New UMC

[Cosmacelf]

Anyhoo, I'm glad to see Tesla finally coming out with a redesigned UMC. The original UMCs had a bunch of glaring deficiencies. The adapters never mated with the UMC very well, they were right beside the electrical socket, allowing heat to hit the adapter from two sides, they never supported a broad enough range of adapters, and they had the inherent problem of supporting 40A charging on outlets that sometimes had 40A breakers on them (both 6-50 and 14-50 receptacles in the wild could have lower rated rated breakers).

This new UMC appears to fix all these problems.

The only downside is that you can now only charge at maximum 32A instead of 40A. This is not a big downside in my books.

Speculation here: I presume this new UMC will start to be given out to new Model S and X cars and will completely replace the existing, original design UMC...

 

[stopcrazypp]

Maybe because the old UMC did support 40A?

Here, 32 amps for standard and 40 for LR:

Press Kit | Tesla Canada

What I mean is if they are not referring to the capability of the onboard charger of the respective cars in that spec, then why would they say 32A for SR and 40A for LR instead of 40A (or 32A) for both?

The LR is currently shipping with the new UMC which is only 32A capable. If the car is capable of 48A instead of 40A, then why would it say 40A? Where does the 40A come from?

Side Note: I'm talking about the software limited speed of the onboard charger (I know Tesla might put a 40A or 48A charger in the car and software limit it depending on which version you buy).

 

[03DSG]

Confusing for sure. Tesla needs to clarify this. Many are already doing electrical upgrades to be ready, including me.

 

[stopcrazypp]

Confusing for sure. Tesla needs to clarify this. Many are already doing electrical upgrades to be ready, including me.

But my point before is that all the 48A talk was just rumor from before the Tesla handover event. The only official information we have is 32A for SR and 40A for LR. Tesla has never mentioned 48A.

 

[03DSG]

You are right. This is all we have:

Tesla Model 3 To Come With 48-Amp Onboard Charger

This one is charging at 48 amps:

 

[stopcrazypp]

You are right. This is all we have:

Tesla Model 3 To Come With 48-Amp Onboard Charger

This one is charging at 48 amps:

View attachment 245391

I neglected to ask in the first round, but do you have the source of the photo? It may be possible to determine if the car is an RC or actually a production car.

 

[Zoomit]

I was just looking at the link and it appears that the charging speeds picture has a wrong link. I fixed the link and it shows the following picture:

https://shop.tesla.com/content/dam/tesla/CAR_ACCESSORIES/MODEL_3/CHARGING_ADAPTERS/Model3_NEMA.png

Outstanding find. By making a few reasonable assumptions, we can use this to predict driving efficiency and EPA range.

However, I've done the math and the efficiencies work out higher than I expected. I plotted them and the 6-20 is the most efficient on a mphc/kW basis. It charges at 240A*16A = 3.84kW and (per the table) yields 16 mphc. That equals 240 Wh/mi before charging losses. If we assume the charger is 92% efficient, this yields 221 Wh/mi. If we assume this charge is for a Model 3 SR with a 52.7 kWh usable battery, we can convert that to miles of range. It equals 239 miles. Doing the same for the 3 LR, it equals 344 miles. But I don't believe these numbers.

I think the 16 miles listed is somewhere actually just above 15.5 mphc and they rounded up. Reruning the calculations assuming 15.5 mphc, yields 231 miles range. Increasing the charger efficiency to 95% lowers this number to 224 miles for the SR and 333 miles for the LR.

I suspect the Model 3 data for this table is from an SR that gets at least 224 miles range or an LR that gets at least 333 miles range.

 

[wws]

The one adapter they forgot is a TT-30. Fortunately it should be easy to make ones own, combined with their 14-30 pigtail.

 

[Enginerd]

I was late to find this thread, but I did find it right before starting to build my collection of (the wrong old) UMC adapters. Thanks again TMC!

 

[boaterva]

I recommend these adapters when not getting the Tesla ones, especially the TT-30. And for that one, the cabled version is better, less drag on the socket:

NEMA 14-50R to TT-30P Adapter for EV Charging at Campgrounds

 

[ccutrer]

I recommend these adapters when not getting the Tesla ones, especially the TT-30. And for that one, the cabled version is better, less drag on the socket:

NEMA 14-50R to TT-30P Adapter for EV Charging at Campgrounds

I think @wws' point is that with pigtail official UMC adapters, you may be able to cut off the male plug and put whatever plug you want onto it, and end up with a semi-official adapter, rather than two chained adapters. Assuming the resistor that tells the UMC which amperage to use isn't in the male plug that gets removed, I think this is brilliant. Makes it much easier for someone else to just plug in the one thing that fits, rather than having to puzzle out which combination of adapters might happen to work. And in the case of 240V <=> 120V franken-adapters (TT-30 to 14-30/14-50; 6-20 to 5-20), scary labeling that you shouldn't plug in normal things with the adapter, only cars. The downside is if you use (appropriate gauge) extension cords, you can't use a 14-50 least common denominator cord.

