Revision 2 upgrade for Nissan EVSE - Allows full level 2!

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
GeekEV said:
That sounds great, Phil! Though I'm a bit confused by the statement that the LEAF draws 16a. It's a 3.3Kw changer in the car, right? By my math, that's 13.75A max at 240v. What am I missing?

But in any case, this rev 2 mod will be capable of up to 20A (if the car supports it)? Did I read that right?

Thanks!
Click to expand...

No, Nissan tells us the charger output is 3.3kW. Assuming a 240v circuit, The input is 16a x 240v or 3.84kva. kva is equal to kW only when there is unity power factor (1). Since the LEAF's on-board charger is power-factor corrected, it's probably close enough to call it unity for rough calculations.

The LEAF's on-board charger is a power conversion device, and in accordance with physics and the laws of thermodynamics, it is nowhere near 100% efficient.

As for the 20A capability, I will not know if I can allow it yet, as I mentioned more testing is required. But the prototype allows it.

-Phil
 
Ingineer said:
Nissan tells us the charger output is 3.3kW. Assuming a 240v circuit, The input is 16a x 240v or 3.84kva. kva is equal to kW only when there is unity power factor (1). Since the LEAF's on-board charger is power-factor corrected, it's probably close enough to call it unity for rough calculations.
Click to expand...
Got it. I thought, mistakenly, it was a 3.3kW draw, not output... That makes sense.

Just for academic purposes, based on what you said about the 33.3% duty cycle and 20a, that WOULD apply if using it with something other than a LEAF that supported higher current?

Thanks!
 
GeekEV said:
Got it. I thought, mistakenly, it was a 3.3kW draw, not output... That makes sense.

Just for academic purposes, based on what you said about the 33.3% duty cycle and 20a, that WOULD apply if using it with something other than a LEAF that supported higher current?

Thanks!
Click to expand...

Correct. There is no EV currently on the market right now I'm aware of, except for a Tesla with a converter dongle, that can draw more then 16A from J1772.

-Phil
 
QueenBee said:
I understand KISS well but I think anyone who plans on using this along with a quick220 would certainly need the 12A/220 model or as Phil noted at 16A draw a 15amp breaker will trip so if you didn't have two 20amp circuits you would be stuck at 12 amp 110volt draw.
Click to expand...

I'd have to agree with this statement. Of the few garages I have scouted for use of the Quick 220 none of them had two dedicated 20 amp outlets. At best I encountered one 20 amp and one 15 amp outlet. So in this scenario the Rev 2 would be popping breakers all the time.

While I want the full 16 amps to use at RV parks and with dryer plugs, I'd hate to vibe up the flexibility the Quick220 offers.

I vote for user selectable amperage settings. Then it becomes a full featured, "give me all you've got" EVSE!
 
nader said:
Of the few garages I have scouted for use of the Quick 220 none of them had two dedicated 20 amp outlets. At best I encountered one 20 amp and one 15 amp outlet. So in this scenario the Rev 2 would be popping breakers all the time.

While I want the full 16 amps to use at RV parks and with dryer plugs, I'd hate to vibe up the flexibility the Quick220 offers.

I vote for user selectable amperage settings. Then it becomes a full featured, "give me all you've got" EVSE!
Click to expand...

The question is, If I have to spend more dev time adding the user interface (as simple as it may be), how much extra are you willing to pay for selectable amperages?

-Phil
 
Ingineer said:
IBELEAF said:
I am probably way ahead of time, but still curious if this upgrade will work with future Leafs that might have 6.6 kWh chargers
Click to expand...
In the prototype, I have set the Pilot to 33.3% duty cycle, which will allow up to 20a. So if you had an EV with a 6.6kva charger, you would only get 4.8kva. That's about ~73%, so not bad.

I can't safely increase beyond 20a without new hardware in the EVSE. And as it is, I need to run extensive tests at 20a to verify there is no problem.

6.6kva will require 27.5a, which really should have better than 12awg cable as well, so really the whole EVSE would need to be replaced. (Except for the sticker on the front that says "Zero Emission"! =)
Click to expand...
So the Pilot is set to 33.3% duty cycle in all cases? So that's telling the vehicle that 20A is available at 120V and 240V?
On the LEAF, you point out the car will limit to 12A even if offered more by the EVSE, so it's a non issue for the current LEAF. Future LEAFs or other EVs might take the full 20A at 120V being offered by the EVSE, tripping 15A circuits.

