New Owner Charging Questions

[Fisher99]

I just purchased a 2014 i3. Although I won't be picking it up for a few weeks (it is 700 miles away) I have a couple of questions about charging.

First, I understand that the standard Level 1 charging cord is only about 12' or so in length. It will be difficult for me to park the car that close to an outlet. Is it possible to use a heavy duty extension cord (say, 25') to extend the charging cord length?

Also, what is required if I want to obtain level 2 charging capability? Does something in the i3 need to be physically updated or replaced to gain this capability? And if you do have level 2 capability do you still have the ability of level 1 charging or are you stuck with level 2?

Thanks.

 

[frictioncircle]

Hello Fisher99 –

Congratulations on your purchase! My daily is a 2014 BEV – the early cars are probably the lightest cars that BMW of the 21st century will ever make and they are brilliant little machines.

Assuming you live in North America and have residential 120V service:

Level 1 (120V) charging – in general, yes, you can use an extension cord, though you should buy the thickest and shortest cable that you can possibly use. The longer / thinner an extension cord is the more resistance it has – as resistance increases, the cable gets warmer and less energy makes it to your battery. Go too long or thin and you get into fire-hazard territory.

The extension cord linked in your message is a Level 2 (240V) cable. It will not work for Level 1 charging.

Regarding Level 2 charging: let us know where you live (general geo, nothing specific!). North American cars have built-in Level 1 (120V AC) and Level 2 (240V AC) charging capability. In Europe Level 2 charging is, I believe, an option.

If you have Level 2 charging then yes, you can also charge at Level 1.

Level 3 charging (referred to as DCFC - DC Fast Charging) might be fitted to your i3. Level 3 connections differ depending on what continent you live on.

 

[AndrewDebbie]

I just purchased a 2014 i3.

Also, what is required if I want to obtain level 2 charging capability?

Your i3 has either 3.6kW or 7kW AC level 2 on-board charging. 7kW was standard in many regions but not all.

You need a Level 2 EVSE and a 240 VAC connection. 3.6kW EVSE needs a 20Amp circuit and a 7kW EVSE should be on a 40A circuit. The connection depends on where you live.

In America you can use an electric clothes dryer socket and buy an EVSE that plugs into it. You can also get it hard wired.

In the UK, the EVSE would be hard wired to a dedicated new circuit. I think some people in the EU use a "commando" socket instead of hard wiring.

 

[Fisher99]

Thanks for the quick replies! I live in the USA, in the state of Oregon.

Good to know that I can use a heavy duty extension cord for level 1 120V charging (keeping it as short as possible). Is there an easy way to tell if the car has the 7kW level 2 on-board charging, or just the 3.6kW?

So it sounds like I need a 20 amp circuit for Level 1 charging? I will have to double check but I'm fearful that the closest circuit is only 15 amp.

And good to know that (assuming the car has the 7kW charger) I can plug into a standard clothes dryer circuit. I assume that I would just have to purchase a cord such as this one? https://www.amazon.com/ICEr-J1772-Extension-Cord-amps/dp/B01CF8I4UW/?tag=myelecarfor-20&

 

[Anonymous]

So it sounds like I need a 20 amp circuit for Level 1 charging?

Most house wiring is 20 amps. Check your breaker panel, unless your house is really old, and the panel hasn't been upgraded since the '50s, all your plugs are on 20 amp circuits.

 

[Anonymous]

I assume that I would just have to purchase a cord such as this one? https://www.amazon.com/ICEr-J1772-Exten ... ecarfor-20&

No, that is just an extension cord for an existing 220 charging station. It is for if your charging station comes with a 25 foot cord, which works great when you are parked in your garage, but doesn't quite reach far enough down the driveway, and you need an extension to get it to reach farther.

For 220 charging you will need one of these:

https://www.amazon.com/gp/product/B07BKMX3NL/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

https://www.amazon.com/JuiceBox-Electric-Vehicle-Charging-Station/dp/B07FWSGK1C/ref=asc_df_B07CP7V4TH/?tag=&linkCode=df0&hvadid=312094794461&hvpos=1o1&hvnetw=g&hvrand=13836691106088452417&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9026840&hvtargid=aud-643574997066%3Apla-571637945708&ref=&adgrpid=62497261819&th=1

https://www.amazon.com/dp/B071YDGJYZ/ref=sspa_dk_detail_1?psc=1&pd_rd_i=B071YDGJYZ&pd_rd_w=zkLoL&pf_rd_p=8a8f3917-7900-4ce8-ad90-adf0d53c0985&pd_rd_wg=XZBTY&pf_rd_r=6VNGS8MBM0GGY140Z9F2&pd_rd_r=3bf58992-78bd-11e9-985f-5d3a71b469ca

https://www.amazon.com/ClipperCreek-HCS-40-Charging-Station-Certified/dp/B00TJD0ZW2/ref=sr_1_5?crid=2PM7B8VDWLZLQ&keywords=clipper+creek+level+2+charger&qid=1558109091&s=automotive&sprefix=clipper+c%2Cautomotive%2C163&sr=1-5

