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Discussion Starter · #2 ·
Parts required

-tt-30 extension cord
-hospital grade outlet
-5000w power converter transformer (like a EU to US converter)
-3m 5200 adhesive sealant
-bolts, drills, files, time,
-strain relief, hose clamp for extra security
 

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2020 Chevy Bolt and all Tesla models owned by me and my family
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This science experiment is nice.
But have you considered how much losses are getting just to run EV at 240V.
I don't see any benefit in this.
You can have more efficient way charging at 120V and using EVSE that can provide 16A and L1 power supply attached.
But i do like your work.
 

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That contraption steps up the TT-30 voltage to 240v. At 240v, the Bolt will draw more current than the circuit is rated for. The comment in the video pretty much sums up the result of this experiment: "this is on a 20 amp circuit, so just testing. It's probably blow that breaker here in a second..."
 

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That contraption steps up the TT-30 voltage to 240v. At 240v, the Bolt will draw more current than the circuit is rated for. The comment in the video pretty much sums up the result of this experiment: "this is on a 20 amp circuit, so just testing. It's probably blow that breaker here in a second..."
I assume you are referring to my comment?

I get that the solution is 240V, but the comment I responded to was specifically 120V 16A EVSE, which would do nothing for a Bolt because it limits 120V to 12A.
 

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That contraption steps up the TT-30 voltage to 240v. At 240v, the Bolt will draw more current than the circuit is rated for. The comment in the video pretty much sums up the result of this experiment: "this is on a 20 amp circuit, so just testing. It's probably blow that breaker here in a second..."
Well, a TT30 circuit is normally rated for 30A. So the stepped-up output should be rated for 240V 15A (ignoring transformer loss). So the OEM EVSE (12A 240V) meets the 80% rule. (Whether it's worth lugging this box around is another question!)
 

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Well, a TT30 circuit is normally rated for 30A. So the stepped-up output should be rated for 240V 15A (ignoring transformer loss). So the OEM EVSE (12A 240V) meets the 80% rule. (Whether it's worth lugging this box around is another question!)
If the guy in the video is using the level 1 EVSE but at the stepped-up 240v, then it might work. The dual-level EVSE currently available will draw 32 amps at 240v, which will pop the breaker.
 

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I'm sorry I have completely missed that Bolt cannot take more than 12A at 120V L1 even EVSE aftermarket solutions are available.
How you test to see if it takes more than 12A at 240V input on single phase.
 

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Single to split phase transformer style would be ideal. And EVSE where you can adjust current output.
There are 5 kWh aftermarket solutions available for not much money. But use will be limited to high output 120 Single phase supply. I do use something like this with my mobile solar system if I need quicker charging. With solar power losses are irrelevant it is free anyway.
 

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I'm sorry I have completely missed that Bolt cannot take more than 12A at 120V L1 even EVSE aftermarket solutions are available.
How you test to see if it takes more than 12A at 240V input on single phase.
Just try it. Plug a 16A single phase EVSE in to a Bolt, and go to the infotainment screen toggle that allows you to set 8 or 12A. Done, 12A is max!

There are not many single phase EVSE with >12A. Tesla UMC, and maybe Clipper Creek? On the EV side, Tesla and maybe Rivian can select higher single phase charging currents.
 

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Discussion Starter · #13 ·
On 120V, Bolt limits charging to 12A, regardless of what the EVSE is capable of supplying.
correct, which is the reason for this adapter


That contraption steps up the TT-30 voltage to 240v. At 240v, the Bolt will draw more current than the circuit is rated for. The comment in the video pretty much sums up the result of this experiment: "this is on a 20 amp circuit, so just testing. It's probably blow that breaker here in a second..."
Normally that outlet would be on a 30a breaker which at 24a which is what this device will pull would be fine.

I'm sorry I have completely missed that Bolt cannot take more than 12A at 120V L1 even EVSE aftermarket solutions are available.
How you test to see if it takes more than 12A at 240V input on single phase.
If you want to test, on a 40a evse, route neutral to where l2 usually is. And set the evse to whatever amperage. The bolt refuses to take more than 12a

Single to split phase transformer style would be ideal. And EVSE where you can adjust current output.
There are 5 kWh aftermarket solutions available for not much money. But use will be limited to high output 120 Single phase supply. I do use something like this with my mobile solar system if I need quicker charging. With solar power losses are irrelevant it is free anyway.
This is a phase flipping transformer. It’s a 1:1 with two leads tied. Basically flipping the pahse and making split phase.
 

