upgrade charging

[trumpetdoug]

I looking into putting in a 220v 40 amp service in my garage. Just checking to see if this is indeed what I need for a Level 2 charging system.

I have a 2017 i3 REX. and it does take nearly forever to charge with the regular supplied cord.

Also would any of you have recommendations on level 2 chargers to purchase. The BMW dealership I work with, wants around $1000.00 for theirs. I'm hoping I can find one less expensive than this?


And thoughts / advice are greatly appreciated.

Doug - out

 

[Anonymous]

I put in the EVoInnovate EVSE.
https://www.amazon.com/EVoCharge-EVoInnovate-Electric-Charging-Adjustable/dp/B07BKMX3NL

Made in the USA by a company that mainly builds commercial/public charging stations for office and apartment complexes, so figured it would be well-made, and it is UL listed/tested. Plain-Jane, no wi-fi or bells and whistles - but does what I wanted it to do - fast-charge the car. After a year of use, no issues at all. A 40 amp service will support a 32 amp rated charger. The EVolnnovate charger is adjustable up to 32 amps. Since my house is older, with only a 100 amp main panel, I have mine on a 24 amp circuit, and set for 20 amp charging.

I installed it myself following this as a guide for putting in the 220 outlet.

https://www.youtube.com/watch?v=X9ro7Tc2nFI

 

[Neil]

I would recommend a Clippercreek product (https://www.clippercreek.com). I've had the HCS-40 in my garage since 2014 and my i3 has over 70,000 miles, most of them charged in my garage. No issues at all with the EVSE. The unit I have definitely has no bells and whistles, it just charges my car when I need it to. In my locale, the public free charging stations all use Clippercreek units which are weatherproof. They may have newer products since I purchased mine that might be more appropriate to your situation. I have no affiliation with Clippercreek by the way. Good luck in your choice.

 

[jadnashuanh]

Lots of EVSEs out there. I ended up with a Clipper Creek unit about 5-years ago, and it's still working fine. The CC unit is also made in the USA.

You have lots of choices. While the i3 can handle a maximum of 7400W, which at 240vac is a bit under 31A, many people look for a 32A unit in case their input voltage is a bit lower (power = volts * amps and the EVSE announces how many amps it has...the volts are what they are). In my case, my normal voltage is about 247, and have a 30A unit, so I can max out the i3's internal power supply. NOte, the actual ACV-DCV conversion is done in the car...the EVSE is essentially a smart switch.

One other choice you have to make is whether you want to hard wire the unit, or get one with a plug. You might also consider a larger capacity unit for the next generation of EVs that can handle more power. There are some out there today, and more to come later. As battery packs get larger, new designs tend to consider higher current ACV and DCV (not your current issue!) inputs to minimize the recharging time.

I don't know if this is still an issue, but when I bought mine, some of the brands/models had trouble restarting charging if power was interrupted for some reason, so you could end up finding your battery was not fully charged. The CC unit does recover fine after a power outage. At the time, there were people complaining about theirs not restarting without removing the plug from the car and reinserting it. That's not a car issue, it's a potential EVSE issue, that may be rare today...don't know, but I'd ask the company.

 

[trumpetdoug]

So I have hired a electrician to install the 220 40 amp line. Cound anyone explain the pos. and neg. of a 32 amp charger vs a 40 amp?

Also, does anyone know what the electrical cost of using these different chargers would be?


Doug - out

 

[vreihen]

Plan for the future...pull at least a 50A circuit while the cost is just heavier wire and not labor all over again. That will cover a 40A EVSE, which the i3 can't fully utilize but your next EV most likely will be able to take advantage of.....

 

[Fisher99]

I had an unused 40 amp breaker in my garage but needed wiring extended to a different location in my garage. I had the electrician use wire rated for 50 amps for a bit of future-proofing. But my current EVSE (TurboCord) is only rated at 20 amps so he downgraded the 40 amp breaker to a 20 amp. When I asked why, he said that it was potentially dangerous to allow a 20 amp device to be connected to a 40 amp breaker. Makes sense to me. Especially since I can easily swap out the breaker if I ever upgrade to a higher amp EVSE.

 

[eNate]

Plan for the future...pull at least a 50A circuit while the cost is just heavier wire and not labor all over again. That will cover a 40A EVSE, which the i3 can't fully utilize but your next EV most likely will be able to take advantage of.....

Also future-proofing from the standpoint that you may have two EVs you'd want to charge simultaneously with a dual-cord EVSE.

