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Roadster Conversion to J1772 Charging

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I have a 2.0 Roadster being delivered to me and I just want to make sure that I have everything I need to charge the car. There is a Coulomb tech tall boy near my office that has a J1772 plug - so basically if I want to use it, I need to purchase a converter AND get a firmware update?

thanks

If you want to get a converter, you should check out the thread on Tesla's adapter. This thread is about converting Roadsters to use the J1772 inlet natively, without an adapter.
 
What's interesting about that approach is that if we create our own pigtail and locate it to the left of the PEM on the 2.x cars, we've not fiddled with the TM wiring & if needs be, TM can unplug the pigtail and access the original inlet during service, etc.

Another location might be the huge space where the subwoofer goes.

Exactly, it changes nothing at all about the car and still allows charging via the original inlet. Simply open the trunk, unplug the J1772 adapter from the original inlet and you can then still charge for a Tesla HPC, for example if needed.
 
I tested charging a 2008/1.5 Roadster from a public ECOtality Blink charger at a press conference opening four Blink stations at Qwest Field. I used the adapter Cathy and I built last September, which is equivalent to Tesla's adapter. It worked great.

TeslaBlink.jpg


Yep, that's right, our Roadster is on the Blink. :biggrin:

The ECOtality guys there said I was the first Roadster to try one of their public Blink units. I still need to try one of the home Blink units that people in The EV Project get. I'm also interested to hear if a 2.x Roadster will work with both types of Blinks.

It pains me to be using the clunky adapter, but we're back to having the Tesla inlet on the car while we're working on a better cable for the conversion.
 
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The Coulomb guys there said I was the first Roadster to try one of their public Blink units.
Isn't Coulomb a different company from Blink?
(Coulomb does the ChargePoints, right?)
I still need to try one of the home Blink units that people in The EV Project get.
From your pic, those public units look like they might be the same as the home units.

I offered to let DWegmull try his Tesla<->J adapter on my home Blink if he wants...
 
Isn't Coulomb a different company from Blink?
(Coulomb does the ChargePoints, right?)

Yes indeed. Thanks for catching that mistake. I edited my post to correct it.

From your pic, those public units look like they might be the same as the home units.

I offered to let DWegmull try his Tesla<->J adapter on my home Blink if he wants...

I'm sure it runs a lot of the same hardware, but the packaging and feature set are different. I did try charging from a Blink home unit over the weekend. It went through a couple of start/stop cycles when I first plugged in, but then it charged (30A) just fine.

I wonder if their data collection will notice the charge at a home install that doesn't have a LEAF yet. :smile:
 
...I wonder if their data collection will notice the charge at a home install that doesn't have a LEAF yet. :smile:

I got the Blink before the Leaf arrived too.
I was able to charge the old Ford RangerEV using a J to Avcon adapter cable.
It didn't seem to cause any issues. No one called me, and the Blink is now serving both the new Leaf and the old RangerEV. (One at a time of course.)
 
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Progress on the conversion effort...

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.

board.jpg


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.

In other news, the cable vendor that said they could produce the replacement inlet assembly cable for us took six weeks of excuses and delays to finally say they don't want to do it. So, we're back to the drawing board on that.
 
One question: Does the Tesla pigtail include this? I haven't heard that it does. It could be susceptible to the damage that you mention.

When you disconnect the J1772, don't the pilot and proximity pins disconnect before the power pins do due to them being shorter? Or, does damage to the power pins occur as you slide them out?
 
To be clear, I don't know that arcing is going to be a big problem with Tesla's J1772 adapter. It seems to me that it could be a problem, and since it's so easy to fix, we're going to do it when we permanently convert our Roadster. We're also willing to share our fix with any owner who wants to do the same.

One question: Does the Tesla pigtail include this? I haven't heard that it does. It could be susceptible to the damage that you mention.

Tesla's J1772 adapter does not include this protection. I discussed this with Tesla and got this response:

While there is a possibility of arc, the J1772 connector, like all our other connectors and adapters, is designed and tested to prevent damage or injury when it is unplugged while charging. Unplugging the connector from the J1772 charging station is similar to someone unplugging the Universal Mobile Connector from the wall without manually stopping the charging first on the car side.

I see two differences from the UMC scenario: 1) we don't generally charge with a UMC at a mall where other EV drivers expect to be able to charge and may choose to unplug the UMC, and 2) if unplugging the 14-50 causes arcing, it's going to damage a $10 outlet and a $100 pigtail, not a $300 J1772 connector and a $750 J1772-to-Tesla adapter.

When you disconnect the J1772, don't the pilot and proximity pins disconnect before the power pins do due to them being shorter? Or, does damage to the power pins occur as you slide them out?

I've heard that before, but I don't see it in the J1772-2010 spec. Section 8.7.5 "Contact Sequencing" says only that the ground pins have to be the first to connect and the last to disconnect.

I notice that Tesla told me arcing can occur, not that arcing can't occur because of the J1772 plug design.

Even if the pin disconnection sequence is required, or done in practice on most connectors, I'm not so confident the car will stop pulling current in the fraction of a second between when the pilot pin disconnects and when the power pins separate. (The EVSE is allowed multiple seconds to disconnect power after losing the pilot signal connection to the car.) Once the plug is being removed, it's not going to take much time to cover some small difference between pin lengths.

IIRC, Tesla recommends that you disconnect the Tesla connector from the car (to stop charging) before you separate the J1772 plug from the adapter.

Yes, that's true. But they aren't doing anything to educate LEAF and Volt owners about how to safely operate Tesla's J1772 adapter rather than just unplugging the connector they want to plug into their car.
 
Yes, that's true. But they aren't doing anything to educate LEAF and Volt owners about how to safely operate Tesla's J1772 adapter rather than just unplugging the connector they want to plug into their car.
I think your idea is excellent and glad you're adding the fail-safe - Tesla should have added that to their adapter cable. I was simply answering mpt's question.

But, do other EV owners seriously unplug other people's cars? I'm not ok w/ that.
 
...But, do other EV owners seriously unplug other people's cars? I'm not ok w/ that.

The bigger problem is random curious people, usually kids/teens, unplugging it without asking.

But some owners do give permission for others to unplug their cable when the charge is done.
I have seen paper "will return" style clocks on the dashboard of some EVs changed to say "Fell free to unplug me after HH:MM"...
Kind-of like this, but relabeled:
195586_sk_lg.jpg
 
Just so everyone knows, I'm still working on the J conversion. I've found a cable vendor that I think will be able to build the J version of the inlet assembly cable with the quality we want. Things are slow, but hopefully I'll have some news soon.