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If I often used TT-30 plugs, I'd maybe consider something like this 10kW portable CCS charger: 10kw CCS Combo Portable Charger - EV Fast Charger - ShenZhen SETEC Power Co., Ltd.

In theory, you can use this to take in [email protected] and then "DCFC" with that. Here's a demo of this thing (turn on auto-translate subtitles from German->English):

It looks like they're in the ballpark of a few thousand dollars, but could also be handy if you want to hack up a connection from a Tesla HPWC over DCFC, though might be worth getting the 20kW one if you're going to do that on an 80A one, which may or may not be possible with existing adapters.
TT-30 (120V 30A) can only deliver 120 * 30=3.6kW. In actual use it is probably 3kW max for prolonged use. You need a NEMA 14-50 at the least to make use of the charger's full capability.

Second thought. Is DCFC at 10kw worth that much trouble?

-TL

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Second thought. Is DCFC at 10kw worth that much trouble?
Not 10 kW. That Setec unit was popular in the LEAF world a few years ago when the onboard charger was limited to 3.3 kW. Back then it was worth it to get 3 times the charging speed via ChaDEmo.

But I could see the utility of a 20-25 kW unit in a home with multiple EVs. At that rate a full charge from empty is 2-3 hours, with an average closer to 1 hour. Multiple cars could then charge for an hour or two, drive around for a could of days locally, then quickly recharge.

This is the medium speed DCFC I always talk about in shared charging situations. Offers more flexible charging options and can service multiple vehicles.

ga2500ev
 

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The spec sheet says the maximum output is 20 amps. In my garage, even on 240 VAC, that would yield 400 V x 20 A = 8 kW max. I already get 7.6 kW into, and 7.2 kW out from my onboard charger. The Bolt gets its DC fast charge rates from high amperage, not high voltage.

Fincastle saw high of 56.3 kW.jpg
 

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The spec sheet says the maximum output is 20 amps. In my garage, even on 240 VAC, that would yield 400 V x 20 A = 8 kW max. I already get 7.6 kW into, and 7.2 kW out from my onboard charger. The Bolt gets its DC fast charge rates from high amperage, not high voltage.

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The input and output specs are quite confusing. I pulled up the 20 kW unit:

20kw CCS Combo Portable Charger - EV Fast Charger - ShenZhen SETEC Power Co., Ltd.

For single phase it says that the input current is max 40 A and that the output current is max 40 A too. While the unit does meet the nominal 20 kW charging speed for DCFC, which is current measured at 500V: 40A x 500V = 20kW, A 240V input at 40A maxes out at 9.6kW. The maximum amperage needs to be at least 80A input, which is 19.2 kW @ 240V to make any sense.

ga2500ev
 

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The input and output specs are quite confusing.

While the unit does meet the nominal 20 kW charging speed for DCFC, which is current measured at 500V: 40A x 500V = 20kW,
Technically, yes. But no EV that I know of charges to 500 volts. The Jaguar I-PACE, Audi e-tron, and upcoming Rivians use 108 cells in series for 450 volts max. The Porsche Taycan and several planned EVs charge to 800 volts max, so even at empty they are above 500 volts.
 

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Technically, yes. But no EV that I know of charges to 500 volts. The Jaguar I-PACE, Audi e-tron, and upcoming Rivians use 108 cells in series for 450 volts max. The Porsche Taycan and several planned EVs charge to 800 volts max, so even at empty they are above 500 volts.
It doesn't matter that EVs don't charge at 500V. That's the nomenclature that DCFC chargers use to describe their power output, since for some reason they don't use the constant value of amperage as their measure. A 100 kW DCFC is designed to deliver 200 amps at 500V. 200A * 500V = 100 kW.

That's why when cars like the Bolt says they charge at 50 kW, yet for almost all of any charging session the actual power is much less, it drives owners crazy. Common sense would dictate that a 50 kW station could charge a 50 kW EV at 50 kW. But it's impossible because a 50 kW station has that nameplate only at 500V. And as you correctly pointed out, no EV charges at 500V. A 50 kW station delivers up to 100 amps of current (again 100 amps * 500V = 50kW). A Bolt at 360V, which is about 50% SOC at 100 amps can only draw 36 kW.