ClipperCreek has a "Share2" system that gangs two of their 40A EVSEs together on one shared 50A circuit, and the units negotiate to split the load in order to charge both vehicles without overtaxing the circuit.

https://store.clippercreek.com/level2/level2-40-to-80/Share2-HCS-50-40-Amp-Level-2

 

[abeln2672]

So I have hired a electrician to install the 220 40 amp line. Cound anyone explain the pos. and neg. of a 32 amp charger vs a 40 amp?

Also, does anyone know what the electrical cost of using these different chargers would be?


Doug - out

Your 40-amp breaker won't be able to sustain a 40-amp charger. Code requires that any device in sustained use on a circuit draw no more than 80% of the max amps. So a 40-amp circuit is perfect for a 32-amp charging unit (which, conveniently, is what the BMW maxes out at anyway). I'm using a 32-amp Mustart that I bought on Amazon for $299 and it's been flawless. Great reviews, and they sell all amp variations.

As someone else said, it's probably a good idea to have the electrician install a 50-amp breaker on 6-gauge wire for future-proofing. Very cheap upgrade from 40-amp, 8-gauge and worth it if your next car can charge at a higher rate than the i3.

 

[jadnashuanh]

You can put any sized EVSE in that your panel and budget can support but if yiu want to maximize charging your current i3 with 220vac (you sure it's 220 and not 240?), then 7400/220=33.67A, so a 32A device (40A circuit) would not max it out, but would be much faster than the 120vac device.

 

[alohart]

You can put any sized EVSE in that your panel and budget can support but if yiu want to maximize charging your current i3 with 220vac (you sure it's 220 and not 240?), then 7400/220=33.67A, so a 32A device (40A circuit) would not max it out, but would be much faster than the 120vac device.

A fairly minor point, but I believe that the i3's charging electronics are current-limited rather than power-limited based on the results of tests on 4 new 2014 i3 BEV's by the Idaho National Labs. At 240 V, 30.1 A was the maximum charging current measured for a maximum charging power of 7.22 kW. At 208 V, the maximum current measured was 30.4 A for a maximum charging power of 6.47 kW. If the charging electronics were power-limited, the 208 V charging power would be the same as the 240 V charging power. If the charging voltage were 220 V, the maximum charging current would be in the 30.1 - 30.4 A range for a charging power of ~6.6 kW.

Therefore, a 40 A circuit with a 32 A EVSE would maximize an i3's AC Level 2 charging speed regardless of the charging voltage.

 

[jadnashuanh]

The EVSE announces the maximum CURRENT it can support. A properly setup EV will never pull more than that current. So, given power = volts * amps, and the maximum amps is a stated factor, it is the voltage that can be a big variable.

My typical supply voltage is 247vac. With my 30A EVSE, I can max out the i3's charging. Many commercial locations tend to use 208vac. Even if it's a 30A device, you'd only get 208*30 = +6240W and not maximize the charging capacity of the vehicle. The reason the standard calls for current is to protect the wiring to it. You don't want to overload the EVSE or the wiring going to it. The EV will protect itself...think of plugging in a cellphone charger into a typical 15A circuit...it doesn't automatically overload the charger. Try to run a welder, if you could plug it in, it would likely pop the circuit breaker. There's no communication between the source and the user. An EVSE and EV do have some (albeit fairly dumb...the CCS standard calls for a bit more smarts).

Now, how accurate the pilot signal coming from the EVSE is, and the EV's ability to limit it's call to that, there's probably a bit of room for error. From a safety viewpoint, the car should probably not pull up to the max the EVSE announces, in case it's off a bit, too.

 

[3pete]

I'd agree that if you're doing a fresh install, it makes sense to go for a 50amp circuit and wiring right out of the gate, because it should only be marginally more expensive and the wiring is the bulk of the labor you'll pay for (or do), so you don't want to do it again for your next car.

On the other hand, let me ask how important is it to you to "max out" the charge capacity of your i3 (or a future EV with a faster charge rate)?

The "Occasional Use Cord" the car comes with allows charging around 1.4kw. Any level 2 EVSE is going to be a big step up from that. Even at the 'commercial' 208v and 32amp, it's 4.6x faster. Sure, if you upgrade your car in the future, this setup wouldn't be able to max out the new car's charge speed but if you don't find yourself waiting on a charge before you can take a trip right now, it probably won't be an issue in the future with a car that probably will have longer range.

The other thing to remember is that the car charges at its top speed until somewhere around 80%* on the battery. Once you hit that point, the charge rate drops, so you really only benefit from "maxing out" the car's charger until the point that the battery management system becomes the bottleneck and slowly throttles down the charge rate.

