Inlaws just put a plug in their garage; they say it's on "at least" a 30 amp fuse, but don't know the plug type. Here's a pic. The online guides I've looked at are ambiguous (at least to my untrained eye). Is this a NEMA 6-30?
Looks like an L6-30 twist-lock connector. This has no neutral wire on it, so you can't convert to a 14-30, but you could convert this to a 10-30 receptacle and then use this adaptor on your UMC: Tesla Gear Shop NEMA 10-30
Awesome, thanks--totally missed the writing on the plug. That's the problem with posting from a phone!
Assuming that I first dial the amps down to 24, any issues with using this adapter? NEMA 14-50R to L6-30P Twist-Lock Adapter
That adapter should work just fine. Alternatively you could buy the version that converts to a 10-30, then buy/use Tesla's 10-30 adapter. That way you wouldn't have to dial down the amperage. Either way works.
I would strongly suggest you select the NEMA 10-30 option (4th one down on the link that you provided) instead of the 14-50 to eliminate any potential issues of forgetting to lower your amp adjustment to 24 amps and of course purchasing the necessary Tesla UMC 10-30 adapter. I am against "hanging" a 14-50 on many adapters as we saw a downright scary thread here recently. ah....Cos beat me to it !
I did a little image enhancement and 180˚ rotate. See below. I read this as a L6-50R. If that is correct, and it is fed by a 50 Amp breaker, all you need to buy or make is an L6-50P to 14-50R adapter in the same manner as folks make a 6-50 to 14-50 adapter for Tesla Charging. You may well be able to charge at 40 Amps!!! There is a lot of discussion at Tesla no longer selling NEMA 6-50 Adapter - Page 9 and other threads on doing this reasonably safely. Good Luck!
After the image enhancement, I read that it's a NEMA L6-30–R 30A. The L prefix denotes that it's a locking NEMA connector.
You are correct; it's an L6-30R. I got fooled by some artifacts. See enlargement below. In this case, to be safe, I recommend buying/making a L6-30P to 10-30R adapter, and use the Tesla Tesla Gear Shop NEMA 10-30 UMC Adapter. The L6-30P to 10-30R adapter will connect the ground in the L6-30P to the neutral in the 10-30, normally not recommended, but that is what Tesla is doing in the UMC adapter, anyway. Using a 30 Amp adapter means that the car will set the charging current correctly.
It even better, if they don't actually need the L6-30 for anything, just replace the outlet with a 10-30. Less fussing with adapters that way.
Thanks. I've ordered the 6-30 to 10-30 cable/adapter and the 10-30 adapter for the UMC. May propose replacing it with a 10-30R--that's a good suggestion, too.
Think having an electrician replace the faceplate to a 10-30 assuming that works Would be best. Good luck.
That is a code issue. 10-30's are not approved for new installs, and then you get into the whole ground/neutral question on a permanent outlet in the house. Even though it is a little "Rube Goldberg", I would stay with the 6-30 to 10-30 cable/adapter and the 10-30 adapter for the UMC.
Ah. I'm moving to a house that already has a 10-30. I bought the adapter for the UMC. Should I pay to have it replaced with a 14-50?
A 10-30 or 10-50 is grandfathered in, if it is already there, and not an issue for charging a Tesla. See details below. There are many who felt a "tickle" when touching an old dryer or range. This won't happen with a Tesla because the Tesla does not use 120 V connections with a 10-30. From NEMA 10 Connectors - Wikipedia: NEMA 10 devices are a curious throwback to an earlier time. They are classified as 125/250 V non-grounding (hot-hot-neutral), yet they are usually used in a manner that effectively grounds the appliance, though not in a manner consistent with most modern practice. As commonly used, 10–30 and 10–50 plugs have the frame of the appliance grounded through the neutral blade. This was a legal grounding method under the National Electrical Code for electric ranges and electric clothes dryers from the 1947 to the 1996 edition. Since North American dryers and ranges have certain parts (timers, lights, fans, etc.) that run on 120 V, this means that the wire used for grounding is also carrying current. Although this is contrary to modern grounding practice, such installations remain common in the United States and are relatively safe, because the larger conductors used are less likely to be broken than the smaller conductors used in ordinary appliance cords, and the current carried on the neutral conductor is small.