Charging time household plug

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KrisM

Well-known member
Joined
Jul 27, 2019
Messages
61
Location
Belgium, East Flanders
Hi al,

I was talking with the BMW salesman about a wallcharger I would like to buy and He claims that the 94Ah - Rex that I ordered should charge within 4 hours from 0 tot 100% with a normal 220V household plug....

Is this true ?? if so I do not need a special wallcharger that I was planning to buy.
 
I was forgot to say that the salesman said "the car comes with a yellow charger" , I do not now what that means and if or what the difference in charger colors is. Al so want to mention that the car have 4U6 Fastcharging AC and 4U7 fastcharging DC options.
 
The options are the charger electronics built into the car, not what cord(s) they include.

I can't help with what cords they provide in Europe, or what your standard outlet amperage is. Our mains power on this side of the world is a wimpy 120V, and charge times are 12-16 hours on a wall outlet. I know that we can get 4-6 hours on a 230V EVSE, but they only include the 120V cord with our cars.....
 
KrisM said:
I was talking with the BMW salesman about a wallcharger I would like to buy and He claims that the 94Ah - Rex that I ordered should charge within 4 hours from 0 tot 100% with a normal 220V household plug....

Is this true ?? if so I do not need a special wallcharger that I was planning to buy.
No production EV can be plugged into an electrical outlet with a simple cable. There must be an electronic device between the outlet and the EV that can communicate with the EV to determine the charging power that will be provided and to prevent electrocution. In North America, that device is called EVSE, electric vehicle supply equipment. BMW includes a rather low-power EVSE with every i3. For increased charging power, a more powerful EVSE must be used, frequently mounted on a wall.
 
FWIW, the acv charging on an EV depends on a few factors:
- how big the power supply in the car is
- the applied inlet voltage
- the maximum capacity of the EVSE

The EVSE is a fancy, smart, on/off switch. Part of its function is to announce to the vehicle how much current it can provide. The car's part in this is to never try to use more power than the EVSE announces it has. The EVSE also provides ground fault protection, and the car provides a signal that tells the EVSE that it's safe to turn the power on.

Belgium, I think, is one of few places where they provide the i3 with a 3-phase changing capability which could charge the car faster than in most other places. All of the other places I'm aware of utilize a single phase input, whether that's 120 or 240 vac. Well, I heard rumblings about Australia and maybe NZ as well.

In the states, the fastest charge accepted (acv) in the i3 is 7400W, or about 30A at our nominal 240vac generally available. power = volts * amps. Lower the voltage, with the same amps, and less power is available. The maximum amps is the overriding factor as that's the factor announced by the EVSE and what the circuits in the i3 can handle.

At 94Kw in four hours, that's a bit less than 24Kw/hour (note, there is some loss in converting acv to dcv) so, at 24Kw/220v = 109A...the i3 certainly cannot accept anywhere near 109A, nor, are most homes wired up to provide that. Other people have indicated that those that can use a 3-phase input can charge at higher rate (in the range of 10,000 versus 7400), but nowhere near 24,000 unless you're talking about a DC input which you almost certainly won't have in your home unless you want to spend $20K or so and upgrade your power in to industrial standards.
 
Thanks all for the information,

I'm going to wait for the car next week to arrive and then when it is "empty" I will see how long it takes to charge on my provided household connection with the BMW "yellow" charger (what ever that means :) ) This connection I'm using is normal in use for a electric stove or cooking but then on 6mm² wire instead of mine 10mm² wire.

I have in my home 3 fase 240V but it is not connected to the fusebox since we need to pay extra ( a lot ) if we want that and had no need for it before, now I have only 240V monofase. On my lathe on the other hand I have a device, I do not know how it is calling and that makes 3 fases out of the monofase so my lathe could turn left or right.
 
In the meanwhile I have the i3 and had to charge them. It took like forever on the household plug so I ordered a wallcharger taht will arrive monday or tuesday ... I hope :)
 
We use the supplied “brick” a Kopp made one (the good adjustable load one) and have done every night for over three years now, no issues at all, it takes roughly 9-10 hours to charge from almost empty as I recall, although the car is never really near empty so it normally charges to full in just three to five hours.

We were going to get a 7kw wall EVSE installed but frankly it’s just not worth it now.
 
I have the Webasto pure black now and I'm happy with it. Did just some changes to the load cable, I replaced
it with a longer one since the one that was installed was way to short for me.
 
There's nothing "normal" about a 220v plug. That's level 2 and will quire a wall charger (EVSE as someone has stated). Level 1 in the united states is 110v and other countries are probably going to be about the same. That would be considered "normal".
 
sipabit said:
There's nothing "normal" about a 220v plug. That's level 2 and will quire a wall charger (EVSE as someone has stated). Level 1 in the united states is 110v and other countries are probably going to be about the same. That would be considered "normal".

Household voltage in Belgium where the OP is is 230v / 50Hz. Not all electrical systems act the same, particularly for all houses in different countries. ( :D ;) )
 
FWIW, those sorts of supply voltages are available in the USA, too, but often restricted to commercial zones to share the extra costs. But, with enough money, you could probably get it anywhere. Depends on how far you are from higher voltages, which transformers are used, and how deep your pockets are.
 
I use the 110V outlet to charge my i3 or what is known as trickle charging to some. If my i3 battery is completed drained, it's about 22 hours to charge the battery from 0 to 100%. I get about 4 - 5 miles of charge per hour. On my last day of commuting to work I purposely let the battery drop down to 6.5% so the REX will kick in. Then I only drive about 8-10 miles on the REX. I think this is good practice to do at least a couple times a month so that the fluids in REX are being used and the 650 cc engine gets to run a bit. I'm sure most people would not want to wait 22 hours for a full charge on an EV, but honestly my i3 (94Ah) is rarely ever drained with no battery charge left. I just charge it over night maybe 8 - 11 hours or what ever is needed to get back to a full charge or close to it. For me this works out perfectly. Driving my i3 has been a great experience :cool:
 
Our 17 Rex takes 4.5 hours to charge on a dedicated 240V circuit(which was wired with really thick gauge cable and paired with a 50 Amp breaker) here in the US. The voltage on it fluctuates between 225 and 255V. Our i3 maxes out around 31 Amps due to its internal charging limit set by BMW. The math on our charging scenario with our Juicebox Pro 40 works out to about 33.4 kWh of energy pushed into the car including charging losses over those 4.5 hrs of time. Not all 220-240V outlets are created equal and the BMW salesman may have been a bit optimistic. Most existing dryer outlets in garages in the US max out at 30 Amps and are on a 30 Amp breaker, but can only safely provide about 24-26. I wouldn't push them higher for such prolonged periods of time so the charging equipment used should be limited below the max that the i3 can pull (32 Amps) else there's risk involved with wiring and breakers on existing circuits. I suppose there could be significant variance in wiring depending on country, local electric codes n such.
 
KrisM Wrote:

@Geodude why not just code your car that REX can start from 75% ? that is much easier :)

I'm really haven't needed to code my i3 to "hold the state of charge" after 75% because my daily commute isn't far at all. I just charge my i3 at night when I sleep and in the morning my i3 is smiling and ready to go !! Maybe down the road I'll look in to getting one, but for now it's all good. Thanks for sharing KrisM... :cool:
 
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