Tesla Model S UMC cut open and modified to J1772

[mitch672]

Phil, nice work. Question for you: Is the door release transmitter contained in the Tesla Model S connector, that you replaced with the J-1772 end? The reason I am somewhat curious is, I bought Tonys now discarded Tesla end from him, hoping to use it on one of the several OpenEVSE builds I have.. It would be awesome if the transmitter is in the handle, and only needs to be supplied with 3.3V to the proximity wire for the charging door to release on the Model S (when the button is pressed of course). it also means you'd probably be able to sell (Or their would be a market for) the Tesla connectors if you did decide to modify additional UMCs for J-1772 use.

 

[TonyWilliams]

Mitch, did you do a pin-out of the wires on the Model S plug?

I need to verify the polarity that I failed to note before I shipped the plug.

Line 1-------------------Line 2
?Black? ---------------- ?Red????

Blue----------------------Purple
Proximity-----------------Pilot

--------------Green------------
--------------Ground----------

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Tony, Looks like your "no-name" handle is a new version. I'd say they've improved it. On the one I used, it appears they actually attempted to seal the housing from the weather, which is a FAIL. All they probably succeeded in doing is helping seal the water in. I solved this problem with a few well-placed holes.

The handle release mechanism has also been simplified in yours. Mine was overly complex and fragile, and has a fatal flaw in the proximity switch system, allowing the latch to be disengaged without tripping the switch. Luckily the good design of J1772 is somewhat double-redundant in this area, so it's not a big deal.

-Phil

I've decide to send mine off to a specialty shop for "mil-spec" grade crimping. Yes, they added drain holes in the new China-clone unit. The sockets are very snug on the J1772 pins in the car (wear and tear). The micro switch is WAY better.

 

[mitch672]

The connector arrived yesterday, I don't get home until 9PM, and then my multimeter was at work, and my backup needs new 1.5V hearing aid batteries. I'll get to it on the weekend, I want try applying 3.3V to the proximity wire anyway, and see if I can get the door release transmitter to work.

Not sure it matters which positions red and black go, will pin it out anyway, the important ones are "pilot" and "proximity", and of course ground.

 

[TonyWilliams]

Not sure it matters which positions red and black go, will pin it out anyway, the important ones are "pilot" and "proximity", and of course ground.

I read somewhere that the Tesla UMC was polarity sensitive at 120 volts... ok, that's not polartity, but neutral to hot sensitive. I have no idea if that's true, but I do want it set up the same way.

 

[mitch672]

Tony, your guess above is correct. Looking at the connector from the end:

Left Power pin: 2 BLACKs. Right Power pin: 2 REDS

Center pin: GROUND (GREEN w/yellow stripe)

Left: Proximity (Blue) Right: Pilot (Violet)

All wires are directly conncted to the corresponding pin, except for the Violet Proximity pin, it measures 1.8Meg Ohms between the Violet wire and the pin, a similar measurement is obtained between ground and the Violet wire.

Measuring the proximity pin at the connector, between ground and the pin measures 150 ohms, when the "release" button is pressed, the measurement changes to 480 ohms. Ingineer states Tesla supplies 3.3VDC on the proximity wire to power an RF module in the Model S handle that operates the charging door release on the Model S.. I will be connecting up a 3V battery source between ground and violet to verify that works

 

[FlasherZ]

Doubling up wires to increase current is against building code for permanent installations. Are appliances exempt from this rule?

Yes, the NEC "covers the installation of electrical conductors, equipment, and raceways; signaling and communications conductors, equipment, and raceways; and optical fiber cables and raceways" (NEC 90.2).

Appliances are generally subject to UL listing standards (in the US), although I understand the UMC isn't listed.

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I read somewhere that the Tesla UMC was polarity sensitive at 120 volts... ok, that's not polartity, but neutral to hot sensitive. I have no idea if that's true, but I do want it set up the same way.

It is true. The UMC requires > 0V between one of the hot pins (I forget which) and ground.

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Apparently, some of the Tesla portable EVSE (Model S "UMC") are burning up? I wonder if its a lack of energy absorption from being dropped? The interchangable plug adapters are also melting their connection pins (they are tiny)?

In my case, over time the weight of the UMC is pulling the pins between the receptacle adapter and the UMC plug away, which causes current to flow over less of a surface area, and it's melting the UMC plug-adapter connection.

 

[mitch672]

I connected up a 3VDC power supply today (ok, 2 AA batteries in a Radio Shack holder), wired between ground and the blue "proximity" wire, when the Model S detects your key present, and you press the button on the Model S charging connector, the door opens, confirming the actual RF transmitter is contained in the Model S connector assembly.

