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Discussion Starter #1
I have had my 2019 Leaf for 18 months with 17000 on the clock. I charge at home with an EVBox ELvi 7Kw charger.
Just recently I have noticed that some charges on seem to use only 3KW, making timed overnight charges a bit less predictable, leaving with less power than anticipated. I have only noticed this in the last 3 or 4 weeks. Could this be the BMS reacting to cold weather? I have a smart meter so can easily see charge rates. The on-board charging also seems to agree with the 3Kw rate.
Will LeafSpy show up any BMS issues if there are any?
 

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Your post might be better answered over in General Charging Discussion - however, a quick look at the EVBox shows it has dynamic load balancing.

Do you know if you have this feature enabled? It's typically coupled with a energy monitoring clamp on your incoming supply to detect and throttle your charging if you are close to breaching your incoming supply limit due to other load factors such as electric heating, or a smaller incoming supply.

Usually it's the charger that dictates the maximum charge speed, rather than the car - so I would lean toward spending more time investigating there. You should have a 3 year warranty with your installer for support if done via OLEV scheme.
 

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Usually it's the charger that dictates the maximum charge speed, rather than the car - so I would lean toward spending more time investigating there. You should have a 3 year warranty with your installer for support if done via OLEV scheme.
You can set the charging rate in the LEAF also. Have you done that by accident?
 

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You can set the charging rate in the LEAF also. Have you done that by accident?
Do you have a picture showing that? The only setting like that I am aware of controls the estimated charge time screen when the car is not actively pulling a charge - accessed under "Menu" of this screen:


I can't find a direct picture of it - nor can I grab a pic seeing my Leaf is still at the dealer :( Alas - I'm certain it only affects what the time estimates are, and not what rate the car will actually charge at.
 

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LEAF N-TEC 62KW
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I'm sure there isn't a charge rate option, just a charge time. Also, the BMS gradually reduces the charging current above about 85%. I noticed it dropped from 26amps to 12 and then zero for 5mins or so, then restarted at 6amps, paused again and then did a final top up at 4aamp before the charger displayed 'battery full'.
The charger only tells the BMS what the MAX charge rate is by means of a resistor, it doesn't itself control it. On chargers with a user adjustable charging current, other resistors are switched in circuit so the BMW can absorb what is available (otherwise it would overload the charger).
When the BMS is balancing and topping up the last 10% or so, it is this, not the charger that progressively reduces the current.

Here is a link to my charging experience a couple of weeks ago. post 64.
 

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LEAF N-TEC 62KW
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I have had my 2019 Leaf for 18 months with 17000 on the clock. I charge at home with an EVBox ELvi 7Kw charger.
Just recently I have noticed that some charges on seem to use only 3KW, making timed overnight charges a bit less predictable, leaving with less power than anticipated. I have only noticed this in the last 3 or 4 weeks. Could this be the BMS reacting to cold weather? I have a smart meter so can easily see charge rates. The on-board charging also seems to agree with the 3Kw rate.
Will LeafSpy show up any BMS issues if there are any?
You didn't say what the SOC was before you started charging because if it is over 95%, then it's quite possible that only 3kw has been absorbed. Try running down the SOC to well below 80% and see how many kwhs are delivered.
 

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Discussion Starter #8
Here is some info from the SAE which explains the control strategy which uses the two smaller pins in the type 2 socket.
Yes, I understood that the charge point informed the BMS what power it could deliver. I also cannot find any way of changing the charge rate from the vehicle.

"You didn't say what the SOC was before you started charging because if it is over 95%, then it's quite possible that only 3kw has been absorbed. Try running down the SOC to well below 80% and see how many kwhs are delivered."

I always try and charge from below 40-50% and aim for 80%, sometimes aiming for 100% to keep the cells balanced. Trying to decide if this is a EVBox or Leaf issue.

Thanks all for your replies
 

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Do you have a picture showing that? The only setting like that I am aware of controls the estimated charge time screen when the car is not actively pulling a charge - accessed under "Menu" of this screen:


I can't find a direct picture of it - nor can I grab a pic seeing my Leaf is still at the dealer :( Alas - I'm certain it only affects what the time estimates are, and not what rate the car will actually charge at.
I have just seen your prompt at the 'menu' sign. This just takes me back to the main menu system, or is it different on other models?
 

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No there isn't a way to alter the charge rate on the 2018> models, not sure about the mk1 models.
Have you seen the same thing on later charges?
Try using a public 7kw charger to eliminate (hopefully) an issue with your Leaf.
 

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NISSAN LEAF 62Kwh
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You need to check the charge rate that the vehicle is receiving but first you need to check in settings.

To do this go to settings, as below:
G​
141200


Go to EV Settings as below:

141201


Go to Charge Time Screen as below:

141202


Ensure that 50Kw(Quick Charge) is switched to “on” –

141203


Then go to the Charge time Estimate screen, as below it should show “50KW”

141204




Switch off – plug the car into the 7Kw charger and let charging start – switch the car back on and navigate back to the screen above. It will show the current charge rate which hopefully will be 6Kw if less, then the problem lies with the charger
 

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LEAF N-TEC 62KW
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You need to check the charge rate that the vehicle is receiving but first you need to check in settings.

