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Discussion Starter #1 (Edited)
Hi there! ;)

I have a simple question. Assuming the in-car charger is 3,3kw (3300w) max rated, can I buy a 3kw (3000w) transformator from 110v to 240v !?

This way, I just buy a LCS-25 to be able to bring the power to the car and thats it!? Plus, I can bring the transfo with me everywhere where there is 110v and charge the car faster !?

In fact:
Plug the 110v to 220v transformator into the wall which supply 3000w;
Plug the LCS-25 to the transfo;
Plug the LCS-25 to the car.
And there I go!

Thanks!
 

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If you buy a level 2 EVSE, it must be hard wired (an electrician job) to your breaker box. No big deal - costs less than messing with transformers. And at 27.5A that is a very high draw across a 120V line. Do it right and talk to an electrician.
 

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In theory, it can be done. However, you'd want a bigger transformer - the car will try to draw more than 3kW, and some (many?) transformers are listed by surge ratings rather than continuous.

Bringing it everywhere isn't going to help as much as you're thinking. As Bonaire points out, you'll likely be drawing close to 30 amps on the 110V line - which is far more than the standard 110V line, outlet, and breaker are rated for. You'd need special dedicated high current wiring and outlets to handle the power - at which point I'm not sure I see any benefit over more common high power 220V wiring (like electric clothes dryers outlets.)
 

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If you buy a level 2 EVSE, it must be hard wired (an electrician job) to your breaker box. No big deal - costs less than messing with transformers. And at 27.5A that is a very high draw across a 120V line. Do it right and talk to an electrician.
I thought there were some (a few?) Level 2 charges that are portable. You need only wire an outlet back to your breaker box and simply plug the EVSE into it?
 

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Discussion Starter #5
Mmm yes actually I made a mistake. I said LEVEL 2 EVSE which is a charging station. I was more talking about a portable EVSE such as the LCS-25.

Plug the 110v to 220v into the wall;
Plug the LCS-25 to the transfo;
Plug the LCS-25 to the car.

I'll modify my thread
 

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Theoretically it could be done, but practically, not really. You can use a transformer to bump 120V to 240V without a problem IF you are using low amps. 3.3kw at 120V will draw nearly 30A. That would mean you need a 40A single pole breaker and the appropriate wiring. I'm not even sure you can buy a 40A single pole breaker.

You are much better off just running a 240V wire from the breaker to the location you need to plug in.
 

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Discussion Starter #7
Theoretically it could be done, but practically, not really. You can use a transformer to bump 120V to 240V without a problem IF you are using low amps. 3.3kw at 120V will draw nearly 30A. That would mean you need a 40A single pole breaker and the appropriate wiring. I'm not even sure you can buy a 40A single pole breaker.

You are much better off just running a 240V wire from the breaker to the location you need to plug in.
Yes I understand to get 240v at home and just install a EVSE level 2. But the main goal is to get a faster charge everywhere I go with 110v.

I understand you meaning with the 120v * 30A = 3600w but the transformator is there for that.. transform 120v @ 12A (HydroQuebec here give max 12A), to 240v @ 15A = (3600w exemple)

So:
I cannot have more than 12A.. thats then impossible to have 120v @ 30A

If you ask an electricien to install 240v to the house, thats an other thing.. now you can have more output A
 

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transform 120v @ 12A (HydroQuebec here give max 12A), to 240v @ 15A = (3600w exemple)
That's impossible. To get 15A @ 240 volts out will require 30A @ 120V in. That's just the physics of transformers. If you somehow current limit the input to 12A @ 120V, the max output would be 6A @ 240V. There is no free lunch. :)
 

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Realistically, you'll never find a "standard" 115 VAC outlet in the wild rated to deliver 3.3 kW of power. Typically, you could get about 1,750 watts and at best 2,300 watts before tripping the breaker. The basic electrical formula for electric power is P = V x A, or power in watts = volts x amps. Almost every 115 VAC circuit with a "standard" plug outlet is rated for at 15 amps, with either a 15-amp or 20-amp circuit breaker . This means that a 115 VAC plug-in receptacle AT BEST can provide between:

115 x 15 = 1725 watts
to
115 x 20 = 2300 watts

before the circuit breaker will sense an overload and trip out. Basically, your idea of a 120/240 VAC boost transformer with 3.3 kW 240 VAC EVSE will not work, as the Volt internal charger will sense that it is connected to a 3.3 kW 240 VAC EVSE and will think it can draw up to 3300 watts. This will draw 3,300 / 115 = 28.6 amps on the 115 VAC circuit connected to the 115 VAC side of the boost transformer. This will trip the 115 VAC 15 or 20 amp circuit breaker every time.

