Jki3
Posts: 11
Joined: Wed Jun 27, 2018 9:53 pm

Scheduled charging using i3 settings and departure time

Sun Jul 08, 2018 6:32 pm

2018 Rex

My short experience with scheduled charging is that a departure time must be set in the idrive settings to enable a time period in which the i3 charges at home at the lowest utility rate. Being that I have TOU rates, that would be 12am-6am.

After reading some more posts, should I infer that since I have set a scheduled departure time, the i3 will precondition the battery and climate for that departure time?

I set the depart time simply because I thought it was necessary in order to use the charging timer in the i3, and not because I have an actual regular depart time. My concern now after reading some more posts is that there will be a daily and regular preconditioning activity initiated by the i3 that will consume battery capacity, or electricity when plugged in, when I actually don't want that to occur.

Anyone with specific info on that one?
Thanks

alohart
Posts: 1431
Joined: Sat Nov 01, 2014 7:36 pm
Location: Honolulu, HI

Re: Scheduled charging using i3 settings and departure time

Mon Jul 09, 2018 2:38 pm

Assuming that the 2018 i3 works like earlier models in these respects, this article should answer some of your questions. Unfortunately, it refers to the iRemote app that has been deprecated in the U.S. in favor of the BMW Connected app which has a different user interface and somewhat different functionality, so references to iRemote in this article don't always apply to BMW Connected.

Our i3 doesn't have the heated seat and battery pack heater option because these capabilities aren't needed in Honolulu. I have never enabled battery pack preconditioning to cool our battery pack because it is never hot enough where our i3 parks overnight to make preconditioning useful. I have never used the low-cost charging option because it has been very buggy in various i3 system software releases, so I have used the reliable charging start and stop time functionality of our EVSE instead.

Setting a departure time is required for cabin and battery pack preconditioning and for low-cost charging. It is understandable why this would be true for preconditioning, but less understandable for low-cost charging. Apparently, the i3's system software tries to guarantee a full charge by the set departure time, so it will start charging prior to the start time of low-cost charging if necessary.

Also, even with low-cost charging enabled, charging would start immediately if the battery pack's charge level is "too low". If this occurs, the proper behavior would be to charge only to a "high enough" charge level at which point charging would stop until the start of the low-cost charging period or until the time required to ensure a full charge by the set departure time. Buggy implementations have prevented this from working as designed.

As one can imagine, there are many opportunities for software bugs to result in incorrect behavior. BMW has attempted to make the charging behavior so foolproof that it is difficult to understand in addition to implementing a user interface that isn't as good as it could be.

Preconditioning and low-cost charging can be controlled separately, so you should be able to enable low-cost charging without enabling either cabin or battery pack preconditioning.
Aloha,
Art

2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE

jadnashuanh
Posts: 4161
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: Scheduled charging using i3 settings and departure time

Mon Jul 09, 2018 3:30 pm

If you have any home automation, and your EVSE will work right being plugged in, but it's power removed, it would be easy to setup the home automation system to turn power on to the EVSE on a schedule, or on demand, if it is at some other time. There are devices that will work on high current 240vac loads. NOte, though, that not all EVSEs will work right if plugged into the vehicle when power is applied.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

Jki3
Posts: 11
Joined: Wed Jun 27, 2018 9:53 pm

Re: Scheduled charging using i3 settings and departure time

Tue Jul 10, 2018 9:50 am

Thanks for the info fellow members.

Just spoke with BMW genius and apparently in order to use scheduled charging via the idrive control, departure time must be set. I was informed that if departure time is set, then climate and battery preconditioning is automatically performed and there is no way to disable that.

I expressed to the BMW rep that it is unbelieveable that the two functions are not able to be configured independently. Being that I am located in SoCal, and the avg temp is 73 it seems, I don't imagine that there is too much power being used to condition in my situation. Nevertheless, I'm still annoyed that power is being each and every day to condition the car while the scheduled charging function is active.

The rep mentioned that others have voiced the same concern and that a software update to address that is "possible". 4 model years since the i3 introduction and functionality is still what it is, so I'm not holding my breath.

jadnashuanh
Posts: 4161
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: Scheduled charging using i3 settings and departure time

Tue Jul 10, 2018 1:07 pm

You cannot precondition (delayed) the cabin conditioning without enabling the departure time which does the batteries...but, you must check the box after setting a departure time to also condition the cabin, so there is a little choice involved. With the app, you can start cabin conditioning, but that starts immediately, there is no way to delay it.

