2015 S not charging at 6.6kW

[Ninjarider1978]

Hi all,

A couple weeks ago i had a problem with my leaf charging system. The vehicle with the exclamation mark showed up on the dash and i was unable to charge with a few different chargers. That went away the same day and the vehicle has been fine ever since. I took the vehicle in today to nissan and they had a look and found nothing wrong. I had it in for another recall so i had them check out that fault as well.

When i first got the vehicle i quickly got an old android phone and obd2 adapter and closely studied all the vehicles parameters and i am sure the vehicle would charge at >6kW using my clipper creek HCS-40. Ever since that incident i have notices the charging doesnt like to be above 5.5kW and i have noticed this is happening at any level 2 charger. Is this a normal charge rate or should i be seeing 6.6 kW with my clipper creek? If there is an issue with the charger that i should be taking the car into nissan about or should i not worry?

 

[91040]

Where is the 5.5kW number coming from, LeafSpy?

1) 6.6kW is the max energy into the charger in the car but the amount into the battery will be less.
2) Are the EVSEs, you are using, on 208 or 240VAC?
3) Is the EVSE's output 30A? Blinks have been limited to 24A.

I would expect around 6kW on your Clipper Creek though, so there may be something going on.

Hi all,

A couple weeks ago i had a problem with my leaf charging system. The vehicle with the exclamation mark showed up on the dash and i was unable to charge with a few different chargers. That went away the same day and the vehicle has been fine ever since. I took the vehicle in today to nissan and they had a look and found nothing wrong. I had it in for another recall so i had them check out that fault as well.

When i first got the vehicle i quickly got an old android phone and obd2 adapter and closely studied all the vehicles parameters and i am sure the vehicle would charge at >6kW using my clipper creek HCS-40. Ever since that incident i have notices the charging doesnt like to be above 5.5kW and i have noticed this is happening at any level 2 charger. Is this a normal charge rate or should i be seeing 6.6 kW with my clipper creek? If there is an issue with the charger that i should be taking the car into nissan about or should i not worry?

 

[Ninjarider1978]

Yes, sorry. These charge numbers are using leaf spy and is the sum of the charge into the battery as well as any aux power being drawn by other devices. So it would be the total supplied by the EVSE.

As far as voltage goes, i havent measured at my house but i can assume it is 240VAC since i dont live in a condo or townhouse etc. Yesterday i charged at 2 other stations one was a chargepoint and the other was eaton. I didnt check using leafspy at the chargepoint but the app said it was around the 5.5 kW rate and the charging at the eaton i was in the car with the app open watching occassionally and i saw as a max 5.5 kW at any given time and that number fluctuated alot going as low as 5.0 kW at times. Which is another part that makes me curious is the fluctuating charge rates i saw. Regardless of what the charger can output, i would think the rate would be fairly constant, but i dont have enough experience to know for sure.

I kinda hope the charger has another fault so that i can take it in and maybe have it replaced or something.

My background is as electrician and electrical technologist, so i understand alot in terms of power consumption, voltage and current. I just dont know if what i am seeing is normal.

 

[knightmb]

It does sound like either the L2 is using less current or the onboard charger in the Leaf is not using full current available.

5.5 kW would be either 240 volts AC @ 24 amps max (a lot of L2 are limited to 24 amps) or the vehicle is limiting charge current to 24 amps. If the L2 was using the 3 phase 208 volt AC then charging power would be lower to around the sub 5kW range (4,992 watts). So either all the L2 stations around you just can't put out more than 24 amps or the charger in the Leaf is limiting charge power to 24 amps for some odd reason?

 

[Ninjarider1978]

I was under the impression the EVSE was basically just a glorified contactor that receives a signal from the car to close the contactor when requested. I didnt think it had the ability to regulate current flow, i thought it was the on board chargers responsibility to regulate current flow. The chargepoint charger i went to yesterday says its max output is 6.6kW according to the app. Thats just a value displayed on the specific charging station, not a real time value.

Is it possible for anyone to plug their leaf in and monitor the charge rate for 5-10 mins using a EVSE rated to deliver >=6.6 kW? It is possible the charge rate is decreased with the car put into aux mode which is what i have to have the car state in so that the OBD2 has power. I have a clip on ammeter at work that i will bring home and monitor current with on monday with the car in the full off state and i will check my voltage today.

Thanks!

