Poll: How accurate is your END-only charging timer?

[LEAFer]

Last night's 80% End-Only timer finished 18minutes "early". IMHO that's rather closer to the end-time than prior experience, but then again, we usually charge to 100%, and that one varies anywhere from 1-1.5hours, but I've also seen 50 mins and 31mins. Be aware ... there appear to be other variables at work, especially as the battery ages/degrades. Some of those variables seem to include a) SOC at charging start; b) temperature; c) whether you've seen 9/12 bars at 80%; d) balancing; e) other ?? .

BTW ... the reason we charged to 80% last night: I was able to borrow a GID meter. I will post results elsewhere as well later (after 100%), but might as well do it here too:

End-Timer: 07:00 Actual Notification: 06:42 10/12 bars.

At 07:30: OAT (per LEAF): 52F (nearby weatherstation: 48F). 27,790 miles, 12 SOC Bars;
Gids: 213 @ 385.5 Volts. GOM: 68 miles, 5TB.

ChargePoint recorded every 5 minutes. At 04:27:23 = 0kW; between 04:32:23 and 06:42:24 between 3.71 and 3.68kW, and at 06:47:24 = 0 kW (note however that this time clock is not sync'ed with above times). Total 8.124kWh. (I *think* it started around 4 or 5 bars, and I forgot to record the # Gids. )

 

[RedMapleLeaf]

Yes, I turned the climate timer completely off.

I think you figured it out!

I had the opportunity to experiment today. I disabled both Climate timers and the LEAF finished charging only 30 min ahead of its scheduled time this morning. Apparently it's not enough to just have the climate timer disabled for the day in question (which I do all the time) but it has to be completely disabled by turning both timers off.

That is really strange (and I believe unwarranted) behavior. Even if the car is attempting to finish charging before it's going to turn on the climate control, it's way overestimating the climate control time.

I've had the same experience. I've tried turning the Climate Control Timers off as well, and I mean completely off. Disabled, none set. My charging end time went from ending 3 to 3 1/2 hours before the programmed charging end time (with CC timers on) to 30 minutes before, which is more like what I would expect. I agree that the very early charge finishing (if CC timers are on) is unwarranted. The car only needs 15 or 20 minutes max to pre-condition the car. Plus, I had my end time set to 4:30 am and the CC set to 5:30 am, which is more than enough time to prevent interference. Also, I set charging as the priority, so it should really ignore the CC timers anyway.

I'm glad I found this out, as I can now more accurately predict when the charging will happen (esp. to avoid leaving the car in a high SOC for longer than necessary). Unfortunately, I have to initiate the CC remotely via iPhone, but this isn't so bad. In the morning (when it's the most useful) I do it while brushing my teeth, and it works out well. Unless Carwings is down again...

MNL forum comes through again!

Renny

 

[Stanton]

I've had the same experience. I've tried turning the Climate Control Timers off as well, and I mean completely off. Disabled, none set. My charging end time went from ending 3 to 3 1/2 hours before the programmed charging end time (with CC timers on) to 30 minutes before, which is more like what I would expect.

I too have verified this phenomena: enabling CC cuts a couple of hours off my "charge stopped" time. However, I only pre-condition (heat) in the winter, so having the car at a higher SOC isn't really as critical when it isn't hot out (e.g. < 6TBs).

 

[TonyWilliams]

The Rav4 is just as nutty as the LEAF with the end timer. I only have an end timer (there is not a start timer) so you'd think they'd have a really good one !!!

This morning, a 100% "range" charge for 6am departure (when the preheat/cool also starts) ended at 1:30am. I'm not even using the full power of the charger (currently a 30 amp Blink instead of 40 amp that the car can handle).

a) SOC at charging start (really low)
b) temperature (60F-70F with TMS.. no factor)
c) whether you've seen 9/12 bars at 80% (well, can't compare... show 16 at 80%)
d) balancing (I think this is the problem)
e) other ?? . (It's a brand new 41.8 kWh Tesla battery, so I don't think aging)
f) climate control timer (TBD)

My wife drove the Rav4 90 miles to Riverside, showing 30 miles remaining, and now it's clicking off 6.911kW on the 208v/30amp ChargePoint. About 20 miles gained per hour charging (6.9*0.85 charger efficiency) = 5.86kW*3.4 miles/kWh = 20 miles per hour. So, three hours charging plus whatever reserve she wants will get her home. I think her meeting is about 4 hours.

ChargePoint is $0.97 per hour there, so about $4 out-of-pocket for the 180 mile trip (I have solar at home for the initial charge). She will bill at 55.5 cents per mile, or about $100.

 

[DaveEV]

One thing I noticed with the LEAF end-only timer - it always starts on 30-minute intervals based on the end time. I discovered this by reviewing Blink data on the website.