But, if your EVSE will restart properly, you can use home automation to turn it on when you want. Some EVSE's have logic in them that will allow you to set time windows...most do not.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

alohart
Posts: 1431
Joined: Sat Nov 01, 2014 7:36 pm
Location: Honolulu, HI

Re: Scheduled charging using i3 settings and departure time

Tue Jul 10, 2018 1:52 pm

Jki3 wrote:Just spoke with BMW genius and apparently in order to use scheduled charging via the idrive control, departure time must be set. I was informed that if departure time is set, then climate and battery preconditioning is automatically performed and there is no way to disable that.

I expressed to the BMW rep that it is unbelieveable that the two functions are not able to be configured independently. Being that I am located in SoCal, and the avg temp is 73 it seems, I don't imagine that there is too much power being used to condition in my situation. Nevertheless, I'm still annoyed that power is being each and every day to condition the car while the scheduled charging function is active.

Unless this has changed in 2018 models, low-cost charging and preconditioning are independent of one another. Both require a departure time to be set, but on our 2014 BEV, I could low-cost charge without preconditioning (2 separate iDrive checkboxes) or vice-versa. However, I don't see a way in iDrive, the deprecated iRemote app, or the BMW Connected app to set delayed cabin preconditioning without also enabling battery pack preconditioning. However, I could immediately precondition just the cabin without a departure time set.

BMW's top electric vehicle technical services manager in the US stated that when battery pack preconditioning is enabled, "the battery is warmed or cooled to bring it close to or within the optimal operating range of 25-40C (77-104F)." David Bricknell's excellent book, Electric Vehicles and the i3 (60Ah and 94Ah), available at Amazon or Apple's iBooks, states that battery pack preconditioning will heat a cold battery pack to only 50º F (10º C). Others have confirmed this. I haven't found information about to what temperature battery pack preconditioning would cool a hot battery pack. But it's probably safe to assume that if one wanted to set delayed cabin preconditioning in a moderate climate, battery pack preconditioning would likely not occur because the battery pack temperature would almost certainly be within its optimal operating temperature range.
Aloha,
Art

2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE

jadnashuanh
Posts: 4161
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: Scheduled charging using i3 settings and departure time

Tue Jul 10, 2018 8:52 pm

I installed an inline meter to my EVSE, and I can tell you that it peaks at over 20A (on 240vac) when cold out and in the battery conditioning period near when also preconditioning the cabin. Considering that the battery warming element is 1Kw (about 4A at 230vac), the rest is cabin conditioning and inefficiencies in the on-board systems. Cold probably is worse than cooling if it's too cold for the BEV's heatpump...the REx will always be using resistance heating (mine's a BEV).
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

Jki3
Posts: 11
Joined: Wed Jun 27, 2018 9:53 pm

Re: Scheduled charging using i3 settings and departure time

Wed Jul 11, 2018 6:10 pm

alohart wrote:

Unless this has changed in 2018 models, low-cost charging and preconditioning are independent of one another. Both require a departure time to be set, but on our 2014 BEV, I could low-cost charge without preconditioning (2 separate iDrive checkboxes) or vice-versa. However, I don't see a way in iDrive, the deprecated iRemote app, or the BMW Connected app to set delayed cabin preconditioning without also enabling battery pack preconditioning. However, I could immediately precondition just the cabin without a departure time set.

BMW's top electric vehicle technical services manager in the US stated that when battery pack preconditioning is enabled, "the battery is warmed or cooled to bring it close to or within the optimal operating range of 25-40C (77-104F)." David Bricknell's excellent book, Electric Vehicles and the i3 (60Ah and 94Ah), available at Amazon or Apple's iBooks, states that battery pack preconditioning will heat a cold battery pack to only 50º F (10º C). Others have confirmed this. I haven't found information about to what temperature battery pack preconditioning would cool a hot battery pack. But it's probably safe to assume that if one wanted to set delayed cabin preconditioning in a moderate climate, battery pack preconditioning would likely not occur because the battery pack temperature would almost certainly be within its optimal operating temperature range.[/quote]

Took another look at the idrive settings for charging and I think you might be right wrt setting charging schedule and precondition separately. My guess is that separating battery and climate precondition separately might be the task that can't be separated. Either way, a departure time must be set so I think it applies to both.

EVMan
Posts: 245
Joined: Sat Feb 25, 2017 4:31 pm
Location: USA, CA

Re: Scheduled charging using i3 settings and departure time

Thu Jul 12, 2018 6:23 pm

Since i use Time of use charging at night , i am forced to set departure time.
When doing public charging , i need to change 'delayed charge' to 'charge immediately'
The car does start to charge, But the charge completion time still is dependent on the departure time, to next day .
I think that is incorrectly being displayed.

After these observation , which do not make sense to me , i have given up on the BMW software , making any sense or using these features as part of their QA.
2016 22KWH Rex ( Lease to Return ) ~ Model 3 Dual Motor, Long Range ( Wait-listed )
2017 33KWH Rex
Solar ToU Plan

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