With the Volt's standard (and no-cost) 115 VAC portable EVSE, you can set the Volt to either an 8 amp or a 12 amp charge rate. At 12 amps, it will deliver 1,380 watts. Keep your life simple and live with it if 115 VAC is all you have.
 

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Plug the 110v to 220v into the wall;
Regardless, the answer is NO.....for all the reasons given, the most important of which is that the 110 V. side of the circuit will NOT sustain that much current (or power, if you want to look at it that way).

That is the WHOLE reason for moving up to a 220 V feed in the first place.
 

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Yeah, that's not going to work for a "faster charger everywhere you go" kind of thing. That's WAY too much current pulled on a 110V line out and about. You will never come across a 110 line out in the world that can handle that much current. It sounds like it could work but in practice anywhere you plug that setup into, would blow circuits, melt wires, melt receptacles and cause problems.

You won't find faster charging "out and about" unless you find a dedicated 240V plug (public charging station, RV park, garage with welding plug, etc). I have a "portable LCS-25" that I keep in my car and my office ran a dedicated 240 circuit. I wired one up at my mom's house. So I can have faster charging the places I go most frequently.
 

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There is no free lunch. :)
I don't know, I used to drive a Crown Victoria with steel wheels, antennas and a push bar (as I was working as a software engineer) and when restaurant employees saw my car I got "Is that your car? Yes? Then the meal is on us." Must be a lot of people who are Crown Victoria fans.
 

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I don't know, I used to drive a Crown Victoria with steel wheels, antennas and a push bar (as I was working as a software engineer) and when restaurant employees saw my car I got "Is that your car? Yes? Then the meal is on us." Must be a lot of people who are Crown Victoria fans.
Either that or they were mesmerized by your mirrored aviator shades. :)
 

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Discussion Starter #14
That's impossible. To get 15A @ 240 volts out will require 30A @ 120V in. That's just the physics of transformers. If you somehow current limit the input to 12A @ 120V, the max output would be 6A @ 240V. There is no free lunch. :)
I understand but your totally wrong. A friend of mine bought this http://www.quick220.com/220_catalog/20-ampere-systems.html

This can be plug into ANY 110v ... and they have normal 12A output max by our country. And that give 240V @ 15A.. which give 3600w output.

Realistically, you'll never find a "standard" 115 VAC outlet in the wild rated to deliver 3.3 kW of power. Typically, you could get about 1,750 watts and at best 2,300 watts before tripping the breaker. The basic electrical formula for electric power is P = V x A, or power in watts = volts x amps. Almost every 115 VAC circuit with a "standard" plug outlet is rated for at 15 amps, with either a 15-amp or 20-amp circuit breaker . This means that a 115 VAC plug-in receptacle AT BEST can provide between:

115 x 15 = 1725 watts
to
115 x 20 = 2300 watts

before the circuit breaker will sense an overload and trip out. Basically, your idea of a 120/240 VAC boost transformer with 3.3 kW 240 VAC EVSE will not work, as the Volt internal charger will sense that it is connected to a 3.3 kW 240 VAC EVSE and will think it can draw up to 3300 watts. This will trip the 115 VAC 15 or 20 amp circuit breaker every time.

With the Volt's standard (and no-cost) 115 VAC portable EVSE, you can set the Volt to either an 8 amp or a 12 amp charge rate. At 12 amps, it will deliver 1,380 watts. Keep your life simple and live with it if 115 VAC is all you have.
Thanks for the formulas.. but I already know them lol. Cmon. Indeed thanks for the details..

Please read what I said to the other guy please.
 

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I understand you meaning with the 120v * 30A = 3600w but the transformator is there for that.. transform 120v @ 12A (HydroQuebec here give max 12A), to 240v @ 15A = (3600w exemple)
First of all, I love the word transformator.

Apart from that, what you're describing violates the laws of physics. You can't use a device to double the amount of power coming from an outlet. P = I*V. If you double voltage, current has to drop by at least half.


That said, even if you had a high enough current on the 120V line, I'm not sure it would work anyway. I'm not an electrician, so maybe I'm wrong on this, but a 120VAC line has 1 "hot" and 1 neutral. The hot oscillates at 60 hz. On a 240VAC circuit, there are 2 "hots" -- both still 120VAC, but on opposing phases -- and 1 neutral. So I don't think that simply doubling the voltage of a single 120VAC phase line would work with a 240VAC device.
------------------------------------------------
Edit: The next post clarifies how this can work in reality, with 2 separate 120V inputs. Live and learn.
 

