[evtinker]

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.

 

[evtinker]

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.

 

[evtinker]

It is too bad that there was apparently never a J-1772 specification supporting charging from a 30 Amp 120 Volt source, though it is understandable that it was seen as something most users would never need. I suspect that most EV chargers like that of the Bolt have hardware that is technically capable of doing this, but without an appropriate specification there is no support for it. I believe someone mentioned there is an EV that can do this, but I have forgotten which one it was.