I am debating buying 20'-25' of Henries 80A EVSE cable, along with this connector to replace my ITT J-1772 75A cable, on my OpenEVSE, will end up being a home made HPWC

Evse Charging Cable 80 Amp 600 Volt UL Approved SAE J1772 | eBay

 

[vfx]

The cool thing is Tesla's inclusion of a handy 3.3v source which is normally used for the charge door release transmitter. This enabled easy addition of a bright LED for nighttime, something not even Tesla thought of!

...

They put a color changing ring of lights around the car socket. Why add a light in the plug? I guess in case you drop your keys in the dark.

 

[TEG]

They put a color changing ring of lights around the car socket. Why add a light in the plug? I guess in case you drop your keys in the dark.

The point of putting a J-plug on the end of a modified UMC is to use it on vehicles OTHER than the Model S (most of which don't have a light ring like you describe.)

 

[mitch672]

The point of putting a J-plug on the end of a modified UMC is to use it on vehicles OTHER than the Model S (most of which don't have a light ring like you describe.)

Exactly, and in particular the Toyota RAV4EV, which has a similar (or more likely, exactly the same) 10KW onboard charger as the Tesla Model S. There are no other portable EVSEs on the market that support 40A charging, Toyota supplies the same 120V only 12A J-1772 EVSE they use on the Plug in Prius... Sad really, how Toyota almost wants the RAV4EV to fail ("see I told you no one wants these EVs")

 

[TonyWilliams]

Sad really, how Toyota almost wants the RAV4EV to fail ("see I told you no one wants these EVs")

Almost on cue, the six Very Large Manufacturers are appealing to the EPA to stop CARB-ZEV regulations that require cars like the Rav4 EV.

 

[mitch672]

Almost on cue, the six Very Large Manufacturers are appealing to the EPA to stop CARB-ZEV regulations that require cars like the Rav4 EV.

Luckily, CARB and the EPA can come back with:
"Tesla doesn't seem to have problems selling its EVs, in fact they only make EVs"

 

[mpt]

Just a thought on the two-wire issue - Is the original Roadster UMC still available? That has one wire per conductor (per the cable description).

 

[TonyWilliams]

Just a thought on the two-wire issue - Is the original Roadster UMC still available? That has one wire per conductor (per the cable description).

Yes, and it's more "industrial grade". $1500, too!!

It won't have an adjustable pilot signal from the interchangable plugs, like the Model S.

 

[tpoltron]

Hi All,

I too made put a J1772 plug on a UMC so we can charge both our Model S and the electric Fiat 500e we get next week.
Like Ingineer Phil says crimping double undersize wires into oversize holes is more fiddly that you think.

There was one gotcha that tripped me up for a couple hours: I connected the Proximity pin to the resistors in the plug and to the proximity wire in the UMC. It should only be connected to the resistors - the 3V from the UMC put the Model S in don't charge error mode.

If anyone is interested, I'm selling the Model S UMC plug.
Tesla Model S UMC Plug for sale

Regards,
Trent

 

[tpoltron]

Just an update that my J1772 modified UMC has been working well for charging both my electric Fiat 500e and our Model S through the adapter.

 

[Chris1howell]

I went the other way and put a UMC cord handle on a OpenEVSE. It's working great including the button to open the charge port.

 

[TonyWilliams]

Chris, I have already sold some of these "extra" UMC plugs for $50, so if you need one in the future, let me know.

I am doing a batch of 10 UMC's being converted to J1772, primarily for Toyota Rav4 EV owners stuck with a 12 amp / 120 volt EVSE that adds 3 miles per hour!!!

 

[mitch672]

I'm putting one of the UMC Model S plugs that I bought from Tony on the "JuiceBox" when it arrives in August/September. They now state they are using #6AWG wiring internally and 80A relays/contactors. We'll see...

 

[Chris1howell]

They now state they are using #6AWG wiring internally and 80A relays/contactors. We'll see...

Wow 80A... I don't see how they can do that for the price, unless they are planning to include inexpensive SSRs from China which sell for ~10 on ebay. I hope that is not the case as SSRs are a very bad idea (and not safe) for an EVSE.

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Chris, I have already sold some of these "extra" UMC plugs for $50, so if you need one in the future, let me know.

I am doing a batch of 10 UMC's being converted to J1772, primarily for Toyota Rav4 EV owners stuck with a 12 amp / 120 volt EVSE that adds 3 miles per hour!!!

Thanks Tony, I'll keep that in mind.