Ok, check out: http://modularevpower.com/
J1772 to Nema 14-50 adapter
Looks like I should be able to take a hot, a neutral and ground off the Nema 14-50 plug and connect that to my 120v Nema 5-15 charger to charge by scooter.
I have 2 of the http://modularevpower.com/ J1772 to NEMA 14-50 adpaters that are rated up to 50 Amps. Got prompt delivery, high quality units and both work flawlessly. No hassles.
The J1772 standard does not have a neutral connection:
The round 43 mm diameter connector has five pins, with 3 different pin sizes
AC Line 1 and AC Line 2 - have same size power pins
Proximity Detection and Control Pilot - have same size pin
Proximity Detection - Prevents movement of the car while connected to the charger.
Control Pilot - Communication line used to coordinate charging level between the car and the charger as well as other information.
120V J1772 will have line conected to one of AC Line 1 pin and AC Line 2 pin and Neutral to the other for a 120V J1772 EVSE.
240V J1772 will have line 1 conected to one of AC Line 1 pin and AC Line 2 pin and Line 2 to the other for a 240V J1772 EVSE. There is no Neutral, so you CANNOT get 120V from a 240V J1772. Even if you do somnething dangerous, like use ground instead of neutral to get 120V, it won't work because the J1772 has a GFI that requires all the current on AC Line 1 to return through AC Line 2.
You also cannot get 120V from a 240V J1772 to NEMA 14-50 adapter or 240V Avcon to NEMA 14-50 adapter for the reasons above.
Also note that there is a grant in California to upgrade many of the Avcon stations to J1772. So it's best to get the Avcon station upgraded to J1772 and put a J1772 socket on your vehicle (or use a J1772 adapter if your vehicle needs that.) J1772 charging stations already far outnumber Avcons and the existing Avcons will likely be upgraded to J1772 in the coming year or so. The Avcon stations will not be maintained. If there's an Avcon you need to use and you have an Avcon adapter already or don't mind spending the money for an Avcon adpater that will be useless in a couple years, then you might get an Avcon adapter. You'll definitely want a J1772 connector (assuming you can deal with the J1772 being 120V or 240V, but not both from the same charging station.)
Thanks for the clarification. Do you know whether the J1772 station is looking for good power factor from the load? The reason I ask is that I want to help design an inexpensive high current version of the "Freddy" charger, and I expect this design will be seen as a poor power factor load.