Update January 20, 2014
As documented below, it is possible to convert a Roadster to J1772 so that it can be charged directly from a standard J1772 charging station. Cathy and I developed a solution that is J1772 compliant (supports the proximity switch), is professionally manufactured, and supports full 70A charging.
Unfortunately, there are a number of pending issues that have caused us to halt work on the project.
Original Post
Cathy and I, with help from Dave Denhart and many others in the Tesla and broader EV communities, have demonstrated a conversion method for our 2008 Roadster and Tesla High Power Wall Connector to use the new industry standard J1772 inlet and plug. This will allow us to charge without an adapter at the tens of thousands of Level 2 charging stations that will be installed in the US by the end of 2011.
What we have is functional and completely reversible, but not ideal; we view this as a version 0.9 conversion. As there are very few J1772 charging stations currently installed, and the numbers probably won't take off until late spring or early summer, we have time to develop a better solution before it actually becomes compelling for Tesla owners to convert in significant numbers.
I'm sure Tesla Motors could do a much better job of creating an integrated solution and I would prefer that to having the owner community develop a conversion solution.
Our next steps are:
1) Hope that Tesla Motors provides an official conversion solution before it matters to most owners, thus saving us the remaining steps.
2) Design a circuit to monitor the proximity pin and disconnect the pilot signal when the J1772 plug is unlocked.
3) Test with other J1772 plugs and possibly work on a better solution for cable clearance over the body panel.
4) The 2010 and later Roadsters have the inlet cable assembly connecting to the PEM in a different location. There may also be other differences. We haven't looked into it yet and don't know if it will be more or less difficult to convert than the 2008 Roadsters.
5) Before recommending an unofficial conversion to other owners, we'll need to find out how this will impact our warranty. Tesla Motors has been cooperative with our efforts: they sold our group an inlet cable assembly so that we could do the conversion reversibly. We hope they will continue to be supportive rather than forcing us to wait until our warranties expire before being able to effortlessly access standard J1772 public charging stations.
For more details on our project and what still needs to be done before we can recommend that other owners do the same, see my blog.
As documented below, it is possible to convert a Roadster to J1772 so that it can be charged directly from a standard J1772 charging station. Cathy and I developed a solution that is J1772 compliant (supports the proximity switch), is professionally manufactured, and supports full 70A charging.
Unfortunately, there are a number of pending issues that have caused us to halt work on the project.
- When I asked for owners interested in doing the conversion in September, 2012, I got very few responses.
- Henry Sharp has the compact CAN adapter which can be locked to the car. It's so much better than the Tesla adapter that the conversion has less appeal.
- Because of the stupid "gas nozzle" shape recommended for J1772 connectors, it's hard to get a connection because of interference with the body panel below the port. With a lot of hacking on the mounting plate and cutting away part of the inlet wall, it kind of works with the ITT Canon 80A connector, but other J1772 connectors don't work as well.
- The idea of switching public HPCs to standard J1772 stations so they are accessible to all EVs seems great, but I worry about the stations being taken by more prevalent 3.3/6.6 kW cars. Keeping the Tesla Roadster HPCs with the Roadster connector limits access to the few vehicles that can charge at 70A or more (Roadster and Model S). Obviously the equation may change if those HPCs go away and we start getting more public high amperage J1772 stations.
- We haven't made any progress on a conversion cable for v2.x Roadsters. Although we thought the v2.x case would be easier than the v1.5 because of the much simpler connection to the PEM, sourcing a cable that matches the original Tesla cable (so that no PEM modification is needed) has proven difficult.
- There's a little more work left to be done on the v1.5 cable. The folks at the cable company have been great, but the low expected volume is a barrier to getting it finished and into production.
Original Post
Cathy and I, with help from Dave Denhart and many others in the Tesla and broader EV communities, have demonstrated a conversion method for our 2008 Roadster and Tesla High Power Wall Connector to use the new industry standard J1772 inlet and plug. This will allow us to charge without an adapter at the tens of thousands of Level 2 charging stations that will be installed in the US by the end of 2011.
What we have is functional and completely reversible, but not ideal; we view this as a version 0.9 conversion. As there are very few J1772 charging stations currently installed, and the numbers probably won't take off until late spring or early summer, we have time to develop a better solution before it actually becomes compelling for Tesla owners to convert in significant numbers.
I'm sure Tesla Motors could do a much better job of creating an integrated solution and I would prefer that to having the owner community develop a conversion solution.
Our next steps are:
1) Hope that Tesla Motors provides an official conversion solution before it matters to most owners, thus saving us the remaining steps.
2) Design a circuit to monitor the proximity pin and disconnect the pilot signal when the J1772 plug is unlocked.
3) Test with other J1772 plugs and possibly work on a better solution for cable clearance over the body panel.
4) The 2010 and later Roadsters have the inlet cable assembly connecting to the PEM in a different location. There may also be other differences. We haven't looked into it yet and don't know if it will be more or less difficult to convert than the 2008 Roadsters.
5) Before recommending an unofficial conversion to other owners, we'll need to find out how this will impact our warranty. Tesla Motors has been cooperative with our efforts: they sold our group an inlet cable assembly so that we could do the conversion reversibly. We hope they will continue to be supportive rather than forcing us to wait until our warranties expire before being able to effortlessly access standard J1772 public charging stations.
For more details on our project and what still needs to be done before we can recommend that other owners do the same, see my blog.
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