Inside the NA spec L1 EVSE

[planet4ever]

Clothes dryers could technically be considered portable perhaps? Unfortunately the NEC has a section specifically for EVSEs but not dryers. Contrast to something like an electric stove, which must be hardwired. I think the real distinction is the design and certification of the appliance.

LOL - never considered a clothes dryer to be portable, but then I'm not the NEC either.
My electric stove has a plug. I don't think stoves are required to be hardwired either.

Yes, both our electric dryer and our electric range plug in to 240v outlets, but in both cases they will probably be unplugged once in their lifetime. I just had an experience a couple of days ago with a desk-top computer that suddenly shut down while I was using it. Looking for a reason, I noticed a slight sizzling sound and tiny flashes of light where the power cord plugged into a power strip. The truth is that simple blade-type plug/jack connectors are not a very reliable means to transmit electricity, and they become much less reliable if cheap components are used or the plugs are inserted and removed repeatedly.

This may be the primary reason for Nisson's insistance that the supplied L1 EVSE is for emergency use. Personally, I plan to go in the opposite direction, and leave it semi-permanently attached to the wall plug. I'm hoping eventually to be able to pick up a second one for a reasonable price (say $200) so that I can have an emergency backup that I carry in the car.

(But then, that topic of course has been beaten to a pulp already.)

True, but we've got to have something to talk about while we're waiting, right?

Ray

 

[smkettner]

Contrast to something like an electric stove, which must be hardwired. I think the real distinction is the design and certification of the appliance.

I have a stove from the 60s that plugs into a 240v outlet.

 

[smkettner]

We have discussed this is detail before. A NEMA 6-20 plug will not last and the outlets at public stations would fall apart regularly, this is not an RV with low cycling. In addition, you need a pilot signal for the various current loads in public charging locations, you can't do that with a NEMA plug. The EVSE is needed for those that charge in public areas.

What if there was no pilot signal? 20a plug & 20a outlet..... what information would there be to exchange?
I see no evidence a 6-20 or 6-50 could not be used ten times a day for many years.
Besides even the legacy evse stations have not survived well. If the initial cost was 1/10th it would seem the $20 connector could be replaced annually at a lower cost than maintaining the old paddles or the J connector.
I realize that the J connector is just about control, billing and tracking usage.

And I realize the ship has sailed. Still my opinion will be perpetually unchanged.

 

[garygid]

The Control Pilot only says "I am here and ready to go" and "draw a maximum of NN amps" from the EVSE to the car, and "Plugged into a (J1772-standard) EV", "I require ventilation (or not)", and "Switch Power ON (or OFF)" from the car to the EVSE.

No voltage level (J1772 should be from about 100v to 250v AC), or car ID information.

 

[planet4ever]

I have long thought the Leaf (and other EVs) should have just had a cord with NEMA 6-20p on the end.

I may be misinterpreting you, but it sounds as if you are saying there should be a (presumably retractable) cord permanently connected to the car with a 6-20 plug on it. That would mean that you could only charge at 240v 16A. No 120v charging for you, unless you used a really scary sounding 120/240 adapter. (I hope nobody makes anything like that.) If you put a faster charger in the car, you would have to change the cord, and once you did, you could no longer use 6-20r outlets. Not even with an adapter, since the car wouldn't know to limit itself to 16A.

No, I don't much like this idea.

Ray

 

[EVDRIVER]

We have discussed this is detail before. A NEMA 6-20 plug will not last and the outlets at public stations would fall apart regularly, this is not an RV with low cycling. In addition, you need a pilot signal for the various current loads in public charging locations, you can't do that with a NEMA plug. The EVSE is needed for those that charge in public areas.

What if there was no pilot signal? 20a plug & 20a outlet..... what information would there be to exchange?
I see no evidence a 6-20 or 6-50 could not be used ten times a day for many years.
Besides even the legacy evse stations have not survived well. If the initial cost was 1/10th it would seem the $20 connector could be replaced annually at a lower cost than maintaining the old paddles or the J connector.
I realize that the J connector is just about control, billing and tracking usage.

And I realize the ship has sailed. Still my opinion will be perpetually unchanged.

The plugs you mention do not last and are not designed for repetitive automotive use, it's that simple.The connection at the plug, strain relief, wire bindings, etc, they are not designed for repetitive use, even with my personal use I have replaced several and the outlets are far worse. One thing you continue to dismiss it that many types of vehicles will charge at any given location. If the location can only support a given amperage and a car with a higher load charger is used it will trip the breaker rather than reduce the load per the pilot signal. You are assuming every car has the same load level. ALso , repeated use of "hot" loads creates wear on the outlet. There are multiple valid reasons for a pilot signal and a standardized plug, the implementation you suggest was never designed for the application. The high cost of some EVSE units is a separate issue, not related to the actual utility and benefits but more to price gouging. The ship that sailed is a good one, how some build and price that ship is subject to much debate.

