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Miles/charge time?

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Some charge questions:
- Is charge time linear regardless of charge state?
- I came up with 4 miles per hour of charge at 110V & 15A....sound right?
- How about at 230V and 30A?
Sorry if this has been covered, I searched but couldn't find it.
 
Some more napkin calculations to cross reference against yours, assuming current draw is limited to 80% of breaker capacity:

NEMA5-15 120V@12A=1.4kW... ~48 hour full charge... ~220 mile range / ~48 hours = ~4MPH.
NEMA6-30 240V@24A=5.7kW... ~10 hour full charge... ~220 mile range / ~10 hours = ~22MPH

Tesla chart:
Universal Adapters - Available in North America Only (charging) Tesla Motors
universal_chargetimes.gif
 
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Tom's blog post about the subject is pretty comprehensive:
Tesla Roadster Charging Rates and Efficiency - Tom Saxton's Blog

Some more napkin calculations to cross reference against yours:

NEMA5-15 120V@15A=1.8kW... ~48 hour full charge... ~220 mile range / ~48 hours = ~4MPH.
NEMA6-30 240V@30A=7.2kW... ~10 hour full charge... ~220 mile range / ~10 hours = ~22MPH

Tesla chart:
Universal Adapters - Available in North America Only (charging) Tesla Motors
universal_chargetimes.gif

Thanks! TS's blog has some interesting stats and shows that it's a moving target. The Adapter Charge Times chart answers the M/hr. question for a full charge.
 
Some more napkin calculations to cross reference against yours:

NEMA5-15 120V@15A=1.8kW... ~48 hour full charge... ~220 mile range / ~48 hours = ~4MPH.
NEMA6-30 240V@30A=7.2kW... ~10 hour full charge... ~220 mile range / ~10 hours = ~22MPH

Tesla chart:
Universal Adapters - Available in North America Only (charging) Tesla Motors

Actually looking at the chart, it is breaker rating, not actual current draw, so this is more correct:

NEMA5-15 120V@12A=1.4kW... ~48 hour full charge... ~220 mile range / ~48 hours = ~4MPH.
NEMA6-30 240V@24A=5.7kW... ~10 hour full charge... ~220 mile range / ~10 hours = ~22MPH
 
What about 30A RV plugs (30A @ 120v - TT30R)? If I remember correctly the roadster can only draw 15A @ 120V. I wonder if it is because that is the maximum it can draw at 120v or is it only limited by the UMC. 30A (120v) plugs are quite common in parks and it would a waste to only pull 15A. Charging a completely depleted battery would take 13h less if it could pull 24A (80% of 30A) instead of 15A.
 
Good question. I don't know the answer, although we had some discussion of TT-30 before:
Campground charging
Campground charging
Charging the Roadster

Apparently, if you use the MC120, I don't think there is a pilot signal, so the Roadster isn't willing to go higher than 15amps.

NEMA14-50: How much current can you pull?
...There is nothing available to the owner to go higher than the pilot signal from the connector. The car defaults to 12 amps and allows an override to 15 amps (by selecting 16 amps) when there is no pilot signal as with the MC120...
I recall at some point there was some discussion of trying to create a TT-30 plug with the diode or resistor in the twist lock that would convince a UMC or RFMC to send a 24amp pilot signal to the Roadster. I don't know if anyone ever made one of those, or if it would actually work to do 120V@24A.

RV supply places make TT-30 to NEMA14-50 adapter boxes. You might be able to re-wire one, and plug a MC240/UMC/RFMC into it to get 120V@24A. (Has anyone tried that?)
Amazon.com: GenTran 10/3 30 Amp TT-30 RV Plug to 50 Amp 125/250 Volt NEMA 1450 Receptacle Generator Adapter RJBATT30-1450R: Patio, Lawn Garden
31UpePNjh8L._SS500_.jpg
 
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NEC 625 only makes an exception for "125 volt, single phase, 15 or 20 amperes". The 30 amp will require the same kind of signaling as any 240V source. This requirement will apply to J1772 equipped vehicles too (which means the 120V cord in the Leaf and Volt won't be able to use the 30 amps either).