 

[Cosmacelf]

I think @wws' point is that with pigtail official UMC adapters, you may be able to cut off the male plug and put whatever plug you want onto it, and end up with a semi-official adapter, rather than two chained adapters. Assuming the resistor that tells the UMC which amperage to use isn't in the male plug that gets removed, I think this is brilliant. Makes it much easier for someone else to just plug in the one thing that fits, rather than having to puzzle out which combination of adapters might happen to work. And in the case of 240V <=> 120V franken-adapters (TT-30 to 14-30/14-50; 6-20 to 5-20), scary labeling that you shouldn't plug in normal things with the adapter, only cars. The downside is if you use (appropriate gauge) extension cords, you can't use a 14-50 least common denominator cord.

Yes that makes sense. So to make a TT-30 adapter, just buy the new UMC 10-30 adapter, cut off the 10-30 end and wire in the TT-30 plug. The amperage resistor is almost certainly in the proprietary Tesla plug side so that should work.

I've ordered one of the those new adapters from the website and will take it apart when I get it to confirm.

The problem of potentially needing multiple extension cords remains, but for that problem, I like to use Quick Charge Power's service that will lengthen your UMC cable length from 20' to 50' or whatever you need.

 

[boaterva]

Yes that makes sense. So to make a TT-30 adapter, just buy the new UMC 10-30 adapter, cut off the 10-30 end and wire in the TT-30 plug. The amperage resistor is almost certainly in the proprietary Tesla plug side so that should work.

I've ordered one of the those new adapters from the website and will take it apart when I get it to confirm.

The problem of potentially needing multiple extension cords remains, but for that problem, I like to use Quick Charge Power's service that will lengthen your UMC cable length from 20' to 50' or whatever you need.

Gotcha... looking forward to hearing where the resistor is on the new series of adapters!

 

[ccutrer]

Yes that makes sense. So to make a TT-30 adapter, just buy the new UMC 10-30 adapter, cut off the 10-30 end and wire in the TT-30 plug. The amperage resistor is almost certainly in the proprietary Tesla plug side so that should work.

I've ordered one of the those new adapters from the website and will take it apart when I get it to confirm.

The problem of potentially needing multiple extension cords remains, but for that problem, I like to use Quick Charge Power's service that will lengthen your UMC cable length from 20' to 50' or whatever you need.

Ooh I didn't know about that service. I like that better than extension cords, because you can use the proper adapter for amperage limitations (my wife would never k is to dial it down if using a 14-50 least common denominator adapter). So hard to know, though. I charged two months ago off a 14-50 with a 50' 14-50 extension, plus the normal UMC. It was barely long enough. I'm not sure I'd like to normally carry a 70' UMC around though.

 

[Cosmacelf]

Ooh I didn't know about that service. I like that better than extension cords, because you can use the proper adapter for amperage limitations (my wife would never k is to dial it down if using a 14-50 least common denominator adapter). So hard to know, though. I charged two months ago off a 14-50 with a 50' 14-50 extension, plus the normal UMC. It was barely long enough. I'm not sure I'd like to normally carry a 70' UMC around though.

I know what you mean. I've charged at the limit of my bulky 30' 14-50 extension cord, and I know of a place that if I go there, I will need more than 50'. But more than 50' is a very rare occurrence.

The nice thing about the UMC lengthening is that the UMC cord is a lot lighter than a NEMA 14-50 extension cord (one less large conductor among other reasons). I can't imagine how heavy your 50' 14-50 extension cord is!

 

[boaterva]

I know what you mean. I've charged at the limit of my bulky 30' 14-50 extension cord, and I know of a place that if I go there, I will need more than 50'. But more than 50' is a very rare occurrence.

The nice thing about the UMC lengthening is that the UMC cord is a lot lighter than a NEMA 14-50 extension cord (one less large conductor among other reasons). I can't imagine how heavy your 50' 14-50 extension cord is!

Yeah, I bought a 20' foot one, thinking that and the UMC would handle most cases, and I can also handle dialing back the car to 24 Amps as needed with the other adapters. When we get my girlfriend the Model 3, we will have to perhaps be a little more 'automatic' in how charging works when away from destination chargers and SuC's!

 

[eladts]

Perhaps in the future third parties will modify the adapters to have longer pigtail. This way you can extend the new UMC without modifying the main unit and without using a heavy 14-50 extension cable and fraken-adapters.

 

[ccutrer]

Perhaps in the future third parties will modify the adapters to have longer pigtail. This way you can extend the new UMC without modifying the main unit and without using a heavy 14-50 extension cable and fraken-adapters.

Ideally you could get an extension for whatever the Tesla proprietary connection is between the pigtail adapter and the UMC body. That's probably a tall order, though, since presumably it's proprietary, and even if you're using cannibalized pigtails for one end, you'd need to produce your own connector to stand in for the UMC side. The closest I've seen is the JDapter Stub has a female Tesla connector that's presumably custom molded. And that is definitely not a cheap adapter for 2 ft. of extension!

 

[eladts]

Ideally you could get an extension for whatever the Tesla proprietary connection is between the pigtail adapter and the UMC body.

Yes, if someone can pull this off it would be ideal. Such cable will be much lighter than 14-50 extension for sure, because it needs to be rated for 40A and have only three conductors.

 

[FlatSix911]

Keep in mind that the actual charging rate is 80% of the Circuit Breaker rating ... i.e. the Nema 14-50 will charge at 40 amps.

I was just looking at the link and it appears that the charging speeds picture has a wrong link. I fixed the link and it shows the following picture:

https://shop.tesla.com/content/dam/tesla/CAR_ACCESSORIES/MODEL_3/CHARGING_ADAPTERS/Model3_NEMA.png