 

[LTLFTcomposite]

What about cheating by moving one of the transformer input leads to ground? The red and black wire pass through that donut that is presumably the coil to detect ground fault. Need to tap ahead of that. And of course it wouldn't work if the outlet you were plugging into is GFCI protected.

 

[mwalsh]

Since everything but the disassembly is well above my pay grade, I'm going to be sending my unit off to a knowledgeable EV enthusiast today for closer inspection and possible reverse engineering.

I personally think the idea of replacing the circuity inside for a completely new board is quite possibly the way to go. That way you could keep the original components and revert the box back to stock if necessary.

 

[wwhitney]

What about cheating by moving one of the transformer input leads to ground?

That would be a poor idea from a safety point of view. But perhaps you could feed the modified EVSE with a 240/120V 4-wire plug?

Cheers, Wayne

 

[LTLFTcomposite]

What about cheating by moving one of the transformer input leads to ground?

That would be a poor idea from a safety point of view. But perhaps you could feed the modified EVSE with a 240/120V 4-wire plug?

Cheers, Wayne

I thought about that as well... an L14 connector perhaps, or a 4-wire dryer plug.

Didn't dryers and ranges put small 110v loads against ground for years? Not saying it's ideal, but also not clear it's really that big an issue.

 

[Smidge204]

Just had a thought about the potting - if you're willing to risk it, make friends with a radiologist and get the PCB x-rayed. :lol: It's been done before and works pretty good.

The transformer likely provides 20V for pilot signal as well as relay switching. That looks like a voltage regulator with the heat sink there. I see what is probably two diodes neat where the 20V power hooks up - that tells me they either use a half-wave rectifier or they use a center-tapped transformer - but I don't see a third wire anywhere to make that work.

A few caps and chokes for power conditioning and what looks like a simple ground-fault detection toroid (pink wire). Really isn't much to it at all and it should be a relatively simple task to cobble one up for anyone versed in hobbytronics and $30 to waste (J1772 plug not included!)

The idea that anything made in China is RoHS compliant is somewhat amusing though!
=Smidge=

 

[ERG4ALL]

This is a little off topic, but relevant. I plan on displaying our LEAF at some environmental fairs in some of the less populated areas of the state. We would be driving the LEAF from our mountain home about 32 miles (some speeds as high as 65 mph) to the event in the morning and back perhaps even after sundown. What I want to do is to purchase a 2000W 120V inverter type generator and plug the car in while it is on display. This way I could have the doors open and show some of the electronics to interested persons. I've chatted with Nissan and they make no commitment whether that is okay or not. I'm wondering if anyone out there has tried trickle charging from a generator yet using the L1 charging plugs talked about here.

 

[smkettner]

This is a little off topic, but relevant. I plan on displaying our LEAF at some environmental fairs in some of the less populated areas of the state. We would be driving the LEAF from our mountain home about 32 miles (some speeds as high as 65 mph) to the event in the morning and back perhaps even after sundown. What I want to do is to purchase a 2000W 120V inverter type generator and plug the car in while it is on display. This way I could have the doors open and show some of the electronics to interested persons. I've chatted with Nissan and they make no commitment whether that is okay or not. I'm wondering if anyone out there has tried trickle charging from a generator yet using the L1 charging plugs talked about here.

I have not read an actual generator test yet. Although I think a Honda 2000 would be right on the edge with 1600VA continuous rating. I plan to try my Kipor inverter generator 2300va rated, 2600va surge when I get my Leaf. But that could easily be May or later. I think someone checked the power factor with a Kill-a-Wall meter and it was 95% or better so you may not need too much additional apparent power. Even testing at a Honda dealer may not prove it out unless they will let you test for over 30 minutes. Consider a Yamaha EF2400is for a little more power than the "2000" models and still have low noise.

A new thread might well be appropiate.

 

[ERG4ALL]

Thanks for the response. I looked up the Yamaha EF2400iSHC and it weighs 75 lbs dry. Anybody found something similar that doesn't weight that much? Either that or I need to come up with some leverage device to get it out of the package well in the LEAF.

 

[LTLFTcomposite]

How about the Honda EU3000i they recently introduced? (no firsthand experience)

 

[garygid]

Replacing the 3-wire pigtail with a 4-wire pigtail and using plugs and sockets with properly-connected Neutral and Ground would most likely work fine as far as "feeding" the transformer.