I'm thinking that using a Quick220 or similar, that you will on occasion, be plugging in to 15A circuits and 16A would trip the breaker.

I also think about situations where the circuit is shared with a coke machine or some other modest loads or maybe other hotel rooms if you decide to Quick220 (with permission of course!) at a bed and breakfast etc.

So ultimately, you have three settings (based on the LEAF EVSE)

Auto (Always offers 20A, cars that accept more than 12A at 120V can be problemeatic)
8A (shared circuit 120V or 240V)
12A (dedicated 15A circuit 120V or 240V)
16A (dedicated 20A circuit 120V or 240V)
20A (dedicated 30A circuit 240V)

Or the Auto mode could be more sophisticated: (12A at 120V, 20A at 240V).

Value of selectable current option: +$200 as an easy figure. I'd pay more though, but given LEAF owner market and the effort, that seems a good price point. $100 would include more people, though the value is to people who need that sophistication. User selectable current is too complicated a feature for people who are blissfully ignorant of Amps and circuit breakers and want to sty that way.

To speed development, for the moment, you could offer the full level 2 mod for the LEAF, and people who need lower current (12A) or need both low (12A) and high current (16A) at 240V could just get two mod units and use the unit that suits the need. So they have to purchase two units, but they have hte flexibility of current level by using one or the other of the two units they've purchased. Long term a fancy, user adjustable current draw with an Auto mode for default would address more situations, but that can come later, maybe after the Phil Inc. public offering!

Purchasing two units is an additional cost outlay, but is partially offset by the additional cost a selectable current model would add, the development time, including finding a reliable moisture proof switch mechanism, units available sooner, redundancy of having two units for convenience adn backup etc.

You can put a catchy label on them: "Phil's 12A go anywhere EVSE", "Phil's 16A enhanced EVSE dongle". Ok, I leave that one to your marketing department! A large easy to read 12A or 16A on the units would make them easy to identify annd simple to use.
 
Ingineer said:
I'd love to hear what everyone thinks.

-Phil
Click to expand...

I'm thinking I wish I learned about this yesterday when my EVSE was still in your hands! ;) I'm not sure I'll want to bother with sending it back, but maybe...

Thanks for pushing the design along!

Bill
 
Ingineer said:
6.6kva will require 27.5a, which really should have better than 12awg cable as well, so really the whole EVSE would need to be replaced. (Except for the sticker on the front that says "Zero Emission"! =)
Click to expand...
The 6.6 kW chargers may be rated for charging power, so the input power would be higher. I consider the Level 2 to be a 30 or 32A supply at 240V, in any case, as you point out, it would require replacing most of the Nissan EVSE components for currents over 20A.

In the initial [J1772] standard, two charging levels are defined.
Code: 
Level        Voltage  Peak current 
AC Level 1   120 V    16 A 
AC Level 2   240 V    32 A (2001) 80 A (2009)
http://en.wikipedia.org/wiki/SAE_J1772
 
To save on development costs, I think it would be best to keep it simple. If someone want's 12A then purchase the upgrade Rev1. If someone want's to charge at higher current then purchase Rev2.

In the prototype, I have set the Pilot to 33.3% duty cycle, which will allow up to 20a. So if you had an EV with a 6.6kva charger, you would only get 4.8kva. That's about ~73%, so not bad.
Click to expand...

Wouldn't it be safer to set the pilot to allow up to 16A Max. Currently the Leaf can only draw 16A but when the next generation of Leaf comes with the 6.6kWh charger, trying to pull 20A from a 20A plug is bound to cause a few tripped breakers.
 
For those talking about using this with a Quick220 type device, I have a question. This is probably my electrical naïveté taking here, but wouldn't the 20A (maximum) draw be effectively split between the two 120v legs such that each circuit would effectively see 10A? That would be fine on a standard 15A circuit, no?
 
GeekEV said:
For those talking about using this with a Quick220 type device, I have a question. This is probably my electrical naïveté taking here, but wouldn't the 20A (maximum) draw be effectively split between the two 120v legs such that each circuit would effectively see 10A? That would be fine on a standard 15A circuit, no?
Click to expand...
No. you draw the full amount from both circuits. That's why 240v 12a charges your car twice as fast as 120v 12a.
 
Dave is correct.

