TT-30 RV park "30 amp service" adaptor

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http://cosmacelf.net/Home%20Made%20Adapters.pdf

TT-30 RV park "30 amp" service

Many RV suppliers sell an RV “50 AMP to 30 AMP” adapter cable. THESE WILL NOT WORK WITH THE TESLA as they are wired incorrectly for the TESLA. However we can use one of these adapter cables, cut off the NEMA 14-50 end (and throw it out) and make our own Tesla adapter.

So, as usual, buy a Camco® PowerGripTM Replacement Receptacle Female:

http://www.amazon.com/gp/product/B00192QB9M/ref=oh_details_o04_s02_i00?ie=UTF8&psc=1

And then a RV 30 AMP to 50 AMP adapter:

Camco 55185 RV Powergrip 30M/50F Amp 18" Dogbone Electrical Adapter with Handles 125Volts/3750Watts

http://www.amazon.com/gp/product/B000BUQOGI/ref=oh_details_o04_s00_i00?ie=UTF8&psc=1

Cut off the NEMA 14-50 part of the adapter. Carefully strip away the outer insulation trying to not also cut through the inner insulation of one of the wires, to expose the three wires.

Here’s where it gets a bit tricky. If you look at the FACE of a NEMA 14-50 RECEPTACLE, the bottom round prong should be connected to ground. For a 120V supply, Tesla wants the leftmost blade to be connected to the 120V hot, and the rightmost blade to be connected the 120V neutral (note this is opposite to what a typical household receptacle does).

The TT-30 PLUG has a round shaped ground prong. If you place that round ground prong on top, and have the PLUG facing you, the bottom left angled blade is the neutral (sometimes labeled W on the plug), and the bottom right angled blade is the 120V hot.

Connect the TT-30 round ground prong to the NEMA 14-50 round ground prong. Connect the TT-30 hot to the leftmost NEMA 14-50 blade when looking at the front of the NEMA 14-50 receptacle, assuming ground is at the bottom. Connect the TT-30 neutral to the rightmost NEMA 14-50 blade when looking at the front of the NEMA 14-50 receptacle, assuming ground is at the bottom. Leave the NEMA 14-50 neutral UNCONNECTED.

Label it with a reminder to set the Tesla car’s charging app to maximum 24 amps. If you have an RV you might also want to label the adapters as TESLA CHARGING ONLY, NO RV USE. Actually, this adapter should especially be labeled with that warning as both of these plugs/receptacles ARE used in RV parks and adapters that look just like this (but are wired differently) are used all the time in RV parks.
20A Maximum for 120V supplies

By the way, I’ve used this adapter a couple of times for charging my Tesla, and the maximum current the Tesla would pull from it is 20A, even though I had set it for 24A. It is likely that Tesla has a built in software limitation that if the source power is only 120V, it’ll only pull a maximum of 20A. This is unfortunate and I hope they fix this sometime, but it is hard to push for a fix since from their perspective, you are doing something completely unsupported anyways.
 
http://cosmacelf.net/Home%20Made%20Adapters.pdf


20A Maximum for 120V supplies:

By the way, I’ve used this adapter a couple of times for charging my Tesla, and the maximum current the Tesla would pull from it is 20A, even though I had set it for 24A. It is likely that Tesla has a built in software limitation that if the source power is only 120V, it’ll only pull a maximum of 20A. This is unfortunate and I hope they fix this sometime, but it is hard to push for a fix since from their perspective, you are doing something completely unsupported anyways.
 
Tony

Thanks for the info. I built the adapter today (the parts had arrived when I came home from gathering yesterday morning). Do you have any idea what the white powder is that is used as an insulator in that cable. This is the first cable I have cut into that used a powder insulator rather than paper.

Mike
 
Michael Bornstein said:
Tony

Thanks for the info. I built the adapter today (the parts had arrived when I came home from gathering yesterday morning). Do you have any idea what the white powder is that is used as an insulator in that cable. This is the first cable I have cut into that used a powder insulator rather than paper.

Mike

If there is a powder in a cable, its not an insulator; it's for flexibility.
 
I know this is an old thread, but it seems the most appropriate. I read here that people were thinking of various ways to use a TT-30 outlet, but I didn't see anyone reporting back about what they found when they tried it. Is there a way to get the maximum number of amps out of the 120 volt, 30 amp, TT-30 outlet. I understand that the maximum is 24 amps, but the RAV4-EV limits 120 volt charging to 20 amps. I have an adapter (which I haven't tried yet) that will adapt the 5-20 plug on the Jesla to the TT-30, which is supposed to charge at 16 amps. I was wondering if anyone was able to do better?

John
John Blair
 
jgblair said:
I know this is an old thread, but it seems the most appropriate. I read here that people were thinking of various ways to use a TT-30 outlet, but I didn't see anyone reporting back about what they found when they tried it. Is there a way to get the maximum number of amps out of the 120 volt, 30 amp, TT-30 outlet. I understand that the maximum is 24 amps, but the RAV4-EV limits 120 volt charging to 20 amps. I have an adapter (which I haven't tried yet) that will adapt the 5-20 plug on the Jesla to the TT-30, which is supposed to charge at 16 amps. I was wondering if anyone was able to do better?

That's an easy one. First, get a NEMA 14-30 plug for your JESLA:

http://shop.teslamotors.com/products/nema-14-30


Then either have us build an adaptor, or build one yourself:

TT-30P to NEMA 14-30R


DANGER: MARK THIS ADAPTOR "FOR EV USE ONLY - 120 VOLTS"


Your JESLA will be properly signaled that it is on a 30 amp circuit, and will tell the car to pull 80% of 30 amps, or 24 amps.

But, as you are aware, Tesla powered cars like the 2012-2014 Toyota Rav4 EV, prior to 2015, were limited to 20 amps on 120 volts (which is what "30 amp" trailer service is). The newer TESLA cars will do 24 amps.

So, this adaptor set up will allow 120 volts at 20 amps on a RAV4 EV, and 24 amps on new Tesla cars. Even the Nissan LEAF can pull 28 amps on 120 volts, which is why you need the JESLA properly signaled for a 30 amp circuit.
 
That sounds great. I ordered the Tesla 14-30 adapter plug for my Jesla the same day they put them back on the site. It should be here shortly. I'll order the TT-30R to NEMA 14-30P adapter from you on your website.


John
John Blair
 
jgblair said:
That sounds great. I ordered the Tesla 14-30 adapter plug for my Jesla the same day they put them back on the site. It should be here shortly. I'll order the TT-30R to NEMA 14-30P adapter from you on your website.


John
John Blair

I got that backwards... it should be TT-30P to NEMA 14-30R.
 
I use two tt-30
Combine them with a quick 220 20 amp with L5-20 female socket.

Then I use the umc

And the 20 amp Nema 5-20 adapter.

Get a custom made adapter from quick charge power

L5-20R male end

NEMA 5-20p. Female end.

And presto. You have 240v at 16amps
 
smkettner said:
Why combine 30s to a 20? Combine to a 30 and get 24a 240v.


The Voltage Combiner by System 220 that I have only supports 20 amps. Someone could make a 30 amp version but i just don't know how.
http://www.quick220.com/220_catalog/voltage-converters.html
 
The schematics for online, try searching the mynissanleaf forum for "quick 220". Just build it with #10 wire and 30 amp relays and connectors.
 
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