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Discussion Starter · #1 ·
Although I have had my SE since July all my charging so far has been for free at Tesco. Now that this little perk has come to an end I have switched to Octopus Go. I set my first charge session last night but noticed the charging started at about 8.30 pm instead of 00.30 ( I had set times of 00.30-04.30). I reset the departure time to 11am and that did the trick of delaying start charge to 00.30 but there seems to be no way of stopping the charge at 04.30 when my cheap rate ends. I am only using the granny charger and my daily mileage is such that 4 hours at 2.5kwh would be enough for my use. Any thoughts?
 

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2021 F56 Cooper SE Level 2
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MINI's deployment of charge planning is hugely flawed. It assumes that you will be departing when the charge is complete and requires you to set a departure time. It then uses the departure time to calculate how long the charge will take and starts it so that the car will complete charging at departure time. I am not aware of any way to limit charging to a time period and for it to stop before full.

Luckliy I have a home charger that can be programmed to charge within a time period regardless of the car's SOC. You may be able to use a plug-in timer for your granny charger, but be mindful of the current capability of a timer.
 

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I suspect the granny charger is too slow to fully charge the battery in the short time between 0030 and 0430. The car will respect the ‘preferred times’ you set, but the priority is to fully charge the battery. So depending on what battery charge level you start from, and the KWH of the charger, will determine the charge time. You can do the calculation based on the 2-3kw output of the granny charger, the level of charge, and the battery capacity. You will see that you a charge time of 10 hours could be possible.

i have never a problem with the Mini , probably because my off-peak starts at 2330 until 0730, and also the charger kicks out 7KW. Usually the battery is full by 0230 in the morning.
 

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Discussion Starter · #4 ·
Thanks for the replies. Might see if my electrician is able to fit a DIN rail switchable timer into my consumer unit . Other than that I could just charge from 75% to 100% which will take approx 4 hours.
 

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Mini Electric level 2 - 2021
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Exactly as Figbat and Canard says, the MINI only cares about it being fully charged before the departure time - if you are using a low output charger (ie, the 2.3kW "granny charger") it will ignore your start time and start/stop and it calculates when it thinks is right.
The MINI controls the granny charger not what you tell it.
Once you have an independant wall charger you can set it to block the MINI's instruction and only allow 00:30 - 04:30 and with a normal 7.5kW wall charger, even with all the losses in the charging process, a fixed 4 hours will easily get you back to 80% plus from as low as 20%.

Otherwise put a timer on the socket to the granny charger, it's what I did before my "free" wall charger finally got installed. Just make sure the timer is suitabley rated, ie, an immersion heater type timer.
 

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Discussion Starter · #7 ·
Or have him put in a wifi connectable ‘intelligent’ socket that you can control from your phone?

Also you might want to consider charging only to 80%. The last 20% is usually slower in most EVs.
it would be nice if you could set the Mini to only charge to a fixed % but again there seems no way to do this on the App or the on board computer. It really is stupid that the app or car can’t be set to charge only to specific times or to a set %.
 

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It really is stupid that the app or car can’t be set to charge only to specific times or to a set %.
Agree entirely and that's why I initally used a physical timer on my 13A socket supply and now the timer built into my wall charger to block it to the 4 hours.
It seems that BMW logic is achieve 100% whether you want it or not.
I found the same with the high speed chargers I use on my Stansted runs, the display states "waiting for instruction from car" before it starts and I have to press the stop button on the charger once the MINI is at or above 80% otherwise it will aim for 100%
 

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On what we call “level 2” charging, or AC fast charging, it in fact does not slow down after 80% — least not on the single-phase AC here in North America. I highly doubt that it slows down after 80% in the UK or Europe. OTOH, using DC fast charging in temperate conditions, I’ve noted repeatedly that the roll-off begins at around 84%, and drops below AC’s peak of 7.2 kW at around 95%. DC fast charging remains faster than at-home AC fast charging throughout most of the charging range, but because many, if not most DCFC’s charge their fees based on time as well as draw, it becomes inefficiently expensive for most people to continue charging past 85% on DC.
 

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it would be nice if you could set the Mini to only charge to a fixed % but again there seems no way to do this on the App or the on board computer. It really is stupid that the app or car can’t be set to charge only to specific times or to a set %.
Yes this is certainly available on other EV eg our VW … but having said that the battery is almost double the size. I guess most people need the 100% capacity of the small battery. The specific time on the Mini app for me works flawlessly… much better than the VW. The VW has flexibility to set different times on different days and charge to different charge levels.
However…. Because of this flexibility it is overly complicated and has become totally unreliable. The software on the car conflicts with the software built in several models of charger. Result is, even if it does decide to charge at the specified time, it charges at ‘reduced current’ so only at 1 to 2 Kw per hour versus the 7KW available.

Sometimes simplicity is beautiful!
 

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Discussion Starter · #13 ·
The only reason I suggested an immersion heater timer is because they are rated for 3kW continous (standard UK immersion heater).
Most of the plug in "13A" timers would just melt if they actually had to handle 13A for any period of time,,,
Yes the plug in type timers would be a fire hazard.
 

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If it's any consolation, our VW ID.3 suffers from similar problems. The only advantage it has over the Mini (as far as I can see - my wife has just inherited a 2020 Mini and we're still getting to know it) is that we can set the level of charge beforehand. So if it's on 55% and I calculate I can get it to 70% within the cheap rate period, then I just set it to stop at 70%. But it's still far from satisfactory, and actually got worse after the last software update!
[Edit: Forgot to mention that we're still using a granny charger]
 

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Discussion Starter · #15 ·
If it's any consolation, our VW ID.3 suffers from similar problems. The only advantage it has over the Mini (as far as I can see - my wife has just inherited a 2020 Mini and we're still getting to know it) is that we can set the level of charge beforehand. So if it's on 55% and I calculate I can get it to 70% within the cheap rate period, then I just set it to stop at 70%. But it's still far from satisfactory, and actually got worse after the last software update!
If only the SE could do that.
 

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I’ve been following this thread with interest, especially after the end of Tesco free charging. (Thank You whilst it lasted Tesco)

I’m using the 3 pin plug charger lead (granny)
I am on a 7 hour reduced rate from 1am until 8am.

Can anyone please explain the correct settings to enter in to the car or app to take advantage of the reduced rate.

I want to park up in the garage, connect the 3 pin granny charger when I get home, but not start the charge until the reduced times.

I don’t have a time in the morning I need to set off, it’s different every day.

Appreciate any help with this.
Thanks in advance
 

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From what I found before I got my 7kW wall charger, the easiest way that worked for me (but may not be the best way) was to set the departure time to the end of the cheap charging. Doesn't matter what your actual departure time is, it just stops charging at your set "departure" time.
 
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