 

[Fisher99]

Oh, I get it. I thought I could get a cord that would plug directly into a 220 dryer socket for charging the i3, but you are saying that for 220 charging that I would need to purchase a charging station? That definitely ramps up the expense, so not sure that I will go that route. This will be mostly an around town and short trip car for me, so letting it charge on 120 for 14 hours or so overnight won't really be a problem.

 

[Fisher99]

I just downloaded the i3 manual, to get familiar with the car before I make the trip to bring it home. It talks about having to have an electrician check the electrical outlet before I use it and then I have to manually set the charging rate on the iDrive system in the car depending on the "current strength" of the outlet? This seems cumbersome to me. What if I'm away from home and want to plug into an available 120v outlet? Is it really problematic to leave it configured to "maximum"?

 

[vreihen]

I thought I could get a cord that would plug directly into a 220 dryer socket for charging the i3, but you are saying that for 220 charging that I would need to purchase a charging station?

There are several 220V portable charger options available on Amazon for $200-$300 US, some including travel cases and 120V adapters. Some are 16A, and some 32A. Pick one to match your outlet, and you should be good to go with fast L2 charging (or somewhat fast with the 16A options) .

A full charging station just adds wall brackets, a cord hanger, and possibly some intelligence for data logging to the basic electronics used in the portable cables. A lot of them also come with plug options in addition to hard-wiring, with a caveat that (UL?) regulations prohibit them from putting more than a 15-inch (?) cord on the plug end. If you're not hanging the station next to an outlet, you will need to have an electrician install an outlet.....

 

[alohart]

I just downloaded the i3 manual, to get familiar with the car before I make the trip to bring it home. It talks about having to have an electrician check the electrical outlet before I use it and then I have to manually set the charging rate on the iDrive system in the car depending on the "current strength" of the outlet? This seems cumbersome to me. What if I'm away from home and want to plug into an available 120v outlet? Is it really problematic to leave it configured to "maximum"?

Understanding how all EV charging in North America works might make all of this easier to understand. Some things differ in other markets.

All EV's can be charged with AC power. Due to the unfortunate U.S. decision to install both 240 V and 120 V outlets in residences instead of all outlets being 240 V, two AC charging protocols have been defined: AC Level 1 (120 V) and AC Level 2 (208 - 240 V). Fortunately, the charging port and plugs for both AC Levels 1 and 2 are identical (described in the SAE J1772 standard). The charger in every North American EV is able to be charged with all AC Level 1 and 2 input voltages.

The device used to charge an EV is called Electric Vehicle Supply Equipment (EVSE). EVSE minimizes electrocution risk, negotiates with an EV's on-board charger to deliver the maximum power both support, and limits the charging power to protect the charging circuit. This is why an EV cannot be plugged directly into an electrical outlet using only an electrical cable. An AC Level 2 EVSE usually has a setting that limits the current that it can deliver to protect the charging circuit. However, an AC Level 1 EVSE usually does not.

An i3 allows the maximum charging current to be set in iDrive for both AC Levels 1 and 2. This setting has precedence over any EVSE current limit setting. Because most AC Level 2 EVSE's have a current limit setting, it's generally safe to set the AC Level 2 charging power to "Maximum".

120 V residential circuits usually aren't dedicated to a single use (i.e., a 120 V residential circuit can usually be shared by more than one 120 V load). So even if the 12 A AC Level 1 EVSE included with your i3 wouldn't trip the 20 A circuit breaker itself, other loads on the circuit could increase the total circuit current enough to trip its breaker. If this is the situation with your 120 V charging circuit, you might need to reduce the charging power in iDrive to "Reduced" (9 A) or "Low" (6 A) which would significantly increase the charging time.

