Short and sweet J-1772 to Roadster adapter - lockable

[hcsharp]

rgjones thank you so much for your support! You've been a big help and I wish I could afford to give you a commission!!!
:redfacetrying not to feel guilty now for making you pay for a prototype...)
Seriously, really glad to hear it's working out!

Yes, I charged at 70A no problems at the Rabobank Goleta using a prototype.
A fellow roadster was getting 'extension cord' detected VDS messages using the Tesla extension, no such nags with Henry's master piece.

BTW, Having an early access prototype, I've racked up a couple of months charging almost daily at 30A, mostly on blink chargers and had no problems.
Great product - Thanks Henry!

 

[Timothy]

Then you can plug or un-plug the J- connector coming from the EVSE while the adapter remains locked to the car.

My unit arrived today and I am eager to buy the padlock try charging with it tomorrow!

One of my new techy friends I met at Earth Day here in Santa Barbara was concerned that disconnecting the J-connector without turning the charging off in the car first could blow a fuse. Do you think this extra step of turning the charging off in the car first is necessary?

 

[TEG]

Pressing the release button on the J-plug, and starting to pull it out is supposed to tell the car to stop charging before the power pins get disconnected.
Do we know if that mechanism is preserved through this adapter? I think Tom Saxon had some concerns about that sort of thing.

 

[doug]

Pressing the release button on the J-plug, and starting to pull it out is supposed to tell the car to stop charging before the power pins get disconnected.
Do we know if that mechanism is preserved through this adapter? I think Tom Saxon had some concerns about that sort of thing.

Seen here:

We've made some progress on a more robust Roadster J1772 conversion. As part of the conversion, we want a circuit that monitors the J1772 proximity pin and cuts the pilot signal when the latch on the connector is released. With such a circuit, a Roadster will behave as a proper J1772-compatible EV and stop the current flow when the J connector's latch is opened, thus preventing any damage to the connector pins which can occur when pulling out the plug while charging.

Cathy and I worked up the basic idea together and got a bunch of help from the EV community. Cathy put in a ton of work selecting components, soliciting feedback, iterating the design, and designing the circuit board. Our solution works without drawing any power from the car, it just uses a tiny bit of power from the incoming line voltage during charging.

We just got the first set of boards back, put one together, and tested it. It works beautifully, performing even better than I had hoped. The response time from when the switch on the connector is pressed until the pilot signal is cut is about 2.2 milliseconds. When hooked up during a charge, there's no perceptible delay between when the J1772 latch is pressed and when the Roadster stops charging.

Even more geeky information is available on Cathy's page of cool details.

The Roadster, as is, doesn't use the proximity signal part of the J1772 standard. This was fixed on the Model S.

 

[TEG]

So, I gather that means it would be good practice to stop charging from within the Roadster, or using an "off" button on the EVSE before unplugging the J-plug from the Roadster adapter...

 

[vfx]

So, I gather that means it would be good practice to stop charging from within the Roadster, or using an "off" button on the EVSE before unplugging the J-plug from the Roadster adapter...

We had a conversion in Fashion Island with those who are E-knowledgeable Tom and Jim and the answer was exactly the above^. Anything else would need to be tested (on someone else's car

 

[hcsharp]

Pressing the release button on the J- connector, which you have to do to pull it out, stopped the current flowing within a few milliseconds every time I tested this. edit: But not all EVSEs will do this! Read more below./end edit. It first interrupts the proximity detect which causes the J1772 EVSE to immediately stop the pilot signal. When that happens the Roadster stops taking current usually at the next AC crossing (when the voltage is 0 in an AC sine wave), taking at most 16 milliseconds.

I have tested this on 2 different brand of EVSE and in both cases it performed as expected. edit: But not all work this way! You press the lever and there is no perceptible delay before power stops.

In summary, it's best to stop charging at the EVSE first, which they all recommend, or with the Tattler, or with the stop button on the VDS, and then by pressing the release button on the J connector.

As a secondary precaution, the pilot pins on both my adapter and the Roadster are intentionally shorter than the power pins. Thus even if the EVSE failed to shut off the pilot as expected, the pilot pin would disconnect first and the Roadster would stop taking current before the power pins disconnected.

As a third precaution, the sleeves that I used on the Roadster side are rated for up to 20 live disconnects at 80 Amps during their lifetime. So all of the above would have to go wrong 20 times before any significant damage occurred to the adapter. You are probably more likely to get hit by a comet.

To address another issue mentioned, even if you do a live disconnect, it will not cause the battery fuse to blow. It is essentially the same as a power outage while charging or having the contactor open in the HPC due to a GFI fault. The Roadster is designed to withstand these events, even if it doesn't particularly like them.

Tom Sax was converting an HPC that did not have any proximity detection which would not be the case with all J1772 stations. Therefore he had a much bigger incentive to handle it reliably with a separate circuit in the car. In theory he could have achieved a similar result by interrupting the pilot signal with the release button but then the system would have been technically out of compliance with J1772 and had unpredictable results charging other cars.

Hope this helps!

 

[TEG]

Yes, thanks for taking the time to explain all that !

 

[dpeilow]

Sounds like you've really thought that through. Good job.

 

[strider]

A good use for a Tattler/OVMS to stop the charge as you approach.

 

[hcsharp]

Sounds like you've really thought that through. Good job.

Yes, thanks for taking the time to explain all that !

Picture me at a public charging station 90 miles from home, oscilloscope in one hand, strange looking adapter with test leads dangling in the other, trying not to electrocute myself, drawing some quizzical looks, collecting data... :scared:

 

[TEG]

// warning... going off topic //

Picture me at a public charging station 90 miles from home, oscilloscope in one hand, strange looking adapter with test leads dangling in the other, trying not to electrocute myself, drawing some quizzical looks, collecting data... :scared:

You have inadvertently led me to my favorite Google search ever... "strange gadget" returned these among others:

 

[vfx]

// warning... going off topic //



You have inadvertently led me to my favorite Google search ever... "strange gadget" returned these among others:

Have one!

Even used it in a camping situ just like pictured. Perfect when only two can fit on a mountaintop.

 

[Bradleybang]

I am on a trip to Pebble Beach for the weekend. Realizing the stations have all gone j1772 I ordered one of Henry's adapters. He was kind enough to overnight the part with my FedEx account. As I type this message my car is charging at 70A at Rabobank in Salinas.
Photo to follow.

Thank you Henry. It's better than the pictures.

 

[Botbldr45]

I just received mine - only ordered a couple of days ago! Thanks.

smorgasbord, I'll run up to the Clipper Creek charger in Auburn and try it out on their 70amp J1772. Give me a couple of days.

Would love to get one ......
Who do I contact and would anybody like a Tesla version ( never used)......

 

[bonnie]

Send hcsharp a pm (first poster in this thread).

 

[bonnie]

fyi - for those of you who buy - a camera lens case is perfect for storage. The adaptor measures approx 6.5" long x 3.25" diameter (or 165mm x 82.55mm). Plenty of padded lens cases on eBay, like this one:

 

[DrTaras]

Plenty of padded lens cases on eBay, like this one:

Thanx Bonnie!

 

[Botbldr45]

Thank you ..... Just did it

 

[doug]

No demo vids yet?