 

[cwerdna]

I was under the impression the EVSE was basically just a glorified contactor that receives a signal from the car to close the contactor when requested. I didnt think it had the ability to regulate current flow, i thought it was the on board chargers responsibility to regulate current flow. The chargepoint charger i went to yesterday says its max output is 6.6kW according to the app. Thats just a value displayed on the specific charging station, not a real time value.

Is it possible for anyone to plug their leaf in and monitor the charge rate for 5-10 mins using a EVSE rated to deliver >=6.6 kW? It is possible the charge rate is decreased with the car put into aux mode which is what i have to have the car state in so that the OBD2 has power. I have a clip on ammeter at work that i will bring home and monitor current with on monday with the car in the full off state and i will check my voltage today.

Common commercial power is only 208 volts. On ALL the Chargepoint L2 EVSEs at work, including the legacy CT2000 series and current CT4000 series (http://www.chargepoint.com/support-guides/), my '13 Leaf SV (and my leased one) only pull ~5.7 to 6.0 kW out of the "wall" (per Chargepoint app on iOS and their web site, and in some cases their front panel display). I don't generally monitor the charging power in Leaf Spy while using those.

The most I've ever seen any car pull from the "wall" on those is ~6.2 kW, which makes sense (208 volts * 30 amps = 6240 watts = 6.24 kW). The cars in question were Tesla Model S, since they have at least a 10 kW OBC.

When when only had a small # of Chargepoint EVSEs, the Chargepoint techs that came out confirmed our voltage to the stations is 208 volts.

I've used free public L2 charging (30 amp Clipper Creek EVSEs) at http://api.plugshare.com/view/location/7989. IIRC, from Leaf Spy Pro, where on one of the charging screens that has (a.b/c.d kW), I don't think those values have ever gone above ~5.5 kW for me. I suspect their supply voltage is also only 208 volts.

It might also only be about 5.5 kW at max per Leaf Spy on the earlier Chargepoint EVSEs, as well.

From the Leaf Spy manual (that I requested via email). "The first title line displays two power numbers in kW. The first number is the power in kW going into the battery pack and the second number is the power the charger is reporting." I guess that makes sense there's fixed overhead (charging losses). Definitely not all the energy coming out of the "wall" makes it into the battery.

I'd imagine Turbo3 (author of Leaf Spy) has only figured out all these values via trial and error since I don't think Nissan's ever documented any of these messages on the CAN bus.

I have no L2 charging @ home, so it's likely rare that I've ever charged at 240 volts.

I will double check when I get a chance at http://api.plugshare.com/view/location/7989 and at my work's Chargepoint EVSEs, but it might not be for a few days or a week.

 

[davewill]

Yes, sorry. These charge numbers are using leaf spy and is the sum of the charge into the battery as well as any aux power being drawn by other devices. So it would be the total supplied by the EVSE. ...

No, it wouldn't. The OBC is not 100% efficient, and there are other overheads while charging. You should expect the charge to be no more than 85% efficient at 240v. Assuming a max of 6.0kW from the wall, 6.0kW * 0,85 = 5.1k into the battery. I'd guess that LEAFSpy is getting at least some or all of the overhead, but none of the charging inefficiency, so you're seeing 5.5kW.

 

[GerryAZ]

Ninjarider,

The 5.5 kW charging power (indicated by Leaf Spy) you posted for your Leaf seems a little low since your Clipper Creek EVSE should provide a pilot signal to allow the car to draw up to 32 amperes.

I just started L2 charge on my 2015 SL at home and made the following measurements:
Leaf Spy indicates 6.0 kW (saw it drop to 5.9 briefly) most of the time.
Gid Meter varies between 5.7 and 5.9 kW, but seems to indicate 5.8 kW most of the time.

EKM revenue-accuracy meter on input to AeroVironment EVSE:
26.4 amperes
243.9 volts
6450 to 6460 watts
1.00 power factor

Note that the AeroVironment EVSE (AV EVSE) provides a pilot signal which allows the car to draw up to 30 amperes. The Leaf will draw more current when the voltage is lower to keep input power the same (up to the pilot signal limit). The 2011 would charge as fast on 208 volts nominal with the AV EVSE as it would on 240 volts nominal because it could draw as much current as it needed for its 3.3 kW charger output. The 2015 charges slightly slower on 208 volts nominal with the AV EVSE because the current is limited to 30 amperes (which is 6240 watts at 208 volts).

Gerry

 

[cwerdna]

^^^
GerryAZ, what if you charge on a 208 volt 30 amp L2 EVSE?

 

[GerryAZ]

^^^
GerryAZ, what if you charge on a 208 volt 30 amp L2 EVSE?