The key is to watch the amps. You get the amps by dividing the nameplate wattage by 500V. So EA's 175 kW chargers can deliver 350 amps for example. The Bolt will charge at a maximum of 150 amps. That tops out right near that 50% state of charge. So the max speed is 150A * 360V = 54 kW, which is why GM states that the Bolt can charge at 50 kW. I wish all EVs and all chargers stated the amps they charge at, which is constant, instead of power in kW which changes from moment to moment.

My original point is that the Setec unit has a 20 kW nameplate and delivers the correct output current. However, it doesn't seem to take in enough power at 240 V in order to deliver that output current for the nominal 20 kW. 240V * 40A is only 9.6 kW. No matter how you chop it up, if the input is limited to 9.6 kW, then I cannot see how the Setec can deliver 40 amps at the voltages EVs typically charge on.

ga2500ev
 

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My original point is that the Setec unit has a 20 kW nameplate and delivers the correct output current. However, it doesn't seem to take in enough power at 240 V in order to deliver that output current for the nominal 20 kW. 240V * 40A is only 9.6 kW. No matter how you chop it up, if the input is limited to 9.6 kW, then I cannot see how the Setec can deliver 40 amps at the voltages EVs typically charge on.
Yup. Definitely deceptive. kW out can not be more than kW in. If it could, all our energy problems would be solved. :)
 

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That's the stuff of nightmares.

During my remodel, as we removed the old e-system, it was a running joke to shout across the house "Hey, you gotta see THIS one!" as we came across sketchy wiring. We lost track of how many scorch marks were in j-boxes. The "winner" was the re-routing of part of the the unused electric dryer's 30A circuit to use it for a microwave oven. The "handyman" pulled apart the conduit and swung one leg of the 240V over to the microwave. What he didn't pay attention to was that the washer and dryer circuit ALSO derived its ground connection through the 30A circuit's conduit. Yup...appliances with both electrical power and water present had no ground connections to them...for years.
Just last week I was running a small 1/4" water line to our new fridge in our finished basement. When I pulled the few ceiling tiles that I needed to take out, I noticed that one of the romex wires that were running through the basement ceiling had been cut and was just hanging about 6 inches away from the metal frame of the drop ceiling. I thought to myself, "there's no way that's live." I put my multimeter across it and, sure enough, saw 118 volts. After a few choice words, I pulled down all of the ceiling tiles and found about 4 more of the cut live wires, about 3 open wire-nut junctions not in boxes, about 3 junction boxes with no covers, and a few other odds and ends and strange wiring situations. I'll do plumbing all day long, but I don't mess with electricity so I called an electrician to fix all the issues and also rip out some old dead light fixtures that were used in the basement before it was finished.

Apparently one of the previous owners had a handyman install the drop ceiling and he must have also run the electrical as well. There were quite a few things that the electrician told me were classic "handyman specials". I also had the guy walk through the attic to make sure there weren't any surprises there, which thankfully there weren't. Looks like the guy who did the drop ceiling was the only one who did sub-par work.
 

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Just last week I was running a small 1/4" water line to our new fridge in our finished basement. When I pulled the few ceiling tiles that I needed to take out, I noticed that one of the romex wires that were running through the basement ceiling had been cut and was just hanging about 6 inches away from the metal frame of the drop ceiling. I thought to myself, "there's no way that's live." I put my multimeter across it and, sure enough, saw 118 volts. After a few choice words, I pulled down all of the ceiling tiles and found about 4 more of the cut live wires, about 3 open wire-nut junctions not in boxes, about 3 junction boxes with no covers, and a few other odds and ends and strange wiring situations. I'll do plumbing all day long, but I don't mess with electricity so I called an electrician to fix all the issues and also rip out some old dead light fixtures that were used in the basement before it was finished.