The recommendation that an electrician check the 120 V outlet you'll use for EV charging is because many outlets are old, could be corroded internally, could have loose internal wiring connections, etc. Any of these conditions could cause the outlet to generate enough heat to damage the outlet and/or EVSE plug or to cause a fire. For continuous use such as EV charging, the maximum safe current is 80% of the rated current capacity for the circuit component rated for the least current. Even though modern residential circuits are typically rated at 20 A, their outlets are usually rated at only 15 A. 80% of 15 A is 12 A, the maximum continuous current delivered by that outlet. This happens to be the maximum current of your EVSE, so your EVSE is drawing the maximum continuous current that would be safe for a new 15 A outlet.

BMW recommends against using a 120 V extension cord with its EVSE because this adds another set of plugs and outlets that could generate dangerous heat if they're not in perfect condition even if the cord itself is rated for more than 12 A of continuous current. Many EV owners use 120 V extension cords without problems, but the plugs and outlets should be monitored to ensure that they're not getting hot.

The J1772 extension cable that you referenced on Amazon would be a safer way to extend the reach of your i3's EVSE. However, the JLONG is almost certainly safer than those made in China like the one you referenced because, unlike Chinese J1772 extension cables, the JLONG includes all J1772 safety features. Unlike what others have stated, any J1772 extension cable could extend either AC Level 1 or AC Level 2 EVSE's, so it could also be used at an AC Level 2 public charging station as well as at home. However, at ~$200, it might be a theft target at a public charging station. Also, its cost could be applied to the installation of an AC Level 2 EVSE, many of which have cables that might be long enough to reach your i3 without a J1772 extension cable.

All North American i3's include the second on-board charger that increases the maximum charging power to ~7.2 kW (240 V @ 30 A).

A dryer outlet is 240 V which won't work with your 120 V only i3 EVSE. However, an AC Level 2 EVSE with a compatible 240 V plug or plug adapter could be plugged into your dryer outlet. Your dryer outlet is likely on a 30 A circuit which would mean a maximum charging current of 80% x 30 A = 24 A. Even though that's less than the maximum current that your i3's charger can accept, its 240 V x 24 A = 5.8 kW charging power is more than twice as much as your 120 V x 12 A = 2.4 kW i3 EVSE, so your total charging time would be cut in half.

If your 2014 i3 has the DC fast charging option (not all did), it could also be charged using DC power from either a DC Level 1 (up to 80 A or 36 kW) or DC Level 2 (81 - 200 A or up to 90 kW) charger. The charging port would have 2 additional pins below the AC charging pins. An i3 can be charged at up to 50 kW of DC power delivered by either DC charger type without any driver configuration (just plug it in). Some erroneously refer to DC fast charging as "Level 3" charging which doesn't exist.

 

[frictioncircle]

Fisher99... is this your first EV? If so, there's a bit to learn compared to a gas car. EVs have plenty of terminology and if you have general knowledge about electricity that will serve you well.

When you park your i3 and plug in, the box on the wall is NOT a charger, it's an EVSE (Electric Vehicle Supply Equipment).

An EVSE is a barely intelligent power switch. Its primary purpose is to never supply power to your EV until the connection has been verified as safe. It's been said that one could take an EVSE's plug and dunk it into a bucket of water with no repercussions. Try at your own risk, of course!

That said, you've been out driving and need juice. Having found an EVSE, you've connected the power cable from your wall box to your i3. They'll communicate with each other – the car advertises the maximum current it can draw; the wall box states how much power it can supply. The two negotiate the connection after which charging starts.

The actual "charger" lives in the i3. It takes AC from your EVSE, converts it to DC, and applies it to your traction battery.

If you bought a base 2014 in Europe it would have one internal charger as standard. An option was for a second internal charger to double the charging time.

In the US, all i3s were shipped with both chargers. Look up "dual KLE i3" to get more background.

 

[Srivenkat]

Although I am not the OP, I found the responses to be very informative. Thanks.

 

[Fisher99]

Wow! These are terrific responses! Yes, this will be my first EV, so not only the charging procedures but also the terminology is new to me.

I think I'm now comfortable that I will be able to charge with 120v at home. I verified that I have a dedicated 20 amp circuit that currently only powers a small wall heater in the garage. I'm going to have an electrician friend disconnect the heater, which I never use, and install an outlet on that circuit. Maybe have him run it to a new outdoor outlet on the outside of the house next to the garage door.

As for level 2 charging, I now understand that I would want to install an EVSE. Not sure I will go to that trouble as I'm not sure my situation requires quicker charging. I guess time will tell.

I'm still a bit confused as to whether or not this car will have a charger capable of level 2 charging but maybe that will become more apparent when I get the car. I asked the current owner and he just said he didn't know because he had never needed faster charging.

Anyway, you guys are terrific! I am really excited to get started as an EV owner! Counting the days until May 6 when I fly down, take possession of the car, and start my 700 mile adventure home! I've already discussed that trip in another thread on this forum and think I'm good to go!

