Dual TT-30 to 14-50 Charging

[Supratachophobia]

Do you know if the truck will accept an adapted TT-30 >> 14-50? I ask because I tried this with my Model S and it refused to charge - possibly because it saw 120v on what it thought was going to be a 240v connection. I charged fine on a TT-30 >> 5-15 adapter, however.

Car doesn't care about voltage, only amps. The Tesla mobile charger has an operating range between 90-250 volts I think. For a tt adapter to work, you need to make sure it's wired right. And I use a 14-30 adapter on my mobile connector so that the car makes sure not to pull more amps than a tt-30 can support.

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[beatle]

You shouldn't use a 5-15 adapter for TT-30. While 5-15 is a 120V plug, it maxes out at 15A. You want a TT-30 to 14-50 that's meant for EV charging specifically. If you get one designed for EV charging it'll work as expected if you limit your charging to 24A (80% of 30A).

I charged at 12A with the adapter.

 

[beatle]

Car doesn't care about voltage, only amps. The Tesla mobile charger has an operating range between 90-250 volts I think. For a tt adapter to work, you need to make sure it's wired right. And I use a 14-30 adapter on my mobile connector so that the car makes sure not to pull more amps than a tt-30 can support.

Yes, I know the UMC is auto-ranging. Does your TT-30 adapter split the hot into both hot legs of the 14-30? The car or UMC may have otherwise been confused, only seeing voltage on one side, and thinking there was a problem.

 

[SPITmadFIRE]

I charged at 12A with the adapter.

You're getting half the speed you could by using the 5-15. You can charge at 24A with the 14-50 adaptor.

What we really need is a TT-30 directly to the EVSE adaptor like Tesla portable chargers have. Then there'd be no fussing around with changing amperage in the vehicle or getting the right EV rated jumpers.

 

[beatle]

I didn't plan to charge at all while at the campsite. They provided the use of an adapter so 12A was better than nothing at all.

Gen2 Tesla UMC has a 3rd party TT-30 adapter available:
https://www.evseadapters.com/products/tt-30-adapter-for-tesla-model-s-x-3-gen-2/

Not sure why Tesla doesn't offer a TT-30 adapter themselves as they have dongles for several other receptacle types.

 

[SwampNut]

Apparently electricity and math are super hard, there's a lot of misunderstanding in this thread. But this...

I'm disappointed in your math, and I think your math ancestors are too.

30 seconds earlier and you would have owed me a new keyboard. Finished my coffee just in time.

 

[Supratachophobia]

Yes, I know the UMC is auto-ranging. Does your TT-30 adapter split the hot into both hot legs of the 14-30? The car or UMC may have otherwise been confused, only seeing voltage on one side, and thinking there was a problem.

Just one leg of the 14-30 is used. It doesn't care. What I don't know is if it needs both ground and neutral. I wired up both when I made my adapter.

 

[pmbassett]

Do you know if the truck will accept an adapted TT-30 >> 14-50? I ask because I tried this with my Model S and it refused to charge - possibly because it saw 120v on what it thought was going to be a 240v connection. I charged fine on a TT-30 >> 5-15 adapter, however.

You were probably using a TT-30 to 14-50 adapter for RVs. These are wired differently in which it puts the hot wire onto both hot pins of the 14-50 and the neutral to neutral, so the UMC sees 0V across the hot pins and throws an error. This works fine for RV's because they use the two hot wires independently to drive 120v circuitry.

When wiring it for 120V EV charging you want to connect the neutral to the second hot pin so that the UMC sees 120v across the hot pins and adjusts accordingly, since NEMA is both 120v and 240v.

 

[FooF]

This one worked for me
https://www.amazon.com/gp/product/B07XNSXWM4/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

[beatle]

You were probably using a TT-30 to 14-50 adapter for RVs. These are wired differently in which it puts the hot wire onto both hot pins of the 14-50 and the neutral to neutral, so the UMC sees 0V across the hot pins and throws an error. This works fine for RV's because they use the two hot wires independently to drive 120v circuitry.

When wiring it for 120V EV charging you want to connect the neutral to the second hot pin so that the UMC sees 120v across the hot pins and adjusts accordingly, since NEMA is both 120v and 240v.

Good info. The adapter that refused to charge was used by my family who had an RV, so this all makes sense.

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