Direct Charging v Juicebox

[Rocky_H]

I simply bought a dryer buddy for 150$, plugged in the 10-30 to the wall, the dryer into the 10-30 port and the M3 into the 14-50 socket on the dryer buddy and it charges fine.

And yet, the TMC with that plug seems to only draw the 24A one would expect. It's not throttled by changing the max charging rate either?

Could it be that the UMC is more intelligent than we think?

Something is not adding up there at all. I think you are mixing up the outlet names. Is your Dryer Buddy actually a 10-30 and 14-30? The Tesla charge cable uses a resistor inside the particular adapter it has attached to tell it how many amps to use. If you are using a 14-30 plug, then the car will know to only use 24A. If you are using a Tesla 14-50 plug, as you said, it would have no way at all to know that it should only use 24A.

 

[tivoboy]

Something is not adding up there at all. I think you are mixing up the outlet names. Is your Dryer Buddy actually a 10-30 and 14-30? The Tesla charge cable uses a resistor inside the particular adapter it has attached to tell it how many amps to use. If you are using a 14-30 plug, then the car will know to only use 24A. If you are using a Tesla 14-50 plug, as you said, it would have no way at all to know that it should only use 24A.

The DB is 10-30 on the cable end, with a 10-30 socket (for the dyer) and the EVSE 14-50 socket which is monitored but not switched (which I have the UMC2 14-50 adaptor connected to).

Now in that connection, the car is only pulling 24A, which is reflected on the DB display (nice multi-color display) and in the car.

Now that I look at the car to confirm, the car DOES seem to think there is "charging" at this location. Maybe is it caching a charging profile? I seem to recall some discussion of that.

Could the car have 'recalled' the charging history having originally used a 10-30 adaptor straight in the wall and is set for this 'location' to only want to charge o 24A unless adjusted even though the same UMB2 is now has a 14-50 connector on the end?

 

[Rocky_H]

Now that I look at the car to confirm, the car DOES seem to think there is "charging" at this location. Maybe is it caching a charging profile? I seem to recall some discussion of that.

Could the car have 'recalled' the charging history having originally used a 10-30 adaptor straight in the wall and is set for this 'location' to only want to charge o 24A unless adjusted even though the same UMB2 is now has a 14-50 connector on the end?

Yes, THAT makes sense. Once you have set a non-default value at the car lower than maximum at a specific location, it memorizes that amp value for the charging profile associated with that location. That explains it. If you were to turn it down to 23 or 22, it would re-memorize it and always use that value every night.

 

[tga]

To extend that to another area and switch to a 14-50 or 14-30 it would need to have two hots a neutral and a ground (often times the wiring has these, but people just installed the old receptacle type because that is what folks dyers needed)

If a 10-30 is correctly wired with Romex, then it will have all 4 (hot/hot/neutral/ground) using 10/3. Wiring a 10- series outlet with /2 (white/black/ground) is a violation, because you are using the bare ground wire as a current carrying conductor (neutral).

 

[brucet999]

If a 10-30 is correctly wired with Romex, then it will have all 4 (hot/hot/neutral/ground) using 10/3. Wiring a 10- series outlet with /2 (white/black/ground) is a violation, because you are using the bare ground wire as a current carrying conductor (neutral).

The presence of a ground wire in 10/3 Romex is of no use when connected to a 10-30 outlet because the appliances have no connection to ground. NEMA 10-30 outlets were often wired with three wires in conduit where the conduit itself served as a ground path, but, again the appliance had no ground connection, so it didn't matter.

 

[tga]

The presence of a ground wire in 10/3 Romex is of no use when connected to a 10-30 outlet because the appliances have no connection to ground. NEMA 10-30 outlets were often wired with three wires in conduit where the conduit itself served as a ground path, but, again the appliance had no ground connection, so it didn't matter.

Right. I'm just saying that if it's wired with romex, there should already be a ground, so conversion from 10 series to 14 series would be trivial.

My 1972 house has a 10-30 dryer outlet and 10-50 range outlet. The dryer outlet is wired with 10/3 romex. The range is wired with 6/2 AL SEU (*blech*), which I'll convert to cu 6/3 romex during the kitchen remodel.

 

[PJFW8]

So I'm the new kid on the block and following this thread seems to be a bit confusing.
Here's my question:
I have a old unused Clothes Dryer outlet with a NEMA 10-30 socket that is being converted to a NEMA 14-50 socket. However we are not able to up the amps (because it requires changing the wires which is not economical). So although there will be a 14-50 socket we are left with 30 amps.

The question is which of the 3 methods below will provide the best output charging current for the M3-LR:
1. Use the TESLA provided cable plugged into the 14-50?
2. Install and use the TESLA Wall Connector (HPWC)?
3. Install and use a JuiceBox Pro40?

Do not convert to 14-50. Adapt to the 10-30. The Tesla adapter is $35. (By far the easiest and cheapest alternative.) This allows 24 amp charging and is safe. Or...Install a Tesla Wall connector. It is a good deal at $500. Run at least a 6 gauge copper wire in conduit and a 60 amp breaker. This will allow 48 amp charging. JuiceBox is good equipment, but provides no advantage unless you intend to charge other EVs. Your choice is based on the need for speed. I went with 48 amps because I needed to run a new circuit. No point pulling smaller wires!

 

[Reid]

So I'm the new kid on the block and following this thread seems to be a bit confusing.
Here's my question:
I have a old unused Clothes Dryer outlet with a NEMA 10-30 socket that is being converted to a NEMA 14-50 socket. However we are not able to up the amps (because it requires changing the wires which is not economical). So although there will be a 14-50 socket we are left with 30 amps.

Or you could have just bought the Tesla 10-30 adapter for $35...

 

[eprosenx]

The presence of a ground wire in 10/3 Romex is of no use when connected to a 10-30 outlet because the appliances have no connection to ground. NEMA 10-30 outlets were often wired with three wires in conduit where the conduit itself served as a ground path, but, again the appliance had no ground connection, so it didn't matter.

So yeah, I think if there is continuous metallic conduit back to the breaker panel that even if you had "hot hot neutral" conductors in a metallic conduit, then you are still allowed to use the conduit as a ground (though I think some folks frown on this).

 

[brucet999]

So yeah, I think if there is continuous metallic conduit back to the breaker panel that even if you had "hot hot neutral" conductors in a metallic conduit, then you are still allowed to use the conduit as a ground (though I think some folks frown on this).

Present day code in most places does not allow conduit as ground, but previously it was allowed. The thinking is that flex conduit-to-box connections and thin wall conduit couplings may lose their connectivity over time through corrosion or coming loose.

 

[eprosenx]

Present day code in most places does not allow conduit as ground, but previously it was allowed. The thinking is that flex conduit-to-box connections and thin wall conduit couplings may lose their connectivity over time through corrosion or coming loose.

Hrm, I don't think this is true.

Please see 250.118.
NFPA 70®: National Electrical Code®

Rigid, IMC, EMT and flex are all allowed to be used as the grounding conductor in 2017 NEC. Flex does have limitations of circuit size (no larger than 20 amps, length limits, etc...). Of course your jurisdiction may have not adopted the NEC verbatim so YMMV.