of 120V referenced to the neutral (which is near ground potential). The 2 phases are out of phase with each other thereby providing 240V across them. This means that the highest voltage from any conductor relative to ground is no higher than 120V. Of course the wiring insulation has to handle the 240V between the two phases but as each wire is insulated to handle at least 120V safely the combined insulation of the two wires (phases) can safely handle the 240V. In the case of 240V operation, the neutral conductor used for 120V operation is replaced by the second phase thereby providing 240V.

The only issue is if the electronics in the charger can safely handle the 240V. The wiring should not be an issue.

 

[ct-fiskerbuzz]

Another side note: the 240 volt power coming off the wires feeding the house is actually a single phase on "3 phase" AC power, but it's coming off a center-tapped transformer link, with the center wired to the house's neutral/ground. So it is also "two phases" of 120 volt power 180 degrees out of phase, giving you both 120 and 240 volt power.

If the neutral line gets disconnected it's possible for the house neutral to float off the desired "0 volt" potential and hence for one leg of the "120 volt two phase" power to climb towards 240 volts, with the other leg climbing down. This is rare (and dangerous for old 120-volt-only appliances) but I guess it figures into electric code wire-insulation levels? (I only know electrical theory, not the practical stuff. )

Apartment buildings are often on true 3-phase power, with 120 volts across a phase and 208 volts (rather than 240) across any two phases.

Anyway, modern power electronics almost always has a range of ~100 to ~250 volts, and 50-to-60 (or wider) Hz, AC input, because it's cheaper to manufacture one design to be used in Europe (50 Hz 220-to-240 volt) and North America (60 Hz 120 volt) and for that matter the rest of the world (mostly the same as Europe), than to manufacture different designs for different locations.

 

[Harleyguy]

At this point I'am totally lost what the whole discussion was about lol . If anyone wants a picture of the inside of the 110 charger that comes with the car I will post it .