 

[vreihen]

I'm still a bit confused as to whether or not this car will have a charger capable of level 2 charging but maybe that will become more apparent when I get the car. I asked the current owner and he just said he didn't know because he had never needed faster charging.

Every i3 sold in the USA came with full Level 2 charging capabilities (4-6 hours), but only included the Level 1 (12-16 hours) OUC cable (Occasional Use Charger).

"Level 3" fast DC charging (20-30 minutes) was included standard on all 2015+ USA cars, and was an option on 2014 cars. The fast DC charger uses the two large bottom pins in the charging socket, which AFAIK are not included in the cars lacking the feature:

If you want Level 2 charging, you just need to buy a Level 2 EVSE and have your electrician friend wire a 240V outlet (or hard-wire the EVSE).....

 

[Fisher99]

Thanks for clearing that up for me. Good to know that I should have level 2 capability should I choose to go that route.

Again, this is really helpful information for a newbie to the EV world!

 

[Fisher99]

I've been rereading and digesting these valuable posts. I also have been looking at plugshare.com to see what charging stations are in my area. I see stations listed with various plug options. Is the following correct?

If it says "Wall", I could do a level 1 charge using the cord that comes with the i3.

If it says "J-1772", I can plug the charging station's cord into the i3 and do a level 2 charge.

If it says "NEMA 14-50" I would have to have my own portable EVSE (with a matching NEMA plug) but could then do a level 2 charge.

Am I on the right track?

 

[jadnashuanh]

Yes, you're on the right track.

On the subject of signalling between the EVSE and the car...the EVSE sends out a PWM signal that tells the vehicle attached how much power it has available. It it then up to the car to never try to pull more than that amount. The signal the car sends back is that the plug is attached and latched (if you've got it attached, and press the release button, on any one that uses a power contactor, you'll hear it disengage when you press that button). IOW, the car doesn't send anything back other than an interlock signal saying it's safe to turn the power on. It's up to the car to determine when it's charged, and then it disconnects.

When you lock the car, it also engages a locking pin so that the charging cable cannot be released. Once the car becomes fully charged, it (should) retract that locking pin so the connector can be released. I've found that maybe a squirt of WD40 into the sockets of the car's connector and the locking pin hole once a month or so does help things from having an issue.

Level 3 isn't a valid charging mode for out cars.

The DC fast charge (or CCS) works in a similar manner. But, the acv power pins when a CCS plug is attached become serial data lines that communicate more info to the CCS charging device. A CCS device is a high current, high voltage, variable power supply. The communications from the car tell it the voltage level it needs. FWIW, the i3 can accept up to 50Kw.

One last thing I can think of that is pertinent...these numbers are maximums...that does not mean that all devices, whether 120vac, 240vac, or high voltage DC (EVSE's and CCS units) can maximize the charging rate on the i3...there are lots of EVSEs out there that cannot. FWIW, on the EVSE side, i3s sold in the USA can accept a maximum of 7400W. Power=volts*amps. Lots of public EVSEs are run off of 208vac circuits. 208vac*30=6240W, or about 84% of its maximum charging rate. Also note, the car will start to taper off the charging rate as the batteries approach full...in the case of the EVSE, it's the internal charging circuit that does it. On the case of a CCS units, the car tells the CCS unit to start to limit things.

If you choose to set a departure time and to precondition the cabin, if you use the OUC EVSE that comes with the car, you may not leave with a full charge, as the car can use over 20A warming the batteries and the cabin. It won't try to warm the batteries with a departure time if it is not connected to an EVSE.

 

[Fisher99]

More great info! Thanks!

I just pulled the window sticker online and I see that it includes the "[4U7] DC Fast Charging (Sae)" option, so it seems that the car covers most of the charging bases.

 

[Fisher99]

A couple of questions about the i3's "Occasional Use" charging cord:

Is it waterproof (i.e., can it be used in heavy rain)?

Does it contain a GFCI circuit, or should I provide GFCI on the outdoor outlet that I will connect to?

Thanks.

 

[jag932]

Adding a charging unit to your garage is an expense to be sure. But I have not regretted it for a moment. In fact I totally love that I can just plug in my car with the ease of plugging in my iPhone. I dread it when I have to gas up my wife's car. If I never enter a smelly, disgusting gas station again I will be eternally relieved. I saw it as future proofing. Power for my i3 and power for whatever car follows. Amortized over time and taking in to account the delight it provides me, I wouldn't do it any other way.