The same AeroVironment EVSE and meter will show the car drawing 30 amperes and 6230 to 6240 watts (at nominal 208 volts) when I charge at my workshop garage.

Most public Blink L2 EVSEs have their pilot signal set to 24 amperes or less to minimize the possible heating of crimped connections in the J1772 plug. Therefore, they are limited to 5 kW or less at the plug. The last time I used a Blink L2, Leaf Spy indicated 4.3 kW, but I did not have a way to measure input current and voltage.

Gerry

 

[cwerdna]

^^^
GerryAZ, what if you charge on a 208 volt 30 amp L2 EVSE?

The same AeroVironment EVSE and meter will show the car drawing 30 amperes and 6230 to 6240 watts (at nominal 208 volts) when I charge at my workshop garage.

That's surprising. I've never seen my '13 Leaf SV (current or former) nor any '13+ Leaf draw over ~6.0 kW on our 30 amp Chargepoint L2 EVSEs at work @ 208 volts, per Chargepoint techs. On the older CT2000-series stations, we can view the charge rate on the display. I also sometimes start sessions for other vehicles, including other '13+ Leafs (and '11 and '12s) and sometimes a Tesla Model S. Regardless of the series, 5.7 to 6.0 kW is typical for '13+ Leaf and ~3.8 kW for an '11 or '12 and ~6.2 kW for a Model S.

We recently had many dozens of Chargepoint L2 EVSEs added at a new set of buildings and I've not spoken to the techs since this addition, but the output values out of the EVSEs (at old location and new locations) I'm seeing remain the same. All these values come from either the display on the EVSE or Chargepoint's mobile app or web site.

Most public Blink L2 EVSEs have their pilot signal set to 24 amperes or less to minimize the possible heating of crimped connections in the J1772 plug. Therefore, they are limited to 5 kW or less at the plug. The last time I used a Blink L2, Leaf Spy indicated 4.3 kW, but I did not have a way to measure input current and voltage.

Yes, I know about Blink EVSEs limiting due to bad crimps in the crap Rema handles. I didn't know the max amperage they're being limited to and I've never used a Blink EVSE in my life. We also have no Blinks @ my work.

 

[minispeed]

I notice my leaf spy numbers when charging jump around when I turn the climate control on or off. I would have expected it still draw the same power just put less into the battery but when I've tested for a few min off then a few on then repeat you can see the graph going down each time it's on and jumping back up a bit when it's off.

 

[GerryAZ]

I notice my leaf spy numbers when charging jump around when I turn the climate control on or off. I would have expected it still draw the same power just put less into the battery but when I've tested for a few min off then a few on then repeat you can see the graph going down each time it's on and jumping back up a bit when it's off.

Mini speed,
I think the Leaf Spy numbers indicate power into the battery (not input power to onboard charger). The climate control running reduces power flow into the battery if the onboard charger is running at maximum output or if it is limited by the EVSE pilot signal. The onboard charger will increase its output if possible to compensate for the climate control use (if charge rate has dropped because battery is approaching full charge, the charger can increase its output to cover the climate control and keep the same power flow into the battery).

Cwerdna,
The Leaf onboard charger respects the pilot signal and will not exceed 30 amperes regardless of the voltage. Perhaps the voltage under load is slightly low at your Chargepoint chargers. My garage unit is close to the supply transformer so the voltage is usually a little higher than 208 (typically 210 to 212).

Gerry

 

[Ninjarider1978]

Sorry about being delinquent on the replying.

I have done a bit more testing and have figured out a couple of things. I measured the voltage to my house with minimal load and found 238.5 Vac. Once I had the leaf back home, I plugged it in and forced it to charge starting at 27%. I measured the voltage again (both times at the split receptacle in the kitchen) and found it had dropped to 233.5 Vac. I checked out the leaf spy app but this time I did it pressing the power button only once with no foot on the pedal (normally I would press it twice). This kept power on the OBD2 and allowed me to monitor charge into the battery without having all the accessories powered up. To my surprise it was 6.15kW into the battery and 0.1kW to aux and it was fairly stable, fluctuating only 200 W. I pressed the power button one more time and it dropped down to 5.6kW. So it seems there is considerable power drawn by the accessories once the power button is pressed twice. That power is not accounted for on the leafspy program it seems. I am going to do some more experimenting with this once my battery is drained down again.

