Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.

UMC waterproof?

is the regular UMC waterproof? i am charging to a 110V cable at my parents house, and car has to sit outdoors and its scheduled to rain all weekend. the end that will connect to the car can be subjected to water i believe, like in superchargers, but can that middle Tesla box thing, can that thing be subjected to rain? i will have it attached to an extension cord, and the the charger end will be indoors inside a garage. so only the middle tesla black box and the end that attaches to the tesla will be outdoors.

It will work, but you should keep the wall adapter portion and status display under the car so they will not be in direct contact with rain. You don't want any water causing an electrical short. You may want to get a 12 AWG cable to connect to the 120 V adapter/house outlet, or use electrical tape to seal the adapter that plugs in to the wall outlet.

The connector to the car's charge port should be fine even if it's exposed to rain. When done charging, store the cable in the trunk.
There have been many previous threads on this subject and the general consensus is that you can safely charge outside so long as the box is not in standing water. I have seen many HPWC boxes mounted outdoors where they are exposed to all kinds of weather and those seem much more vulnerable than the UMC box. The part that you'd want to be very careful with is the actual plug end, especially with 14-50 connections.
Flasher, is the box itself equipped with GFCI? That would ensure that the worst case is not so terrible. I'd assume it must be, but I don't actually know.

Yes, NEC art 625 requires the 30 mA GFI protection to be a part of the EVSE, and if cord-and-plug connected the unprotected part is limited to 12 inches or less. That said, the "north end" of the UMC is unprotected (the connection to the adapter and outlet).
The UMC Users Guide is ambiguous. Some of the warnings say you shouldn't let it get wet, but one talks about a precaution for use in the rain:

10-28-2015 9-19-40 AM.jpg
10-28-2015 9-19-18 AM.jpg
10-28-2015 9-18-22 AM.jpg