Apparently one of the previous owners had a handyman install the drop ceiling and he must have also run the electrical as well. There were quite a few things that the electrician told me were classic "handyman specials". I also had the guy walk through the attic to make sure there weren't any surprises there, which thankfully there weren't. Looks like the guy who did the drop ceiling was the only one who did sub-par work.
I'll say it again: NEVER allow a "handyman" to do electrical work...EVER! Bad wiring (I found plenty during a remodel) can KILL.

Hire a licensed and bonded electrician.
 

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My original point is that the Setec unit has a 20 kW nameplate and delivers the correct output current. However, it doesn't seem to take in enough power at 240 V in order to deliver that output current for the nominal 20 kW. 240V * 40A is only 9.6 kW. No matter how you chop it up, if the input is limited to 9.6 kW, then I cannot see how the Setec can deliver 40 amps at the voltages EVs typically charge on.
Note that this unit advertises both three phase and single phase. For a single phase voltage of 300V at 40A, then I'd agree. I think the actual output is 18kW given that it advertises up to [email protected] DC output.

It doesn't state what the current for the three phase is, but since it says 380V, then I'd suspect that it's 50A. If it was only 40A, then that would only be an output of 15.2kW, which seems a bit too far off. Three phase [email protected] service is pretty common in European residences, so I'd imagine that they are more targeting that market.
 

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TT-30 (120V 30A) can only deliver 120 * 30=3.6kW. In actual use it is probably 3kW max for prolonged use. You need a NEMA 14-50 at the least to make use of the charger's full capability.

Second thought. Is DCFC at 10kw worth that much trouble?
If you had to get the 3kW out of a TT-30 receptacle with a Bolt for whatever reason, e.g. road tripping and charging at campsites, it's better than the alternative of around 1.2kW.

It's also neat in general being able to charge a little faster than you could normally charge with the EVSE at home or to be able to take funny voltages, but not sure if the ~20% faster charging is really worth it for the price.
 

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I see the point. You will need to go DCFC for that.

You properly have checked into a RV park for the night. The difference between 3kw and 1.2kw in 10 hours is 18kwh, or 70 miles ish. That makes difference.

-TL

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Second second thought. That unit costs $2500, weighs about 45lb, and comes from China. No thank you! The day I carry that thing around will be the day where Satan lives has frozen over several times.

-TL

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But I could see the utility of a 20-25 kW unit in a home with multiple EVs. At that rate a full charge from empty is 2-3 hours, with an average closer to 1 hour.
I'd rather simultaneously charge multiple EVs slowly than have to go out and juggle fast charge connections every few hours when the occasion arises where you need to charge more than one of the cars overnight.
 

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I'd rather simultaneously charge multiple EVs slowly than have to go out and juggle fast charge connections every few hours when the occasion arises where you need to charge more than one of the cars overnight.
Right now I have a BEV and a PHEV. The PHEV needs to be charged every day. The BEV is charged twice a week. When the PHEV is replaced with a 200+ mile BEV, it too will be charged twice a week.

All else being equal, I would prefer to charge one EV quickly to charging multiple simultaneously but slower. We just alternate who charges which night. BUT on the occasion that we have a lot of driving in a single day, being able to quickly refill at home would be nice.
 

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I'd rather simultaneously charge multiple EVs slowly than have to go out and juggle fast charge connections every few hours when the occasion arises where you need to charge more than one of the cars overnight.
I'm obviously not in that situation yet, so I'm unsure as to how it may actually play out. But it just seems that the frequency of having to juggle multiple EVs charging all at the same time would be small.

I have a low range EV: a FIAT 500e. So I'm ABC: Always Be Charging. Does that behavior translate to longer range EVs like the Bolt? With my pre-Corona commuter round trip I likely could go a full week in a Bolt without having to charge in a normal week. Given that, and a charging station that can charge from 0 to 80% in 2-3 hours, would the ABC rules really still apply?

In any case, having a backup charger, like maybe the OEM charger @ 240V, might make sense too.

ga2500ev
 
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