Wednesday, October 28, 2015

Trial Fit

Quick update: One fender and the nose panel are loosely in place, checking for fit.

The paint and finish on the front is gorgeous! The rest of the car looks faded and dusty now, but Robert thinks it should polish out nicely.

Still concerned about hood clearance on the front of the inverter, but the fender line is about an inch higher than the reference point on the inner fender wells, so we could just make it.

Robert has finished the headlamp covers and is working on the nose panel.

You can't see it, but one air conditioner hose is connected to the compressor and the other is out for fabrication and should be here early next week. Things are happening fast now, I'm very pleased with the progress!

Monday, October 26, 2015

Back to the Shop!

You'll recall that there were several contactor casualties from the precharge drama, along with some mysterious memory loss in the charger and DC/DC controllers. First the precharge situation: after frying the second set of contactors, I wired a couple of indicator lights to check the GEVCU precharge function and noted that they BOTH came on momentarily when the system was powered up, then followed the precharge sequence. That momentary inrush of current was all it took to weld the contactors closed. I also noticed during that momentary start-up period that the cooling fan spun just a bit.

At EVCCON, I checked with Collin Kidder who wrote much of the GEVCU code, and he said he had heard of this from several other guys and that it seemed that in the split second it took for the processor to boot up, the mosfets that were supposed to connect to ground under program control, all connected by themselves. Not good.

Nick Smith suggested taking the GEVCU out of the equation by using a time-delay relay to control the precharge sequence. I found this on Amazon that seemed to fill the bill, and picked up two more contactors from the EVTV store. All mounted to a panel, it looks like this:

The contactor on the left closes at startup connecting the negative side of the pack to the inverter. The gold colored precharge resistor then restricts the current flow from the positive side to allow the capacitors to come up to pack voltage at a lower current. The time delay relay closes after roughly five seconds and connects the positive contactor allowing full current flow. An indicator light is wired to the normally closed terminal of the relay so there is a visual cue on the dashboard while the precharge is taking place. All of this works very well and has kept the contactors healthy.

In the controller situation, Jack Rickard had reloaded the flash memory on my DC/DC controller and re-enabled the WiFi function on my GEVCU while we were at EVCCON. I reinstalled the DC/DC when I got home and BLAM! lost the memory again. Jack asked me to return the controller along with the Volt APM. He found that the plug was bad, and built a whole new controller. Thanks Jack - great customer service!

The DC/DC controller came in a new style enclosure that included tabs that made it so much easier to mount.

While all that was going on, I noticed that the charge controller kept losing its settings. So here we have wiped out the flash memory on the DC/DC controller twice, the EEPROM on the charge controller any number of times, and the WiFi function on the GEVCU. What's the common denominator? The USB cable! I broke out a new USB cable, one with gold contacts and perhaps a little better quality, and everything works just fine now. Moral of that story, don't overlook level 1 diagnostics; Is it plugged in? Is the cable good?

Took son Freddy and daughter-in-law Tiffany for a ride around the block and I'm becoming more and more pleased with the way this car drives. I was wrapping up some of the detail work, installing the hood release cable, running wiring for the dashboard, and generally tidying up the motor compartment when Bob called from Pro Automotive to let me know that they had a relatively slow week ahead and this would be a perfect time to get the car in for reassembly of the front bodywork. Called for a flatbed and now the PorschEV is in for finishing.

After a full year of work, this project is coming to completion. There is plenty of tweaking and tuning ahead, but the end is in sight.

Thursday, October 15, 2015

The EVCCON that wasn't ... or WAS IT?

After announcing the cancellation of EVCCON 2015, Jack Rickard noted with some bemusement that it just didn't want to be cancelled. He left the door open by offering his shop for an open house to whomever might care to visit, and it looks like pretty much all of us did. I had a hotel room and rental car all lined up, so I figured, "for a couple of days, why not?". And since the Porsche wasn't going to make it, I'd be traveling light anyway. Others like Michael Brown and Nick Smith were in the middle of global tours, coming from Thailand and New Zealand respectively. They were going to be there regardless. Speakers like John Hardy from the UK offered to do their thing anywhere there was a laptop and a projector, so Jack set up the showroom/studio of his shop classroom style and EVCCON 2015 took on a life of its own.

Once again Michael Brown did a superb job of live blogging the proceedings, so I'll direct you to his site again for the synopsis:

Day -1:…/…/evccon-2015-day-1.html

The session room was comfortably full and the information exchange with speakers and other attendees was more than worth the trip. 

Jack's direction for EVTV is all about making OEM components accessible to DIY guys like me, so that was the focus of the presentations and most of the break time chatter in the shop. A highlight of my last afternoon was the demonstration of a working Tesla drive train.

And there were cars - here's a sample:

All had been to EVCCON before, but it was good to see them again. Most had some detail improvements, and that's what makes these things fun. I'm disappointed that my Porsche wasn't ready in time because it really models the new direction, being fit almost entirely with OEM components. I brought along some problematic components that needed attention, and Jack was more than kind to give me his time to reload software and reconfigure settings. More on that in a future post.

In the previous four years of EVCCONs, the Thursday night barbecue at the Rickard estate had rained out. Not so for the EVCCON That Wasn't. Beautiful autumn weather and a spectacular setting overlooking the Mississippi river were on tap this year.

Many of the EV conversions made the short trip from the EVTV shop, and looked perfectly at home in front of the garage where the early shows were shot.

Of course Jill's Tesla looks right at home, because it is.

On a cool October evening, the fire pit was a welcome gathering spot. I said my farewells after the dinner because I was heading back to Austin in the morning, but EVCCON 2015 continued on without me. I hope we have not seen the last of these events, because all of us work in relative isolation and hunger for the opportunity to hang out with others who share our passion.