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I understand but your totally wrong. A friend of mine bought this http://www.quick220.com/220_catalog/20-ampere-systems.html

This can be plug into ANY 110v ... and they have normal 12A output max by our country. And that give 240V @ 15A.. which give 3600w output.
That device is kind of cute, and yes it does what it says. But what it's doing is plugging into 2 different 120V plugs to combine them and give you 240V. And yes, you could probably use one of these, but you would have to find 2 120V plugs that were on 2 different circuits. I'm assuming that box has enough smarts in there to make sure the 2 120V hot leads it's seeing are on 2 different phases which means they have to be on 2 different circuits. I think I would be hard pressed to find 2 plugs in my house, that are close enough for this to be plugged in that were on 2 different circuits.
 

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I understand but your totally wrong. A friend of mine bought this http://www.quick220.com/220_catalog/20-ampere-systems.html

This can be plug into ANY 110v ... and they have normal 12A output max by our country. And that give 240V @ 15A.. which give 3600w output.
I found this on their page (I was right about my assumption):
** Note: The Quick 220 Power Supply uses two outlets from two different circuits that are out of phase and not controlled by ground fault interupters (GFI's). The Quick 220 Power Supply has built in circuitry to test for the out of phase circuits. A separate tester is supplied to check the outlet for a GFI. Most buildings have numerous outlets that meet these two requirements.


Yes, this in theory will work, and you could probably plug an LCS-25 into it and hope that the Volt would limit the current out of it. But if you ever plugged that contraption into a car that would pull more juice, it would trip something (the LCS-25 being able to charge at 25 amps or so). But the big problem is finding 2 plugs close enough to each other that are on 2 different circuits.
 

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I understand but your totally wrong. A friend of mine bought this http://www.quick220.com/220_catalog/20-ampere-systems.html

This can be plug into ANY 110v ... and they have normal 12A output max by our country. And that give 240V @ 15A.. which give 3600w output.
First of all I am not wrong. Please review transformer theory. Secondly, that power supply you linked to is not a transformer it is a switching power supply but it cannot increase the available power, meaning the power output must be the same as the power input. Anything else is impossible. To get their listed performance you must plug it into TWO different 120V circuits that are fed from opposite sides of the 240V main, so in effect you are feeding it 240V. It then uses that input voltage, combines it and regulates it to create the output. A clever device but it will not do exactly what you have in mind unless you get lucky enough to access to the correct two separate 120V circuits.
 

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First of all I am not wrong. Please review transformer theory. Secondly, that power supply you linked to is not a transformer it is a switching power supply but it cannot increase the available power, meaning the power output must be the same as the power input. Anything else is impossible. To get their listed performance you must plug it into TWO different 120V circuits that are fed from opposite sides of the 240V main, so in effect you are feeding it 240V. It then uses that input voltage, combines it and regulates it to create the output. A clever device but it will not do exactly what you have in mind unless you get lucky enough to access to the correct two separate 120V circuits.
I'm not trying to say you are wrong. :) Because you are right about all that..... but I'll bet that device is much simpler than that. I'll bet that there is some circuit that can measure the 2 incoming hot leads, and can tell if they are on different circuits. And if they are, and only if they are, there are a couple high power relays that connect those 2 different hot leads to the output on the other side of the box, effectively making a 240V circuit. Only difference between this and a person wiring up an LCS-25 to two 110V plugs is the smarts to make sure you don't power the 240 if it finds they are both on the same phase.
 

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I understand but your totally wrong. A friend of mine bought this http://www.quick220.com/220_catalog/20-ampere-systems.html

This can be plug into ANY 110v ... and they have normal 12A output max by our country. And that give 240V @ 15A.. which give 3600w output.



Thanks for the formulas.. but I already know them lol. Cmon. Indeed thanks for the details..

Please read what I said to the other guy please.
That's actually not a transformer of any kind, and it doesn't create power like you seem to think. The power delivered to US households is what they call split phase 220V. That is, you get three wires from the power company (plus a ground.) Two of those wires go from -~170V to ~170V and back 60 times a second (thus giving 110V RMS AC power @ 60 Hz,) while the third is a neutral return wire.

The thing is, the two wires have opposite timing - so something connected across the pair sees 220V RMS (~340V peak to peak) at 60 Hz, while something connected to either power leg and the return sees 110V RMS.

Standard appliances are plugged into one or the other hot leg and the return (110V) while high power devices are connected to the two hot legs (220V.)

All the Quick220 does is convert plugs - it takes the hot line from two standard NEMA 5-15 outlets and puts them on the two hot legs of a 220V outlet. If the two circuits you picked are both on the same side from the power company, it doesn't work - the 220V device sees no power because both sides move together. If the circuits are on opposite sides, you get 220V power - exactly the same power that was already at the power panel, and the same as a 220V device wired from the beginning to be that. No magic, no extra power.

The laws of physics as we understand them prevent you from pulling the rabbit out of this hat...
 
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