So if you have an end-timer that ends at 6:00am, it will always start charging at X:00 or X:30. If you set the end-timer to 5:50am, it will always start charging at X:20 or X:50.

Looking back at this month's data, charging stops anywhere from 25-60 minutes before the scheduled end time with the majority of events occurring stopping around 45-60 minutes early for me.

 

[planet4ever]

One thing I noticed with the LEAF end-only timer - it always starts on 30-minute intervals based on the end time.

I haven't verified this, but I have always assumed that it uses the numbers from the Charging Time display on the dash. Since those numbers are full or half hours, I would be surprised if it didn't work the way you say.

Ray

 

[dgpcolorado]

I'm glad this thread got bumped because I've been noticing that my end timer seems to be ending way early in recent weeks. I was wondering if it might be due to the change from daylight to standard time. But the experiences of those up thread with having the CC timer on or off explains the phenomenon. Today's charge:

80% end time 8:20 AM, CC timer on
Ended 5:20 AM, three hours early.

Weird, but interesting.

Given this, I think I will kick the end time back a couple of hours when I have the CC timer on.


I agree with what RedMapleLeaf said above: "MNL forum comes through again!"

 

[davewill]

The Rav4 is just as nutty as the LEAF with the end timer. I only have an end timer (there is not a start timer) so you'd think they'd have a really good one !!!

This morning, a 100% "range" charge for 6am departure (when the preheat/cool also starts) ended at 1:30am. I'm not even using the full power of the charger (currently a 30 amp Blink instead of 40 amp that the car can handle). ...

Well, to be fair, I've never seen the LEAF one THAT far off.

 

[Ingineer]

It's possible that they do a worst-case calculation based on the fact that on Level 1/2 you could have as low as 100V/200V (Japanese spec power).

It clearly does read the Pilot initially for it calcs, but maybe it only makes a determination as to what amperage and worst-case voltages.

-Phil

 

[TonyWilliams]

It's possible that they do a worst-case calculation based on the fact that on Level 1/2 you could have as low as 100V/200V (Japanese spec power).

It clearly does read the Pilot initially for it calcs, but maybe it only makes a determination as to what amperage and worst-case voltages.

-Phil

Gosh, it would know the voltage pretty quick after charge initiation. Maybe a sequence to shut down and wait if its not 100v/120v/200/208 and restart at the appropriate time?

 

[Ingineer]

Gosh, it would know the voltage pretty quick after charge initiation. Maybe a sequence to shut down and wait if its not 100v/120v/200/208 and restart at the appropriate time?

Oh, there's thousands of possibilities for improvements in software in the Leaf. I thought this thread was trying to get to the bottom of the inaccuracies of the timer and how it works (or doesn't). It'll be interesting to see how many of these things they've fixed in 2013's.

-Phil

 

[davewill]

Every time I plug in the LEAF when on timer, it always engages the EVSE for a second or so then starts waiting to start. I always assumed it was sampling the voltage so that it could handle end timers properly and report "normal" or "trickle" on Carwings.

 

[Ingineer]

Every time I plug in the LEAF when on timer, it always engages the EVSE for a second or so then starts waiting to start. I always assumed it was sampling the voltage so that it could handle end timers properly and report "normal" or "trickle" on Carwings.

Well, clearly as this Poll shows, it is not adjusting the timers that accurately. I think it only makes a determination based on Pilot and whether or not it's Level 1 or level 2. Sampling voltage wouldn't help in any event for problems like excessive sag.

-Phil

 

[RedMapleLeaf]

There have been suggestions that the car's timers or other heuristics have been set for the 200V used in Japan. Now that I've turned off the climate control timers I've observed the charging end time is much closer to the End Time set in the charge timer. I can further state that, while using 240V at home (Schneider dock) gets me charged about 30 to 50 minutes early, using Phil's EVSE Upgrade at work with 208V (i.e., very close to 200V) gets me charged only about 10 minutes early so very accurate.

Renny

 

[69800]

mine is L2 and ALWAYS ends exactly 3 hours early

 

[RedMapleLeaf]

I use an END-time only charging timer set for 6:30am. I've noticed that the charging actually completes between 2.5 to 3 hours prior to that time. Here is a recent sample of end times:

80% (should be 6:30am): 3:50 3:57 3:54 3:27 4:03 3:33 3:26 3:32 3:25 3:36 3:43 3:43 3:52 3:45

For 100% charges I see about the same thing although it's slightly closer to the end time on average (around 2.5 hours and slightly less consistent).

100% (should be 7:30am): 5:45 4:30 5:24 5:33 5:53 5:33 5:44 4:30 5:44 5:37 5:14 5:22 5:37

Based on anecdotal evidence seen in posts around the forum, it seems like many people have charging that stops much closer to the desired END time, but there are some that experience results similar to mine.

