In preparation for our first cross-country Model S camping trip, I was about to build a homemade NEMA 14-50 to TT-30 adapter, when I found the 'NEMA 14-50R to TT-30P' product that's apparently Tesla-compatible. I found it at EVSEadapters.com and was surprised to also find it at homedepot.com. Has anyone used this? Does it signal the proper amperage to the Tesla? With the homemade adapters, I understand you have to be very careful to first dial down to 24A before plugging in to avoid blowing a circuit or starting a fire since the Tesla will try to draw 40A. I don't see anything in the product description about this and I'd prefer not to experiment with it.