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What is the point of this? The OEM charger will run on 240 and all you need is a converter for the plug and a 240 outlet.
The point is there isn’t access to a 240 Volt outlet, only an existing 120 Volt 30 Amp TT-30 outlet. Without the transformer, the Bolt can only charge at 120 Volts at 12 Amps, 1440 Watts even though the TT-30 outlet is actually capable of delivering 2880 Watts. By stepping up to 240 Volts with the transformer the charge rate can be doubled. This does kind of come under the category of an interesting solution in search of a problem. I suppose if one had routine access to a TT-30 outlet and no chance of upgrading it to 240 Volts, then this might be helpful. I do find it an interesting project. I suppose it one routinely car camped in older campgrounds with only TT-30 outlets it could be handy.
 

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The point is there isn’t access to a 240 Volt outlet, only an existing 120 Volt 30 Amp TT-30 outlet. Without the transformer, the Bolt can only charge at 120 Volts at 12 Amps, 1440 Watts even though the TT-30 outlet is actually capable of delivering 2880 Watts. By stepping up to 240 Volts with the transformer the charge rate can be doubled. This does kind of come under the category of an interesting solution in search of a problem. I suppose if one had routine access to a TT-30 outlet and no chance of upgrading it to 240 Volts, then this might be helpful. I do find it an interesting project. I suppose it one routinely car camped in older campgrounds with only TT-30 outlets it could be handy.
why not just convert the outlet to a 30 amp 240 NEMA 10 - 30 and the breaker to 240? Just use the 120 neutral for a 240 hot.
 

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Discussion Starter · #17 ·
The point is there isn’t access to a 240 Volt outlet, only an existing 120 Volt 30 Amp TT-30 outlet. Without the transformer, the Bolt can only charge at 120 Volts at 12 Amps, 1440 Watts even though the TT-30 outlet is actually capable of delivering 2880 Watts. By stepping up to 240 Volts with the transformer the charge rate can be doubled. This does kind of come under the category of an interesting solution in search of a problem. I suppose if one had routine access to a TT-30 outlet and no chance of upgrading it to 240 Volts, then this might be helpful. I do find it an interesting project. I suppose it one routinely car camped in older campgrounds with only TT-30 outlets it could be handy.
Yes, it has happened to me a few times that a tt-30 was the highest wattage outlet available.

but I will actually probably mostly be using this at home odly,

see I am on solar and for some reason the car refuses to charge on my 240v dirty power signal I suspect. But it will work on 120v because that inverter has so many loads on it that the signal is cleaned up enough.

so I will install a tt-30 and double my home charge rate. Until I can solve the 240v problem and charge at full 33a 240. That will require a new control board for my inverters which I am currently helping with the development of. These are old sw5548 trace units. Upgrading would be dificult and expensive. Also the car is the only thing complaining and they work. So… maybe a new car is also an option lol.

anyway. I will also take it on road trips. I have encountered tt-30 as the only option at some destinations or charging stops sometimes. So two birds with one stone. Traveling adapter and home bandaid.
 

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why not just convert the outlet to a 30 amp 240 NEMA 10 - 30 and the breaker to 240? Just use the 120 neutral for a 240 hot.
Just base this on the assumption that no changes to the outlet or breaker are permitted, say a rental property or a campground that doesn't have 240 Volt outlets. The only option is to use the existing TT-30.
 

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Don't encounter TT-30 enough to justify the cost, but I do see step-up transformers on Amazon for $150-200. Most aren't too big...

Combining two separate 120V circuits into a 240V circuit is probably a more common scenario. Unfortunately you do have GFCI to worry about these days.
 

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Discussion Starter · #20 ·
Don't encounter TT-30 enough to justify the cost, but I do see step-up transformers on Amazon for $150-200. Most aren't too big...

Combining two separate 120V circuits into a 240V circuit is probably a more common scenario. Unfortunately you do have GFCI to worry about these days.
Yes, I also cary a combiner and extension cord
 
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