The charge graph looks like this where you can see there's over an hour of time where the i3 is using less than the max rate available from the EVSE. A higher powered EVSE won't speed that part up at all

The taller you make that plateau at the beginning certainly speeds up your 0-80% time but the ramp down in the 80-100% range will still take the same time no matter what. This is why many plug in hybrids have charge times similar to the early i3s despite having a batteries that are less than half the size.

So, certainly plan for the future but don't hold off on going L2 if you feel like you have to go straight to an 80amp one or not at all.

P.S. I have a Juicebox 40 and like it, and have had good experiences with the public Clipper Creek EVSEs I've used.

*I believe the buffer where the charge rate slows down is usually in KWH, so for the 60ah i3 it's around 80% but the larger battery i3 (not sure if it's the 90ah or 120ah) it's closer to a 90% charge.

 

[eNate]

On the other hand, let me ask how important is it to you to "max out" the charge capacity of your i3 (or a future EV with a faster charge rate)?

The "Occasional Use Cord" the car comes with allows charging around 1.4kw. Any level 2 EVSE is going to be a big step up from that. Even at the 'commercial' 208v and 32amp, it's 4.6x faster. Sure, if you upgrade your car in the future, this setup wouldn't be able to max out the new car's charge speed but if you don't find yourself waiting on a charge before you can take a trip right now, it probably won't be an issue in the future with a car that probably will have longer range.

This is a good point.

Coming from an exclusive 120v user (that's me), one reason I haven't installed a dedicated L2 charger at home is because I am getting by just fine. There are occasions where I need a quicker boost and my L1 charger is a dual use L2, so I plug it in to a special outlet I wired up and at 10 miles hourly instead of 5.

BUT... when I eventually install a dedicated L2 at the house, I'll max it out (50A circuit), because there have been those rare instances where I need to pile on a lot of charge, fast. And if I'm spending the money, why not just a little more in order to avoid the inconvenience of driving to a public use spot?

My only hesitation is that I'll want to stick with the lower charge rate when I don't need a quick top-up, but I can manage that.

 

[jadnashuanh]

There are EVs out there today that have larger internal level 2 capacities than the current i3, and many others that have a smaller capacity. FWIW, originally, and maybe still, BMW offered various charging levels in other markets. In the USA, we've always had the higher capacity. In places where 3-phase power is common in residences, BMW offers even higher capacity charging on the i3. FWIW, should you decide on a Tesla at some future point, a 50A circuit would not max out the vehicle. As larger capacity batteries become the norm, a higher capacity EVSE may make more sense, but for the normal situation, on a day-to-day basis, a significantly smaller unit should top it out overnight.

Where larger is maybe better is if you want full batteries that evening when you get home from work...you wont have overnight to achieve that. Lacking a CCS unit nearby, a larger EVSE, if you vehicle can handle it could get you there. For those that may not know, a larger unit won't 'hurt' and EV, as the car will limit the maximum it will pull from the EVSE, up to, but never exceeding what it says it has available (so that it doesn't damage or trip the circuit supplying it or the device itself).

 

[eNate]

...or charging two vehicles simultaneously on one circuit.

 

[TahoeGal]

I know this is an older post but in case anyone happens upon this topic I thought I'd mention one more benefit to having a 240V rather than 120V charger. It allows you to take advantage of cheaper time-of-use rates with your electric utility company (for which you'll need to sign up). TOU wouldn't have been very useful when I was charging with 120V because charging took so long, but with 240V if I plug the car in when I get home in the evening and it doesn't start charging until cheap TOU rates kick in at midnight, it's always fully charged by morning.

You can set your i3 to delay charging based on the timing of your cheap utility rates, so even if you plug it in early it will wait. Actually, the charger starts ramping up then displays "waiting for car". It takes 7 blinks of the light around the socket on the car before it shuts off until it's time. (The only trick is to remember to set the i3 to charge immediately when needed, like if you're on a trip and want to stop for charging while on the road.)

I'm happy with my 32-A wall-mount charger purchased from PrimecomTech. https://www.primecom.tech/products/...icle-charging-station-220-volt-20-feet-length. Paid around $400 in Nov 2020. (Looks like $439 now, but out of stock.) This unit looks identical to one sold by Home Depot under the brand Lectron https://www.homedepot.com/p/LECTRON...Electric-Vehicle-EV-Charger32A-650N/315911687 ($430). These are also available cheaper in portable style.

 

[eNate]

That's a good point -- I've seen some fairly narrow low-rate time windows from other members, particularly some EU owners.

In PG&E territory in NorCal, my TOU plan gives me a pretty broad low-rate window: midnight to 3 PM. I wonder if I should feel bad that I charge at work from about 3 pm until 11?

Nah,...