You can always remember this rule: The current (amperage) is always the same in all parts of a circuit, If the car is drawing 16a, then everywhere you will see 16a flow throughout the circuit. Normally the circuit (imaginary) starts at the hot on 120v and returns to the neutral, the only difference on 240v is that the return is through the other hot leg.

This is why the upgraded EVSE can charge twice as fast on 240v without any increase in current. The EVSE doesn't see any additional current or voltage drop, so it's the same as on 120v.

-Phil
 
Ingineer said:
nader said:
Of the few garages I have scouted for use of the Quick 220 none of them had two dedicated 20 amp outlets. At best I encountered one 20 amp and one 15 amp outlet. So in this scenario the Rev 2 would be popping breakers all the time.

While I want the full 16 amps to use at RV parks and with dryer plugs, I'd hate to vibe up the flexibility the Quick220 offers.

I vote for user selectable amperage settings. Then it becomes a full featured, "give me all you've got" EVSE!
Click to expand...

The question is, If I have to spend more dev time adding the user interface (as simple as it may be), how much extra are you willing to pay for selectable amperages?

-Phil
Click to expand...

Give us a price estimate. (I won't hold you to it ;) ) $50, $100, more?

It also depends how much the firmware upgrade for Rev 2 costs too.
 
Ingineer said:
There is no EV currently on the market right now I'm aware of, except for a Tesla with a converter dongle, that can draw more then 16A from J1772.
-Phil
Click to expand...

FYI, there are some of us with old Ford RangerEVs with adapter cables that can connect the J1772-1996 (Avcon) to J1772-2009. So I can unplug my 3.3kW Leaf from the home Blink and plug the Ranger in through the adapter and pull 6.6kW just fine. (The Blink is connected to a 40amp breaker.) I have no idea what would happen if I tried to charge the Ford RangerEV through one of your modified adapters. I don't know about the flexibility of the charger built into the Ranger. For all I know, if it doesn't get a 6.6kW capable pilot signal it might refuse to charge.

So far I haven't encountered any J1772-1996 or J1772-2009 that aren't 6.6kW so I never tried it at lower rates.

If you ever build something that is 6.6kW capable and need someone to test it, let me know.

I guess I could try the 20A version of the Leaf adapter too if you wanted to see what happens.

A Tesla Roadster would be a more flexible test through, since you can pick the charge rate from the touchscreen in the vehicle.
(The Ford RangerEV doesn't offer any charge rate selection, so it is a mystery to me if it will work at less than ~30A. )


Oh, also I have a couple of old SCI EVSEs with Avcon/J1772-1996 output, and NEMA14-50 input.
They are on the large size to be considered portable.
 
From the forgotten 36: I'd love what ElectricVehicle said. I've always wondered why the volt has a low power setting. Good for the "share with the coke machine" situation, but that charge rate is so slow as to be sortof pointless
 
This is the best news I've heard yet! :D My only concern is that by the time I get my LEAF you may not be doing this anymore! :(

Do you think you'll still be doing the upgrades this fall/winter? :?:
 
Ingineer said:
The question is, If I have to spend more dev time adding the user interface (as simple as it may be), how much extra are you willing to pay for selectable amperages?
Click to expand...
For me, it's not the money as much as it is the user interface. When you first mentioned the possibility way back in the stone ages, you were talking about clicking the switch on the handle and toggling LEDs. I'd be worried about my wife, for instance, popping breakers or mistakenly charging at the wrong rate because she happened to stutter on the button, or do an extra plug in, in that scenario. Having it only work in 240v mode does alleviate that concern a bunch, though. I'd prefer a real 2 position switch myself, preferably one stiff enough that it can't be accidentally toggled. That makes the software easy, but the hardware more difficult...aren't us software guys always doing that? ;)

Anyway, to answer your question, I'd probably be willing to go for an extra $30-50 or so. In the end, we're only talking about a modest increase in charging time. I think a lot of the excitement here is more psychological than real...making the lowly "emergency" EVSE work exactly like the expensive units. In truth, the mod as it is is highly functional, and maybe entirely adequate.
 
TEG said:
FYI, there are some of us with old Ford RangerEVs with adapter cables that can connect the J1772-1996 (Avcon) to J1772-2009. So I can unplug my 3.3kW Leaf from the home Blink and plug the Ranger in through the adapter and pull 6.6kW just fine. (The Blink is connected to a 40amp breaker.) I have no idea what would happen if I tried to charge the Ford RangerEV through one of your modified adapters. I don't know about the flexibility of the charger built into the Ranger. For all I know, if it doesn't get a 6.6kW capable pilot signal it might refuse to charge.

