Question on Installing Level 2 Charger @Home

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Swapsafari

Member
Joined
Dec 24, 2020
Messages
17
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!
 
All wiring and outlet should be for 50 amp circuit.
Breaker should 40 amp.
 
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.
 
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.
 
Swapsafari said:
... 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.
 
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.

gyqit5qyld661.jpg


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.
 
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.

Swapsafari said:
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%.
 
eNate said:
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.
 
3pete said:
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
 
eXodus said:
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

Yep. My point was 10h / 23.8h is closer to 40-50% than it is to 25% (it's 43% :geek:). So if someone's getting 25% charge off 10 hrs of charge with the provided OUC, the car must not be set to max charge rate or something else is hinkey.

But OP got an L2 EVSE that solves the charge speed so that makes L1 charging a moot point. :)
 
The vehicle can handle a maximum of 7400W, or 32A maximum current, whichever is larger. Electrical code in the USA calls for not loading the circuit for more than 80%, so a 40A circuit could handle a maximum of 32A EVSE, and a 50A circuit can handle 40A one. Yes, wire is probably a significant portion of the cost as will the labor for a long run.

IF you choose to use a unit with a plug, make sure than when you insert it, it is tight. If it doesn't take much pressure to insert it, the contacts are worn out, and things could overheat, melt, and possibly start a fire. There's usually no good reason to set the vehicle to less than maximum unless where you're plugging it in is shared with some other load and the combination might trip the breaker. Having a large EVSE won't overload the vehicle.

FWIW, on a CCS (dc high voltage charge), the i3 can handle up to 50Kw input, and the input voltage will be somewhere between 360-380 vdc or so, depending on where the batteries are in their charge cycle. When using acv (an EVSE), it can handle much less input power.
 
labtebo said:
https://drive.google.com/drive/folders/1lU7v0uC6439k57hnp4H4kM-TVAEDxsVv?usp=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)

What do you mean with disconnect? My charger has a switch on the side to shut it off and buttons to change when it charges.
This is from the code book:

86-304 Disconnecting means
(1) A separate disconnecting means shall be provided for each installation of electric vehicle supply equipment
rated at 60 A or more, or more than 150 volts-to-ground.
(2) The disconnecting means required in Subrule (1) shall be
(a) on the supply side of the point of connection of the electric vehicle supply equipment;
(b) located within sight of and accessible to the electric vehicle supply equipment; and
(c) capable of being locked in the open position.


Since the chargers here mention neither have more then 60A or 150V to ground (240 is between the legs and 120V to ground) .
So a disconnect should not be required or? - it's ok to recommend one. Especially when the breaker box is far away.

Why do you think you need a disconnect? I mean the small chargers are not serviceable like an Air Conditioner which requires one.
 
eXodus said:
What do you mean with disconnect? My charger has a switch on the side to shut it off and buttons to change when it charges.
If the switch on your EVSE actually turns off power to it so that it is not idling and consuming a small amount of energy continously, a disconnect would not be necessary. True on-off switches are rare on EVSE's. Which EVSE do you have?

I had an on-off switch installed by a licensed electrician according to code adjacent to our EVSE so that our EVSE would not consume energy when not in use. It has an LCD that does not sleep or do anything to prevent burn-in, so I do not want it to always be on.
 
My Blink HQ100
https://blinkcharging.com/products/hq-100/
has a switch on the right side and it sounds like relay is clicking on, after that it takes a few seconds for it to boot and get ready to do something.

It's a very basic charger, no monitoring, no display, only a delay button, 2 4 6 or 8 ours. But with all the incentives I got for less then $300 new.

I only got it for a month, so no idea how longterm quality is. It works and charges the car.
 
My Clipper Creek unit appears to draw about 3W at standby. I'm guessing that that runs the internal power supply that controls the logic board and powers the status LED(s). Not enough for me to worry about it - 20-30 cents a month, depending on your electric rates. FWIW, most electronics fail during turn-on, not during constant use. FWIW, I'm a big fan of having a surge suppressor mounted at the power panel to help everything. I put individual ones on higher dollar things like computers, stereos, etc. A little known brand to residential applications is Mersen...they make mostly stuff for industry, but have some suitable for residential use and without the big name brand, tend to be well priced.
 
jadnashuanh said:
My Clipper Creek unit appears to draw about 3W at standby. I'm guessing that that runs the internal power supply that controls the logic board and powers the status LED(s). Not enough for me to worry about it - 20-30 cents a month, depending on your electric rates. FWIW, most electronics fail during turn-on, not during constant use. FWIW, I'm a big fan of having a surge suppressor mounted at the power panel to help everything. I put individual ones on higher dollar things like computers, stereos, etc. A little known brand to residential applications is Mersen...they make mostly stuff for industry, but have some suitable for residential use and without the big name brand, tend to be well priced.

This looks like a nice charger you got there. Yet 3w standby current is unacceptable these days. Did they put in a ancient transformer as power supply?
I got a laptop which is running at less then 2w idle. With screen on!

I'm in Florida, the lightning capital :p so a surge suppressor is part of my panel and every major appliances has an additional one and computers are behind UPS. I didn't know about Mersen, will look into their products. Thanks.

I got the charger in my garage last month for the expiring tax incentive and Amazon and Blink had been running a promotion. When I get my refund I think I got the L2 charger installed for about only $220 of my money.
 
Just to add context to the EVSE power consumption :

From Clipper Creek:

A: ClipperCreek EV Charging Stations have very minimal standby energy consumption; the standby power draw on the HCS and LCS charging stations is approximately 2 watts.

For comparison, leaving an HCS-40 powered up for about 2 months (50 days) would have the same energy consumption as leaving a 100 watt light bulb on for 24 hours (a very small amount).


From Energy Star EVSE Scoping Report:

The measured standby power [of 13 EVSEs tested] ranged from 1.3 W to 13.4 W and roughly correlates with the amount of features offered by the EVSE including timers, flashlights, and network connectivity.

Clipper Creek units are fairly "bare bones" so two watts isn't the absolute lowest, but isn't awful.
 
You are correct, it's not bad.
sorry I'm a energy efficiency nerd :p I got i3 BEV because I don't see the point of lugging around a engine which I use twice a year

3w x 8766 hours in a year = 26kwh that's more then 100 miles of driving.
 
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