As far as efficiency goes, obviously there is no such thing as 100% but I would hope that when they advertise max charging of 6.6kW that means the charger will output that and the EVSE will supply the full 6.6kW plus the losses, but maybe that's just wishful thinking. I am getting my clip on tomorrow and am going to see what current and voltage is delivered right from the breaker panel.

The leafspy numbers do indicate power into the battery plus load on the aux battery, heater power and AC power. I was noticing the power into battery was changing based on the power required by the other devices mentioned. They always summed to equal a value that would fluctuate every 5-10 secs. I could turn off the heater and quickly see that power being pushed into the battery instead.

Quick question and not really super practical but more for just interests sake. What's the max AC current permitted into the leaf? Could I just go down to 120Vac and try to push 55A into the vehicle? Seems like there is a limit, I am just curious what it is. Also, what is the communications between the OBC and an EVSE? Is it some sort of communications protocol or is it more basically than that?

Mike

 

[cwerdna]

I checked out the leaf spy app but this time I did it pressing the power button only once with no foot on the pedal (normally I would press it twice). This kept power on the OBD2 and allowed me to monitor charge into the battery without having all the accessories powered up. To my surprise it was 6.15kW into the battery and 0.1kW to aux and it was fairly stable, fluctuating only 200 W. I pressed the power button one more time and it dropped down to 5.6kW. So it seems there is considerable power drawn by the accessories once the power button is pressed twice.

Yes, from my Leaf Spy observations, if you want charge the battery quickest, you're best leaving the car completely off: no ACC, ON or READY mode.

Quick question and not really super practical but more for just interests sake. What's the max AC current permitted into the leaf? Could I just go down to 120Vac and try to push 55A into the vehicle? Seems like there is a limit, I am just curious what it is.

Seems like the max is simply 6.6 kW from the wall, so that should be 27.5 amps @ 240 volts. http://www.mynissanleaf.com/viewtopic.php?p=338038#p338038 has a charging graph.

Also, what is the communications between the OBC and an EVSE? Is it some sort of communications protocol or is it more basically than that?

https://code.google.com/p/open-evse/wiki/J1772Basics

There might be more in the .pptx or .pdf file at the bottom of https://code.google.com/p/open-evse/downloads/list.

I would hope that when they advertise max charging of 6.6kW that means the charger will output that and the EVSE will supply the full 6.6kW plus the losses, but maybe that's just wishful thinking.

Think this falls under wishful thinking. See http://www.mynissanleaf.com/viewtopic.php?p=295770#p295770. It seems Nissan became inconsistent/loosey goosey about their OBC wattage ratings.

 

[EVDRIVER]

You can pull more amps at 208-220V but the net kw is about the same or less. Nissan has only been honest about the charger on the 2011-12 which was 3.3 charger 3.8 max load approx...

 

[GerryAZ]

Yes, 2011 and 2012 onboard chargers were rated 3.3 kW output and would draw slightly less than 3.8 kW from the wall under maximum load. 2015 appears to be about 6.0 kW maximum output and will draw a little less than 6.6 kW from the wall under maximum load.

 

[cwerdna]

Common commercial power is only 208 volts. On ALL the Chargepoint L2 EVSEs at work, including the legacy CT2000 series and current CT4000 series (http://www.chargepoint.com/support-guides/), my '13 Leaf SV (and my leased one) only pull ~5.7 to 6.0 kW out of the "wall" (per Chargepoint app on iOS and their web site, and in some cases their front panel display). I don't generally monitor the charging power in Leaf Spy while using those.

The most I've ever seen any car pull from the "wall" on those is ~6.2 kW, which makes sense (208 volts * 30 amps = 6240 watts = 6.24 kW). The cars in question were Tesla Model S, since they have at least a 10 kW OBC.

I actually observed my Leaf pulling a bit over 6.1 kW per Chargepoint's web site (NOT Leaf Spy) on one of the EVSEs at my work today. It's possible the voltage was higher at night or voltage is higher at that EVSE than others. Or, maybe because it was cold outside, the car could draw slightly more? 6.1ish kW is a record for the '13 Leafs I've had.

We now have over 70 J1772 handles spread across 5 different areas at my work.

I've used free public L2 charging (30 amp Clipper Creek EVSEs) at http://api.plugshare.com/view/location/7989. IIRC, from Leaf Spy Pro, where on one of the charging screens that has (a.b/c.d kW), I don't think those values have ever gone above ~5.5 kW for me. I suspect their supply voltage is also only 208 volts.

I used the above free public charging and the second value in the ( ) was no higher than 5.5 kW, when I was watching.