So far I haven't encountered any J1772-1996 or J1772-2009 that aren't 6.6kW so I never tried it at lower rates.

If you ever build something that is 6.6kW capable and need someone to test it, let me know.

I guess I could try the 20A version of the Leaf adapter too if you wanted to see what happens.

A Tesla Roadster would be a more flexible test through, since you can pick the charge rate from the touchscreen in the vehicle.
(The Ford RangerEV doesn't offer any charge rate selection, so it is a mystery to me if it will work at less than ~30A. )


Oh, also I have a couple of old SCI EVSEs with Avcon/J1772-1996 output, and NEMA14-50 input.
They are on the large size to be considered portable.
Click to expand...

If the Ranger is J1772 compliant with old Avcon standard, as it should be, it will charge at the lower rate. The standard originally was developed with a simple PWM system so current adjustment can be done with a simple analog circuit, so I'd be surprised if it didn't work properly.

-Phil
 
davewill said:
For me, it's not the money as much as it is the user interface. When you first mentioned the possibility way back in the stone ages, you were talking about clicking the switch on the handle and toggling LEDs. I'd be worried about my wife, for instance, popping breakers or mistakenly charging at the wrong rate because she happened to stutter on the button, or do an extra plug in, in that scenario. Having it only work in 240v mode does alleviate that concern a bunch, though. I'd prefer a real 2 position switch myself, preferably one stiff enough that it can't be accidentally toggled. That makes the software easy, but the hardware more difficult...aren't us software guys always doing that? ;)

Anyway, to answer your question, I'd probably be willing to go for an extra $30-50 or so. In the end, we're only talking about a modest increase in charging time. I think a lot of the excitement here is more psychological than real...making the lowly "emergency" EVSE work exactly like the expensive units. In truth, the mod as it is is highly functional, and maybe entirely adequate.
Click to expand...

I doubt seriously I will consider any kind of user-interface that involves drilling a hole in the housing. The best I could do is a magnetically operated switch, such that you wave a magnet at the front, and it changes modes. The LEDs would then indicate what mode the unit is in.

The best method which would be the lowest cost, is simply to have several modes that can be programmed by plugging/unplugging the J1772 connector in a certain sequence. The mode would be remembered between power cycles, and it's unlikely someone would accidentally "trip" this mode selection.

Another "no hardware" option is to use a paperclip between the 2 small holes in the J1772, which would cycle the mode. (this would not be dangerous, as there is no voltage over 12 present)

-Phil
 
Ingineer said:
I doubt seriously I will consider any kind of user-interface that involves drilling a hole in the housing. The best I could do is a magnetically operated switch, such that you wave a magnet at the front, and it changes modes. The LEDs would then indicate what mode the unit is in.

The best method which would be the lowest cost, is simply to have several modes that can be programmed by plugging/unplugging the J1772 connector in a certain sequence. The mode would be remembered between power cycles, and it's unlikely someone would accidentally "trip" this mode selection.

Another "no hardware" option is to use a paperclip between the 2 small holes in the J1772, which would cycle the mode. (this would not be dangerous, as there is no voltage over 12 present)
Click to expand...
Wouldn't the plug/unplug sequence idea open up the possibility of having only a 15amp circuit available, but the device in 16amp mode with no way to change it but plugging it into the car and blowing the breaker? I guess you'd have to assume a 120v socket is always available in those cases. I like both the magnet and paperclip ideas, myself, and can see that the paperclip one is much simpler to execute. I can see where some people might be squeamish about poking around the J1772 with a paperclip, but we're enthusiasts, aren't we!
 

Similar threads

L
Has any one try this Grizzl-E Level 2 240V / 40A Electric Vehicle (EV) Charger ?
2 3
Replies
47
Views
2K
Jim66
J
C
A thread for people happy with their Leaf
2 3 4
Replies
79
Views
5K
denwood
D
majbthrd
quantified: how much power is used to charge an EV
Replies
6
Views
863
Bombastinator2
B
D
Whacky Hacky: Adding extra DC/DC and DC/AC converters to PDU? (Gen1 Leaf)
2 3
Replies
42
Views
2K
Jsprinkle
J
J
Anbull 120v/240v 16a max, inexpensive adjustable Chinese EVSE
Replies
11
Views
6K
SageBrush
S

Latest posts

Back
Top