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Discussion Starter #1
Observation on the time to charge display (on a 6.6kW equipped Leaf), when adjusting charge rate on a Mainpine-equipped EVSE.

If the advertised current is > 16A, it will display the 6kW estimated time to charge.
If the advertised current is <= 16A, it will display the 3kW estimated time to charge.

The estimated time to charge is not based on the advertised current from the charger, but an assumption that it's either going to be 3.3kW or 6.6kW - with a gradual slowdown as the battery nears full, and it slows down the rate of charge to balance the packs. If you slow it right down to 6A, then the estimated time to charge doesn't change at all from the 16A charge rate - but I've confirmed via a clamp meter that the car draws just under the advertised current.

So there, once again, the Leaf's instrumentation doesn't tell you half of what it knows.
(It could display actual charge rate on the screen, but it doesn't - it could display what the charger is actually drawing, and how many kilowatt hours have been drawn, but it doesn't)
Likewise, it could display an accurate speedometer, but instead it lies by overreading by 10%, even though the odometer is accurate enough.
 

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I get a higher estimated time to charge displayed when using the 10A brick EVSE compared to using a 16A charge point.
 

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Observation on the time to charge display (on a 6.6kW equipped Leaf), when adjusting charge rate on a Mainpine-equipped EVSE.

If the advertised current is > 16A, it will display the 6kW estimated time to charge.
If the advertised current is <= 16A, it will display the 3kW estimated time to charge.
It is not at all clear to me what you are precisely talking about. I've got a Visia, so I've just got the display on the dashboard; is that what you are talking about, or something that appears on the touch screen? Also my display will give both 3kW and 6kW estimates.

Things change when a charging cable is connected and charging has not started. Once it has negotiated a charge rate with the EVSE, I think it only displays the resulting estimated time to charge. I'm pretty sure the time displayed for 10A (brick) charging takes into account the actual 2.3kW rather than 3kW rate (it also adds a generous time for balancing at the end). If this were not taken into account (i.e., if the car was counting on an unrealistic 3kW), charging of an empty battery would start too late to achieve 100% at the programmed time, but nothing like that ever happened to me.

Maybe you are talking about the estimated remaining time to charge displayed after charging has started. It is quite possible that this is not updated realistically, I never go back into the car to check. If the charging current varies over time, it is hard to predict how much time will be needed anyway (but I thought this was mainly an issue for rapid charging; charging at home I've never noticed my meter showing any less than 2.3kW consumption, until near the end the current switches off and the final pack balancing starts). I believe the only real reason the estimated time to charge is displayed is to know at what time a programmed charge will start; after that it is just charge as fast as possible and hope for the best.

Every gauge in the Leaf is rubbish and inaccurate. What makes that more annoying is that the car is essentially all digital meaning it COULD give exact results but it does not.
That is a common misconception. Being able to display numbers digitally does not imply those numbers are either accurate (when based on fundamentally imprecise measurements like battery SOC) or reliable (when involving a prediction, as the GOM display or estimated time to charge).
 

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Discussion Starter #5
GOM is always going to be a guess, but a speedometer should be able to accurately display speed, especially when it can cross-reference wheel rotations against GPS via can bus from the satnav to automatically adjust for tyre pressures / sizes. Instead, it seems to always add about 10% to the speed.

My experiment setup:
6.6kW Leaf, EVSE with variable advertised power (Mainpine).
Clamp meter on the L1 line to the car set to AC current.

Set EVSE to 16A, start charge. Note dashboard estimated time to full display for 3kW charge. Confirm with clamp meter that car is drawing about 15.5A.
Set EVSE to 6A. Leave for a few minutes. Note that the estimated time to full display doesn't change to reflect the available power. It should be more than double. Confirm with clamp meter that car is drawing about 5.7A

I didn't test what happens with higher currents, because the location I was doing my experiments only had a 16A commando socket handy.
 

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OK, so the estimated time to charge is unlike the GOM in that it does not try to use recent performance to predict future results. My guess it is just basing its calculations on the maximal power that the EVSE was promising when it first negotiated with the car; if something then starts throttling this power, it might take the result of that into account (charging advanced less than predicted, so more remains to be done), but will continue to hope that the EVSE can get back to its maximal power.

It would be interesting to compare this with setting the EVSE to 6A before connecting to the car. I think in that case the time displayed will be based on that current.
 
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