It is not yet clear if changing the present white "Neutral" wire to a red "Hot#2" (to try and make a 240v/120v EVSE) might have some other adverse impact on the circuit board. If the present Neutral just runs through the board (without connecting to ANY components other than the transformer input) to the Relay module, and then out to the EV, the chances of success are good.

Then, the transformer would remain wired to Hot and get rewired to the new Neutral, for 120v transformer operation always.

The "new" Power wire is then wired, in the pigtail plug, to the "other" Hot for 240v operation, or to Neutral for 120v operation.

Presently, if the 120v socket is wired incorrectly (Hot and Neutral swapped, fairly rare in modern, professional work), the EVSE still works. In the new configuration, the transformer would not get power, so the EVSE would appear "dead".

Wiring the transformer between Hot and Ground is not recommended for safety reasons.

Finding a way to "switch" from 12-amp "Max-Current" to 16-amps would make the modified EVSE even more versatile, but is not really necessary, since charging is not all that much faster (only about 25% increase, because the LEAF apparently does not use the full 16 amps, and there is/can be almost 2 hours of "EQ" time when near 100% SOC).

The 240v mod alone, once VERIFIED as SAFE, would be relatively easy to do, and cuts the charging time approximately in half, roughly 20 hours to roughly 10 hours, a big, useful change.

NOTE that it would be technically illegal (NEC 625.13) to use it as a 240v EVSE for EV charging because it (apparently) does not have the required strain relief.

Successful raising of the Max-Current from 12 to 16 amps (switchable perhaps) might require changing the 15-amp fuse, and other component and wiring-rating checks. The benefit is less noticable, being less than a one-third gain. Also, CAREFUL use would be necessary to insure that the Max-Current setting was appropriate for the wall curcuit and breaker. The 12-amp setting could be used almost anywhere.

It seems that the J1772 connector itself is labeled for 20-amp operation.

The plug on the new pigtail could be a 4-pin 240v plug, perhaps a "waterproof" twist-lock type, with adapters made for the various intended-use sockets.

 

[DarkStar]

NOTE that it would be technically illegal (NEC 625.13) to use it as a 240v EVSE for EV charging because it (apparently) does not have the required strain relief.

We should probably use the term "non-conforming" since we don't mean illegal in the sense of "not legal".

 

[Coffee_Slurry]

I have access to an X-Ray machine if someone really is that curious about what's under the potting.

 

[garygid]

1. Looks like a "prominent" forum member will get a chance to get us better information on the EVSE's "guts".

2. Generator issues:
a. You want a well-formed "full" sine wave output, not a "Modified Sine Wave" output.
b. "Continuous" Power Rating of at least (120v x 12 amps) 1440 watts. Beware of "Peak" ratings.
c. Noise: Some are "spec'd" (rumored?) to be a LOT quieter, at least when run at their lower power points.
d. Vent exhaust fumes properly. Place generator down-wind if possible.
e. Extension cord safety. BEWARE, and take all appropriate precautions.
f. Run time per full tank. Often specs are at 50% power, so expect to fill more often.
g. Refilling a hot generator, use a funnel, and CAUTION.
h. After the EV is fully recharged, it might be best to turn the generator off, at least for a while.
i. Let the generator cool off, drain the gas, allow spilled gas to fully evaporate before transporting.
j. Make sure gasoline containers are good, very sturdy, fume-free. Technically illegal to transport inside the vehicle, I suspect. You do not want to become a human torch in a crash!
k. You do not want to be overcome by fumes. With any hint, roll down the windows, and fix the problem.
l. You could arrange for somebody with an open-bed pickup to transport the gas, and perhaps even the generator.

----------------
I just started a new Thread on the following subject:

CAUTION: somebody might "accidently" change the car from "ACC" to On/Ready, release the brake, put it in gear, and cause the car to "run away", possibly injuring people or objects. AT LEAST use some LARGE wheel-blocks on all four wheels.

If one puts the LEAF in ACC mode, then removes the RFID from the area, will the LEAF refuse to go into READY?

Yes, it would be nice if the software provided a password-protected "Display" mode, where the car could NOT be made to move. (Would be easy for Nissan to do.)

Does the LEAF require a seat belt, or passenger doors closed (or anything else on a fused circuit) before it will move?
If so, perhaps that sensor could be unplugged (or jumpered), or some fuse could be removed for display purposes?

 

[mwalsh]

Well my L1 is off to the Bay Area via UPS. I guess watch this space for updates on what they find!