I have a 2012 SL model. I am in the Eastern time zone and all clocks in my car are set to that time zone (and have been since I got the car). It had been suggested that I did not have this set up properly, but I have confirmed. I still wondered if it was possibly time zone related, but one of the people that reported early end times is on the west coast.

FYI, my climate control timer works perfectly.

To determine how widespread this problem is, if anyone else uses END-only timers, could you report your experience here?

Please also comment with your time zone (in case it is somehow related), model year, and any other information you think might be pertinent.

Edit: I thought I could create a poll, but I guess not. Basically what I had in mind was:

If you use END-time only timers, how long before your end time does charging usually stop?
1) 0-30 min
2) 30 min - 1.5 hours
3) 1.5 hours - 2.5 hours
4) 2.5 hours or more

I use only END-time charging timers also. I'm in the Eastern Time Zone, and have checked all the clocks. I have a 2011 SL (higher model) with the QC option (which for the Canadian model is identical to the 2012 US model -- everything heated, cold weather package, etc.

I had exactly the same results as you (finishing 2 to 3 hours earlier) but I found that was with the Climate Control Timer set. Others have posted the same connection. Once I disabled the CC timers, my END-Time charging stopped much earlier to the set time using 240V (about 30 to 60 minutes), and nearly exactly on time when charging at work (208V using Phil's EVSE Upgrade). I would agree with the idea that others have suggested, which is that the timers are calibrated to the 200V Japanese voltage. This might account for the more accurate charging at 208V vs 240V.

This is yet another concession we've had to make -- disable the useful and convenient CC timer in order to get a better handle on charging (and not leaving the battery in a high SOC for too long). Also I should add that charging proirity or CC priority didn't seem to make any difference.

Hope that helps.

Renny

 

[Stanton]

I can confirm this same behavior using an end-only timer (charging finishes ~3 hours early when CC timers are set and <1 hour early when NOT set), but here's the thing: I only pre-heat in the winter, when a couple of additional hours sitting at high-SOC shouldn't hurt; I NEVER pre-cool in the summer (at least while plugged-in in the morning). Having said that, I almost never charge to 100%, but the point still stands.

 

[smkettner]

Every time I plug in the LEAF when on timer, it always engages the EVSE for a second or so then starts waiting to start. I always assumed it was sampling the voltage so that it could handle end timers properly and report "normal" or "trickle" on Carwings.

It may sample voltage but mine will not adjust time to the new pilot signal. When using V1 upgrade on the road the L2 charge time is set longer than the 16a L2. Even after the sampling at plug in LEAF start time is still based on 12a 240 time rather than the 16a 240 time.

 

[dgpcolorado]

I use only END-time charging timers also. I'm in the Eastern Time Zone, and have checked all the clocks. I have a 2011 SL (higher model) with the QC option (which for the Canadian model is identical to the 2012 US model -- everything heated, cold weather package, etc.

I had exactly the same results as you (finishing 2 to 3 hours earlier) but I found that was with the Climate Control Timer set. Others have posted the same connection. Once I disabled the CC timers, my END-Time charging stopped much earlier to the set time using 240V (about 30 to 60 minutes), and nearly exactly on time when charging at work (208V using Phil's EVSE Upgrade). I would agree with the idea that others have suggested, which is that the timers are calibrated to the 200V Japanese voltage. This might account for the more accurate charging at 208V vs 240V.

This is yet another concession we've had to make -- disable the useful and convenient CC timer in order to get a better handle on charging (and not leaving the battery in a high SOC for too long). Also I should add that charging proirity or CC priority didn't seem to make any difference.

Hope that helps.

Renny

While I see the same thing: end-time-only charging finishes several hours early with the CC timer set, there is no need to turn off the CC timer to get a charge ending closer to departure time. I just set my departure time an hour or two after I plan to leave. I set the CC timer at departure time or a bit later, depending on how warm I really want the car—the default 77ºF is much too warm for me in winter.

Having the charging finish a couple of hours early isn't that big of a deal, but it certainly isn't difficult to just push back the end-time a couple of hours.

 

[ttweed]

I have a 2011 model and a Blink EVSE. I never set any CC timers, just start CC remotely if I want it in the morning. I usually charge to 80% between midnight and 5AM, which is my "super off-peak" period of $.07/kWh electricity, using timer 1 on the car. I have timer 2 set to 100% and an "end time only" of 5:00AM. On the days when I use that timer 2 with end time only set, the car almost always ends charging within 1 hour of the set end time, sometimes a few minutes more, sometimes a few minutes less. I have never seen it end 2-3 hours early.

YMMV,
TT