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Discussion Starter #1
I bought this on ebay.

Somebody figured out how to get all the stuff in the bulky boxes of other EVSEs to fit right inside the handle of the J1772 connector! This makes level 2 charging at work (with an adapter for 208V 3-phase) or at a friends house (with an adapter for the dryer plug) really easy.
Being European, this one only works at around 230V. but they are working on a new version that can do 120V also. That will be the ideal replacement for the smart stock level 1 cord: it can do all that the stock brick can, plus level 2 with the appropriate adapters! And it will fit in the same space with a good set of plugs going where the brick used to be.
 

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I bought this on ebay.

Somebody figured out how to get all the stuff in the bulky boxes of other EVSEs to fit right inside the handle of the J1772 connector! This makes level 2 charging at work (with an adapter for 208V 3-phase) or at a friends house (with an adapter for the dryer plug) really easy.
Being European, this one only works at around 230V. but they are working on a new version that can do 120V also. That will be the ideal replacement for the smart stock level 1 cord: it can do all that the stock brick can, plus level 2 with the appropriate adapters! And it will fit in the same space with a good set of plugs going where the brick used to be.
The only 'problem' with 110V as it draws twice the current... That isn't insurmountable, but it does mean that heavy-duty wiring will be needed -- heavier than the original..
 

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Discussion Starter #3
The current can be set to 6, 10 or 16A on the J1772 plug. Supply voltage has nothing to do with that. 120V just means half the power at the same current. The car won't draw more than 16A anyway.
 

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The current can be set to 6, 10 or 16A on the J1772 plug. Supply voltage has nothing to do with that. 120V just means half the power at the same current. The car won't draw more than 16A anyway.
my assumption is that you would want to charge at the same rate. As you pointed out at half the voltage and the same current the power would be half. If it woun't draw more than 16A, the the charge rate would be 1/2 at 110V. Either way, something has to give.:nerd:
 

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my assumption is that you would want to charge at the same rate.
Yup. What the car is actually pulling is best measured in Watts/hour. The charger in the smart ED is limited to 3.3kW/h. Since Watt=Votls*Amps, at 110, the max draw would be 30A. The max draw for 220 would be 15A.

In reality, you'd probably want the circuit (wiring and breaker) to be slightly higher than that, since the wire itself can cause some resistance. Most suggest wiring/breakers for 5A to 10A higher than the expected usage. Most US homes have circuit breakers that will trigger long before the wiring gets warm enough to cause a problem.

There are already a few models of EVSE out there that can tolerate 90 to 240V, ranging from 8A to as high as 40A. (The Power XPress being one example, with about the same foot-print/box-size as the smart ED mode 1 charger, just thicker wiring.)

The one in your picture looks like it would be able to handle more than the smart could draw, even at 220V. Just have to make sure the socket you plug it into can handle the current level you set on the device.
 

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Discussion Starter #6
Yup. What the car is actually pulling is best measured in Watts/hour. The charger in the smart ED is limited to 3.3kW/h. Since Watt=Votls*Amps, at 110, the max draw would be 30A. The max draw for 220 would be 15A.
Actually, it's the other way around: The charger is rated 16A, 100 - 240V. It will draw whatever current the EVSE pilot signal allows, but only up to 16A, independent of the supply voltage.

With the v2 Charge-amps cable it can draw 16A at 120V, that's a tad faster than with the stock brick that only allows 12A at the "high" setting. Just make sure you plug the other end into a 20A circuit.
 

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Actually, it's the other way around: The charger is rated 16A, 100 - 240V. It will draw whatever current the EVSE pilot signal allows, but only up to 16A, independent of the supply voltage.
Yes, I get that. We were not talking about the limit by advertisement. The original poster was claiming the max draw for the smart ED is 16A, which is factually incorrect. The max draw at 220V is 16A (really, 15A, but meh). At 110V the charger could draw up to 30A, if a 110V EVSE advertises that rating, which many can. (Again, the Power Xpress I own can advertise up to ~60A at 110V, ~36A at 220V.)

The car won't draw more than the advertised rate of the EVSE. That's a given. But on 110V, the smart can pull 30A if it's advertised.

That's the one qualm I have with J1772 based EVSE: The protocol advertises Amperage not Wattage. If the user doesn't know the difference and are using 110/220 device, they could wind up either charging at half the rate they expect to, or blowing a circuit when the car pulls twice what it should. The protocol as it stands can advertise up to 90A, but most chargers don't go above 40A, as the wiring and switching relays required to do so get quite expensive above that range.
 

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Discussion Starter #9
The max draw at 220V is 16A (really, 15A, but meh).
It says 16A in the documentation for the charger in the car, and that's what my car draws when it's charging on 240A via a Clipper-Creek with 20A pilot, but you're right: meh.

But on 110V, the smart can pull 30A if it's advertised.
Have you measured that with your Power Xpress? The smart documentation says 16A, but it's not entirely clear if that is the max at 120V, or only applies at 240V. They also call it "3kW max", when that's clearly untrue. A high-current, low-voltage EVSE doesn't seem very practical, but it'd be interesting to know that is an option.

That's the one qualm I have with J1772 based EVSE: The protocol advertises Amperage not Wattage. If the user doesn't know the difference and are using 110/220 device, they could wind up either charging at half the rate they expect to, or blowing a circuit when the car pulls twice what it should. The protocol as it stands can advertise up to 90A, but most chargers don't go above 40A, as the wiring and switching relays required to do so get quite expensive above that range.
I agree lots of people don't understand the difference or what any of it means. A lot more user education might be helpful. But many of the EVSE manufacturers websites make silly statements like "charge 10x faster with this!" that are at best misleading and at worst just lies.

But in the worst case it makes the charge take longer than the uneducated user expected. Don't see how you can blow a fuse if the EVSE is installed correctly and the pilot current signal matches the wiring / fusing of the supply to the EVSE.
 

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They also call it "3kW max", when that's clearly untrue.
I'm pretty convinced the people writing the documentation were not talking to the people making the cars. The whole "charges 80% in the first half of it's charge time", which we know is a lie, is just one prime example.

My understanding is that the charger is 3.3kW, which means it's top draw would be 3.3kW/h plus whatever it can pull while running (the largest item being the heater, in C&D). My bet is that's actually still under 3.5kW/h.

I plan on trying it on a 40A 120v line I have in my summer place in Corning in the spring (if it decides to ever show up). While I don't have way to directly measure the draw, I'll be able to tell based on charge speed if it's staying under 16A, going 30A, or doing something in between.

Don't see how you can blow a fuse if the EVSE is installed correctly and the pilot current signal matches the wiring / fusing of the supply to the EVSE.
For a permanent installed EVSE, yes. But that's not what the OP was talking about. This thread is specifically about a portable charger, which you can change the setting on rather easily, designed to be plugged into a wall outlet.
 
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