Question on Installing Level 2 Charger @Home

[Swapsafari]

Hello Everyone,

We just got a delivery of 2017 BMW i3 94ah last week and are absolutely loving it. Glad we made a switch to the EV life. However, it comes with the added expense of installing the 240V outlet and getting a level 2 charger to make life easier. I have taken some quotes from the local electrician and they are charging me $350 to get the plug installed. For those of you have done this before, I wanted to check, what amperage should I be telling the electrician for this car? I remember from my research on this car earlier that 50 amps is good with 240V but wanted to check? Can anyone confirm what amps are needed? I believe that means it will have a 1450 plug.

I just discovered the "shop" tab on this forum that talks about all the EVSE available in the market. I know it has got a big sliding scale on price. Is there a sweet spot or a good charger that this community recommends based on their own experience?

Also, currently, I am using the regular outlet (120V) and the car is taking too long to charge. I would say for keeping it plugged in for about 10 hours, I would see a jump of 20%-25% charge from where it was which seems really slow? Is there any setting in the car that I need to change for it to charge faster on 120? I know under eDrive I saw charge rapidly which is what my car is set on but wanted to know if there are any tricks to faster charging.

Thank you for your help!

[EvanstonI3]

All wiring and outlet should be for 50 amp circuit.
Breaker should 40 amp.

[BL5]

I'd suggest getting a NEMA 14-50 plug installed and a 40A charger (EVSE). Even though our i3's can only take 30 or 32A, this will future proof all you charging at 40A. Currently only Teslas takes 40+ amps. All new production Teslas take 48A max (unless you have a older Model S/X with dual chargers). Although it appears 48A max will be the current standard for a while. Only issue with 48A is generally requires hardwiring.

That's why I suggest a charger with a NEMA 14-50 plug. Chargepoint, Juicebox, E-Grillze, Clipper Creek (and more) all have NEMA 14-50 plugs.

Personally I have a Tesla 48A charger for my Model 3, and two JuiceBox NEMA 14-50 chargers for my BMW i3's.

Yes, it's very confusing.

[Pahaska]

Given that in my house, it required 100'+ of wire through the attic from the service as far from the garage as it could be and still the same house, I settled for a 30-amp service with a 1430 outlet. Because I drive only short distances each day and because believe that slow charging is best for the car, I settled for a 16-amp, 220v charger that puts about 11 miles per hour on the car. A 50-amp service would have been much more costly and was not needed.

I charge about every other day and the battery doesn't get below 70% except for occasionally when I want to run the REx to make sure it is in good order.

[eNate]

... I am using the regular outlet (120V) and the car is taking too long to charge. I would say for keeping it plugged in for about 10 hours, I would see a jump of 20%-25% charge from where it was which seems really slow? Is there any setting in the car that I need to change for it to charge faster on 120? I know under eDrive I saw charge rapidly which is what my car is set on but wanted to know if there are any tricks to faster charging.

On your charging menu there are options for low, reduced, and max IIRC. There's a table in your manual that shows the corresponding Amp flow-thru based on your EVSE. Stock EVSE are either 10A or 12A. There's a label in the back to indicate which you've got.

For your 2017, a 120V/ 12A charge rate will put a bit more than 3.5% back into your battery every hour.

If you're in need of slightly faster 120v charging (like for instance me at work) there are 16A EVSE available that return about 5% per hour to the 94Ah battery, about 50 miles of range over 8 hours. This is my bread and butter charging despite having Level 2 options available, which I rarely use.

[eXodus]

I've went with a direct wire Blink 30a charger for 94ah i3

No Plug installed, just ran the gauge cable directly into the charger. It probably doesn't make that much difference - maybe 50-100$, less but I like the clean installation. The charger sits alone on the wall with no cables or plugs around.



Always charge full in less then 5 hours - but I never charge like from completely empty - usually I plug it in when I got 30-40 miles left.
So putting in roughly 20-25 miles/ hour.

Like stated before - the i3 maxes out at 32A AC charging - so no need to go for 40a or 50A charger.
Yet it's wise to already install bigger cables since most of the money you invest is in labor and not material.

I got full copper 8/3 wiring installed while while a thinner wire would have been sufficient. So I can upgrade to a bigger charger down the road, should need arise.

[3pete]

I think you struck a nice balance to go with an L2 station even if you're not maxing out the i3's chargers... as long as it meets your needs. Jumping to 240v doubles your charge speed with the only cost being an additional slot in your breaker box and if you have a very long cable run (and a short-ish commute) it can make sense to limit your current pull. 30a wiring gives you the option to upgrade to 24a continuous charge if you find your present situation to be inadequate either through a hardware limited 24a EVSE, or a "smart" EVSE with a maximum-current setting.

I would say for keeping it plugged in for about 10 hours, I would see a jump of 20%-25% charge from where it was which seems really slow?

Something seems off here. As @eNate said, on L1 max charge (set in idrive) the provided cable should get you much closer to 40-50% charge boost over 10 hours than 25%.

[alohart]

On your charging menu there are options for low, reduced, and max IIRC.

If your Level 1 charging speed is set to Low or Reduced and you increase the charging speed to Max, be sure to monitor the temperature of the 120 V receptacle and EVSE inlet plug. If either becomes dangerously hot, the plug and/or receptacle could melt which could be a fire hazard. This could occur if the receptacle is old with possibly weakened or corroded contacts or with loose connections to circuit wiring.

[eXodus]

I think you struck a nice balance to go with an L2 station even if you're not maxing out the i3's chargers... as long as it meets your needs. Jumping to 240v doubles your charge speed with the only cost being an additional slot in your breaker box and if you have a very long cable run (and a short-ish commute) it can make sense to limit your current pull. 30a wiring gives you the option to upgrade to 24a continuous charge if you find your present situation to be inadequate either through a hardware limited 24a EVSE, or a "smart" EVSE with a maximum-current setting.

Something seems off here. As @eNate said, on L1 max charge (set in idrive) the provided cable should get you much closer to 40-50% charge boost over 10 hours than 25%.

The BMW charger has 12a x 115v = 1380w - meaning 1.4KW - the battery has 30kwh usable the charger is 90% efficient 30/0.9 = 33kwh for a full charge

33kwh / 1.4kw = 23.8h for a full charge

Like you said - the cheapest for faster charge would be just change that one outlet the car sits on to 240v - yet many times outlets are daisy chained and it's not possible. You would be only paying for the outlet and another breaker.

But very often - there are like 5-10 outlets on that circuit and it's not possible.

So the options are - just live with the slow charge,
Enjoy the fuel savings for another 2-3 months - save up and just do it correctly and get the bigger charger installed

[labtebo]

https://drive.google.com/drive/folders/ ... sp=sharing
as what the others have shared:
For a nominal charging of 32 A - a 40A max circuit is more than enough.
40A circuit - 40A ckt breaker, 50A ampacity wire (90C #8awg for short runs, #6 for long runs), i recommend adding a lockable disconnect adjacent to charger ( i added a timer to ensure charging only during time of use periods)