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Re: Q: 120V emergency cord

Posted: Thu Jun 24, 2010 10:46 am
by evnow
LTLFTcomposite wrote:The possibilities for shoddy half-assed electrical setups are pretty much unlimited. I've got a fair amount of experience doing electrical work though and feel there's a lot to be said for having properly engineered, certified equipment installed as it was intended. That said, you know there are going to be a lot of EV's charged by hot-wiring porch lights. It's all fun and games till somebody loses an eyeball.
You mean something like this is not upto code ?

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Re: Q: 120V emergency cord

Posted: Thu Jun 24, 2010 2:45 pm
by planet4ever
LEAFer wrote:At Level2 charging you need the pilot signal, not just the "juice". I could be wrong ... may be the LEAF can be fooled to think it is doing Level 1 charging (where no pilot signal is needed) but use the 240volts you supply anyway.
I don't think your level 1 pilot statement can be right. Level 1 goes through the same connector on the Leaf as level 2, and I am quite sure that level 1 charging uses exactly the same kind of handshaking as level 2; it is just that the car and the EVSE agree on a different voltage and amperage. Yes, I said EVSE. The 120V "emergency cord" is not just a cord. It has an EVSE built into it where it plugs into the wall.

Re: Q: 120V emergency cord

Posted: Thu Jun 24, 2010 4:26 pm
by garygid
The EVSE "handshaking" (the Control Pilot wire) probably carries a different "DC" voltage to the car (maybe just one different resistor in the EVSE) to indicate 120v power instead of 240v power.

With "no" pilot signal (or perhaps some minimal, fixed-voltage pilot signal) from the EVSE, I think the car is to expect 120v and draw no more than 12 amps after the J-Plug is in place.

Someone with the J1772 specs (AndyH) might be able to tell us for sure.

I would look if I had the standards document.

Re: Q: 120V emergency cord

Posted: Thu Jun 24, 2010 6:24 pm
by LEAFer
planet4ever wrote:
LEAFer wrote:At Level2 charging you need the pilot signal, not just the "juice". I could be wrong ... may be the LEAF can be fooled to think it is doing Level 1 charging (where no pilot signal is needed) but use the 240volts you supply anyway.
I don't think your level 1 pilot statement can be right. Level 1 goes through the same connector on the Leaf as level 2, and I am quite sure that level 1 charging uses exactly the same kind of handshaking as level 2; it is just that the car and the EVSE agree on a different voltage and amperage. Yes, I said EVSE. The 120V "emergency cord" is not just a cord. It has an EVSE built into it where it plugs into the wall.
I am basing my statement on what I have learned about Tesla's implementation. The "emergency cord" supplied with a Roadster is simply a cable with NEMA 5-15P GFCI on one end, and the Tesla proprietary charge port connector (instead of J1772 plug) on the other end. On "teslamotorsclub.com" there is talk about the GFCI being too sensitive, causing tripping (and resultant abort of the charging process), and it has been suggested, and some owners have done so, to replace the GFCI NEMA5-15P with a regular non-GFCI version. There simply can't be any other "intelligence" (control signal) in that connector. Yes, that's unconfirmed, but a pretty reasonable bet (if I were a betting man). Here's a link to Tesla's product: http://shop.teslamotors.com/collections ... nector-120

And here's the TMC topic for your reading pleasure: http://www.teslamotorsclub.com/showthread.php?t=2875

Edit: This forum is about the LEAF ... the technique used could naturally be different ... so ... we would like to know: Is the "emergency cord" a "real" EVSE, or just a "dumb" 120V/12A "extension cord" ?

Re: Q: 120V emergency cord

Posted: Thu Jun 24, 2010 6:56 pm
by garygid
With a 120v extension cord, a J-Plug (the J1772 plug), a "handle"/hood for the J-Plug, and possibly a few small parts, it should be possible to make an "emergency" 120v LEAF-charge "hose".

Of course, it might not be legal to use it, and a "real" 120v EVSE comes with each LEAF. So why bother to make one, unless the Nissan "hose" is too expensive.

Getting the J-Plug and the "handle" is the hard part.
If I can obtain these, I will see exactly what needs to be done from the J1772 specifications.

PM for my address if you want to send a J-Plug, a "handle", or a copy of the J1772 specs.

Re: Q: 120V emergency cord

Posted: Thu Jun 24, 2010 7:22 pm
by EVDRIVER
evnow wrote:
LTLFTcomposite wrote:The possibilities for shoddy half-assed electrical setups are pretty much unlimited. I've got a fair amount of experience doing electrical work though and feel there's a lot to be said for having properly engineered, certified equipment installed as it was intended. That said, you know there are going to be a lot of EV's charged by hot-wiring porch lights. It's all fun and games till somebody loses an eyeball.
You mean something like this is not upto code ?

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Did you Google Earth my address?

Re: Q: 120V emergency cord

Posted: Thu Jun 24, 2010 8:09 pm
by evnow
EVDRIVER wrote:Did you Google Earth my address?
This is the place I stayed at when visiting India :lol:

In some places in the sub-continent it is common to "steal" power by directly connecting to live wires that run overhead everywhere. They just bribe the utility guy.

Things can get so bad - the "trasmission losses" can run over 50%.

http://news.bbc.co.uk/2/hi/business/4802248.stm
Similar scenes can be seen in many parts of Delhi. According to the latest official estimate, as much as 42% of the power supplied to India's capital disappears through "transmission losses", meaning it is consumed without being paid for. In effect, it is stolen.

Re: Q: 120V emergency cord

Posted: Thu Jun 24, 2010 10:00 pm
by garygid
In the USA, was it only 30% electrical power transmission losses nationwide?
Somebody had a chart of energy sources and uses.

Re: Q: 120V emergency cord

Posted: Fri Jun 25, 2010 6:17 am
by IceRaven
I have seen converters that convert 120v to 220v (its a black box you plug in a 120v outlet and theres a 220v outlet on it), I guess thats equally useless in this case?

What is the "Pilot Signal" ?


I guess if its technically possible to have a cable that connects to a 120v and charges faster but there arent any initially, when thousands upon thousands of leafs are in the market, if Nissan doesnt offer such a product someone else might, I hope it wouldn't be 600$ like the Tesla cable though.

I'll have to check ranges, but theres a cottage I go over to once every few years, I think I can get there but would have a low charge on the battery and there wont be an official 220v Station at the cottage or any fast charge nearby(forest and cottages), being able to recharge with 120v overnight in about 12h would do the trick and would be great. Otherwise I'll just rent a car for these rare trips (but theres a so close feeling)

Re: Q: 120V emergency cord

Posted: Fri Jun 25, 2010 6:24 am
by mwalsh
IceRaven wrote:I have seen converters that convert 120v to 220v (its a black box you plug in a 120v outlet and theres a 220v outlet on it), I guess thats equally useless in this case?
Step-up transformer. I have one I use to drive an old stereo system I brought with me from the UK. Can't imagine they'd be applicable to the Leaf in any way.