To do this go to settings, as below:
G​
View attachment 141200

Go to EV Settings as below:

View attachment 141201

Go to Charge Time Screen as below:

View attachment 141202

Ensure that 50Kw(Quick Charge) is switched to “on” –

View attachment 141203

Then go to the Charge time Estimate screen, as below it should show “50KW”

View attachment 141204



Switch off – plug the car into the 7Kw charger and let charging start – switch the car back on and navigate back to the screen above. It will show the current charge rate which hopefully will be 6Kw if less, then the problem lies with the charger
NO i don't thin that is how it works. That setting is so the correct charge time is displayed and has no effect on the actual charge current. I know this is the case because for 3 weeks I used the granny charger and then after wiring up the 7kw charger, I left it set a 3kw, BUT the car was charging at 6.6kw. I then reset the display to 7kw so the charge time was accurate. (My charger has a display and shows the charging current and when finished, the kw delivered.)
 

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You need to check the charge rate that the vehicle is receiving but first you need to check in settings
Thanks for sharing this Dave! To confirm - this screen has no bearing on charge limits of the car. As mentioned in the menu item itself it's only adjusting the "Charge Time Screen" - to estimate charge times based on the speed you select whilst not actively charging.

Once you plug in - it will simply show the active power draw (as dictated by the charger), and re-adjust the timings accordingly. It will not reduce the charge speed to that setting. I always leave my Leaf on the 6.0kW setting and it will still happily charge at 47-70 kW on a rapid charger.

@IanRalph - Based on your charging profile of 40-80% you mentioned, if you are not seeing 7kW charging i'll remain with my stance that the issue is likely to originate with the charger or the cable.
 

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correct charge time is displayed
Thanks for sharing this Dave! To confirm - this screen has no bearing on charge limits of the car. As mentioned in the menu item itself it's only adjusting the "Charge Time Screen" - to estimate charge times based on the speed you select whilst not actively charging.

Once you plug in - it will simply show the active power draw (as dictated by the charger), and re-adjust the timings accordingly. It will not reduce the charge speed to that setting. I always leave my Leaf on the 6.0kW setting and it will still happily charge at 47-70 kW on a rapid charger.

@IanRalph - Based on your charging profile of 40-80% you mentioned, if you are not seeing 7kW charging i'll remain with my stance that the issue is likely to originate with the charger or the cable.
Exactly! If he tries a public charger with a tethered and untethered cable he can eliminate any issue with the car and cable. (if it works on an untethered charger)
 

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Thanks for sharing this Dave! To confirm - this screen has no bearing on charge limits of the car. As mentioned in the menu item itself it's only adjusting the "Charge Time Screen" - to estimate charge times based on the speed you select whilst not actively charging.

Once you plug in - it will simply show the active power draw (as dictated by the charger), and re-adjust the timings accordingly. It will not reduce the charge speed to that setting. I always leave my Leaf on the 6.0kW setting and it will still happily charge at 47-70 kW on a rapid charger.

@IanRalph - Based on your charging profile of 40-80% you mentioned, if you are not seeing 7kW charging i'll remain with my stance that the issue is likely to originate with the charger or the cable.
Yes, adjusting the "charge time screen settings" has absolutely no bearing on the charge rate that vehicle receives, it depends totally on the output of the charger.

Adjusting the charge rate in settings is really only an onboard calculator illustration based on remaining battery capacity and one of the three charge rate available for selection. I find the most useful one to select is 50kW so I leave it at that setting, that said, with experience one knows roughly how long a rapid charge is going take, so the charge time estimate is pretty useless in practice, when not connected, what I call a bit of street theatre.

What is more valuable is the charge rate screen when plugged into a charger as it shows the current charge rate after losses. Therefore when plugged into a 3.3Kw Charger it will show 3Kw, so if anyone what to check their charger out put, connect up, start charging and note the resulting given charge rate on the screen.

As previously mention the charge rate will drop after 95% SOC for battery balancing purposes.

When I arrive back, earlier I connected up to the pod point - the charge time screen shows "6KW" going into the battery (6.6Kw's according to the smart meter, so 10% loss through the cable and inverter)


141211
 

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Yes, adjusting the "charge time screen settings" has absolutely no bearing on the charge rate that vehicle receives, it depends totally on the output of the charger.

Adjusting the charge rate in settings is really only an onboard calculator illustration based on remaining battery capacity and one of the three charge rate available for selection. I find the most useful one to select is 50kW so I leave it at that setting, that said, with experience one knows roughly how long a rapid charge is going take, so the charge time estimate is pretty useless in practice, when not connected, what I call a bit of street theatre.

What is more valuable is the charge rate screen when plugged into a charger as it shows the current charge rate after losses. Therefore when plugged into a 3.3Kw Charger it will show 3Kw, so if anyone what to check their charger out put, connect up, start charging and note the resulting given charge rate on the screen.

As previously mention the charge rate will drop after 95% SOC for battery balancing purposes.

When I arrive back, earlier I connected up to the pod point - the charge time screen shows "6KW" going into the battery (6.6Kw's according to the smart meter, so 10% loss through the cable and inverter)


View attachment 141211
 

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Discussion Starter #17
Thanks everyone for the inputs. I will adjust the charge time screen and find a local 7KW and see if there is any difference.
 

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I regularly charge my Leaf at a public 7 kW charger, and watch the progress using QuickLeaf. And I never saw a substantial drop of the charging rate (but I have to say that I almost never charge above 90 %).
 
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