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Re: We need a portable 240v EVSE

Posted: Sat May 01, 2010 11:45 pm
by garygid
16 hour fill-up vs 4 hour

To me, it is a big difference if trying to commute 80 miles at CA freeway "safe" speeds.

But, "easy" if I can charge 1/4 tank at lunch.

Re: We need a portable 240v EVSE

Posted: Sun May 02, 2010 3:52 am
by planet4ever
garygid wrote:16 hour fill-up vs 4 hour

To me, it is a big difference if trying to commute 80 miles at CA freeway "safe" speeds.

But, "easy" if I can charge 1/4 tank at lunch.
Well, if you're counting on a 4 hour fill-up, that's the 6.6kW charger.
a) It's my understanding that won't even be available in the Leaf until the 2012 model.
b) I believe 6.6kW is well beyond the current used by anything but a large industrial clothes dryer, and those are also hardwired.

So, obviously, you aren't running home for lunch. Where do you plan to find 240V to plug into? There are a lot of charging stations being installed in public places, and those will already have the J1772 connector, so no worry. If you're planning on talking your employer into running 220 out to your car, adding the hardwired connector would be a tiny increment on the cost. (All the scary stuff about $2200 includes wiring and installation.)

Re: We need a portable 240v EVSE

Posted: Sun May 02, 2010 4:33 am
by LTLFTcomposite
I assume all of you have seen these:

http://www.j1772connector.com/

http://www.arb.ca.gov/msprog/zevprog/st ... j1772.doc

http://www.teva2.com/J1772.html

Interesting comment in that last one:

Another article I read mentioned that if there were no signals, then the connector would only deliver 12 amps at 120 vac, making it a Level 1 connector which would satisfy lots of the existing chargers that we have.

As I interpret that, the car would assume it is only being fed 120 volts without the signaling telling it otherwise. It may have a safeguard to not close the relay if it detects higher voltage without the correct signaling. If you did zap it with 200 when it was only expecting 120 that could be bad.

Re: We need a portable 240v EVSE

Posted: Sun May 02, 2010 6:54 am
by EVDRIVER
mitch672 wrote:Because the J-1772 spec can supply up to 70Amps, that is the most likely reason the hardwiring is required. A portable level 2 charging cord/evse could be designed and built to run off a 30A dryer outlet, but someone would need to do it and get it UL approved. Probably no one wants to spend the money on it, as most see the 120v level 1 cord sufficient for portable use.
Portable 120 charging is useless unless you bring a sleeping bag. Every person I know with a n ev has a portable 240 cord and at least 5 adaptors. This will still be the case for those with friends in remote areas, if it were Europe one could use a standard outlet but the issue would likely be current restriction which is why the box is used to determine the supply capabilities in these cases. If you are nit versed in electricity and evs or have a questionable environment where you charge, get the box.

Re: We need a portable 240v EVSE

Posted: Sun May 02, 2010 12:24 pm
by garygid
The "standard" electric dryer home socket is usually wired to a 30-amp (are newer ones 40-amp?) breaker.

My pre-1980 home has a 30-amp dual breaker for the dryer, so I would probably need to limit the e-fuel rate to 24 amps (80% of 30, and not let the Leaf "suck" the full 30 amps) if I use that socket.

When the Leaf gets the 6.6 kW (wants 30 amps, could take up to 32 from a 40-amp breaker) charger, if the Level 2 EVSE indicates that only 25 are available, will the LEAF's internal charger "back off" to 25 amps, or "drop back" to 15 amps?

Re: We need a portable 240v EVSE

Posted: Sun Jun 20, 2010 8:06 am
by garygid
Apparently (might not be final), the EVSE from AV will have an internal setting (probably not a user-selectable setting) for "offering" the vehicle a maximum of 30 amps (requiring a 40-amp dual breaker). Really, it could "offer" 32 amps.

For installation on a 20-amp breaker, it is likely that it has a 15 (or 16) amp "setting" for its max-current indication. It is not clear if a 24-amp setting (for a 30-amp breaker) will be available, but I expect it will be.

A portable version of the EVSE would require this "max-available-current" setting to be user-selectable to match the capabilities of the circuit that the EVSE gets plugged into. Yes, that would generally require an "aware" user, but the sockets to be used frequently could be labeled to facilitate making the correct setting.

Also, frequently-used sockets could be equipped with a nearby switch (or shutoff) so that plugging and unplugging is very rarely done on a live circuit.

Or, a proper (European-style?) 240v safety plug and socket could be installed. With these "safety" sockets, by the time the plug is extracted from the socket far enough to be able to touch the contacts, the contacts are no longer "live" (they have disconnected from the "live" contacts inside the socket).

Re: We need a portable 240v EVSE

Posted: Sun Jun 20, 2010 8:23 am
by mwalsh
garygid wrote:Or, a proper (European-style?) 240v safety plug and socket could be installed. With these "safety" sockets, by the time the plug is extracted from the socket far enough to be able to touch the contacts, the contacts are no longer "live" (they have disconnected from the "live" contacts inside the socket).
The most common way of incorporating "safety" in a 240v socket in the UK these days is to have an on/off switch incorporated into it's wall plate. I don't remember if this was commonplace when I was a kid or not...I certainly don't remember having to turn sockets on, but then it's been a good few years too. I think you'd be hard pressed to find a UK socket not fitted thusly these days.

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I also think the UK is fairly uncommon in this respect, because I don't remember having to switch sockets on in other areas of Europe/Scandinavia where I've traveled.

Re: We need a portable 240v EVSE

Posted: Sun Jun 20, 2010 8:38 am
by garygid
Nice picture, thanks.

Do you have any idea what the max current rating of this type socket?

Is there something similar for higher-current loads, like electric driers, shop equipment, etc?

Re: We need a portable 240v EVSE

Posted: Sun Jun 20, 2010 8:40 am
by EVDRIVER
planet4ever wrote:
garygid wrote:16 hour fill-up vs 4 hour

To me, it is a big difference if trying to commute 80 miles at CA freeway "safe" speeds.

But, "easy" if I can charge 1/4 tank at lunch.
Well, if you're counting on a 4 hour fill-up, that's the 6.6kW charger.
a) It's my understanding that won't even be available in the Leaf until the 2012 model.
b) I believe 6.6kW is well beyond the current used by anything but a large industrial clothes dryer, and those are also hardwired.

So, obviously, you aren't running home for lunch. Where do you plan to find 240V to plug into? There are a lot of charging stations being installed in public places, and those will already have the J1772 connector, so no worry. If you're planning on talking your employer into running 220 out to your car, adding the hardwired connector would be a tiny increment on the cost. (All the scary stuff about $2200 includes wiring and installation.)

I have been charging at friends houses, costcos and parking lots, rv parks and dual pig-tail 120 outlets for three years at 7.2kw with no issue. At 240 that is only 30A which is supported by all old and new 240 charge stations. At 6.6kw that is only 27A. I have 5 basic adaptors I use and I can charge on anything except paddle chargers but who cares because where there is a paddle the is an AVCON and now there will be a "J"

Re: We need a portable 240v EVSE

Posted: Sun Jun 20, 2010 8:43 am
by mwalsh
garygid wrote:Do you have any idea what the max current rating of this type socket?
13 Amps. I think there is supposed to be a 15A version too, but that might be based on older BS standards. Currently looking on the web for details.

There is apparently a switched 32amp industrial socket too, but I don't know much about it:

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