Still working on the voltage sag on the 12 volt system. The symptom is that the controller error light blinks when both the brake lights and turn signals are on when the headlights and cooling pump/fans are running. Swapping the 30 amp DC/DC converter out for a 44.5 amp version reduced the incidence of the low voltage warning, but when headlights, brakes and turn signals were in play, it remained an issue. I found these at the local auto parts store:
They promise to drastically reduce the current draw while giving a brighter light than the old fashioned filament style bulbs. With resistors built in, there's no need to add a load to work with the existing flasher.
Installation is easy, just remove the tail light lens and replace the old bulbs with the new LEDs. They look clear, but actually give a red light when powered. The new LEDs are on the left and the old bulbs still on the right. I can't say that the LEDs are that much brighter in the daylight, but they are certainly no worse.
The proof is in the testing and early results are good. The first thing I notice is that when flashing there is no fluctuation in the voltmeter reading, where there was a very clear "tic" up and down on the needle before. A quick drive on my favorite test route with the headlights ablaze got the cooling pump and fans running. The voltmeter was showing a constant 12.5 volts, and it held steady at that level when the turn signal and brakes were applied, so I'm going to declare success.
The next step will be to swap out the old sealed beam headlights for LED replacements to get a brighter light out front. At around $260 each ($520 a pair) though, that will have to wait a while.
When we first moved to Austin, we saw a lot of these bumper stickers:
We thought it a bit quaint, but it's true! Sunday I got to be a part of some of the weirdness. The AustinEV club sponsored a display at the Mini Maker Faire at the Palmer Events Center on the south shore of Lady Bird Lake.
The list of exhibitors was long and eclectic: everything from vintage costumes to making mud bricks to a huge Lego railway to weaving to robots to home composting to an inflatable planetarium. Click here to a see the exhibitor list. Here's a video that captures the variety of stuff that was going on:
There were all kinds of activities for kids - they could get their faces painted and ride on a big butterfly bike, see a Star Wars Jedi Fighter, and create their own custom bars of soap:
Also on display were a Saturn and a Jeep, so we had a cross section of cars from off-road to sports car to family sedan. There was a steady stream of interested visitors, almost universally positive about the conversions. This was a very "green leaning" crowd, so there were very few of the critical questions we often field about return on investment or perceived shortcomings. In the case of the evTD, mostly wonder at how a classic like this could be made electric.
Photo courtesy of Mary Jackson
I did chat with one lady who said they were expecting their Tesla Model S delivery in a couple of weeks and several Dell employees who said that there were new charging stations at work so driving electric was starting to make sense. I'm not sure if we moved the EV ball forward much, but there was certainly a positive vibe around this show. We were positioned right next to the bandstand, so it was a bit rough carrying on a conversation at times. The highlight of the music scene came when the last musical group made their appearance late in the day. The Dead Music Capital Band marched(?) from the main entrance to the stage and gave a concert that had everyone asking "Huh?!"
Austin bills itself as the "Live Music Capital of the World", so the DMC band is - you guessed it - zombies playing tunes to wake the undead. Here's a sample:
Did I mention "Keep Austin Weird"?
In other news, This is the longest trip I've taken to date in the evTD, 39 miles on 57Ah. That's 1.45Ah/mile and extrapolates into a real-world range of 55 miles to an 80% depth of discharge. I'm actually pretty pleased with that given that the evTD has the aerodynamic drag coefficient of a cinder block.
I'm taking the evTD to the "Maker Faire" show tomorrow, and based on a comment from Jarkko Santala, I'll be adding a clear acrylic cover to the component box so people can satisfy their curiosity about what's in there. It also occurred to me that I should put together some info sheets and signage to answer some of the recurring questions that are likely to come up. First I printed out the contents of this blog and organized the pages in a three ring binder.
That way I can show thestepsinvolved from beginning to completion. Or people can leaf through at their leisure if I'm in a conversation with someone else. I also put together some placards that give basic information at a glance. These can fit against the front of the windscreen, held in place by the windshield wipers.
It also occurred to me that it would be nice to provide a take-away sheet for people who show real interest and might like to follow up. I'm only printing twenty five, so these are not for everyone, and I'll have to be a bit selective on how they're distributed. Here's the front and back:
and the inside:
I'm also designing some simple business cards that point to this blog for further information. Seems the last time I did a car show I had to write it down about a hundred times.
Continuing the refinement process, I added two little neoprene bumpers to the motor hatch in back to stop the rattling - not much to see there. Also devised a way to lower the soft top without pulling all the snaps off the back (which is a real pain, literally). Securing the folded top with velcro straps keeps it from flapping around in the slipstream.
The straps are attached to the spare tire supports by simply wrapping the velcro around the support tube.
The corners still tended to lift at speed, so another velcro strap on the diagonal from the folded top frame to the spare tire support got that under control. The evTD is taking part in the "Maker Faire" show this weekend at Austin's Palmer Events Center. This show is about DIY activity of all sorts. Because it will be a crowd that isn't familiar with electric vehicles, I wanted to complete something I started eight months ago and never quite got around to. You may recall that I originally configured closed boxes to contain the miscellaneous electric bits where the most positive and most negative cables attach to the pack. In the crunch to get the project finished for EVCCON, I took a shortcut and attached the shunt, fuse, and current sensor directly to the front platform.
It seemed OK for EVCCON where everyone is knowledgable about circuits and wouldn't be touching exposed 230 volt connections, but I felt it needed to be "finger safe" for a more generalized audience. The negative component box was pulled off the shelf and configured with the shunt, fuse, and current sensor inside.
I remembered why it didn't get done the first time - I needed to re-build the current sensor link so it was about an inch longer and had the gland nut in place before crimping on the lug. With that done, it went together nicely.
It fit the space well and tidied up what had been a busy looking, somewhat cobbled up area. With the cover installed it looks almost like I planned it that way.
The other new item you'll notice is the maintenance switch on the upper platform. It's become apparent that the DC/DC converter needs to run full time to keep up with the "always-on" 12 volt loads; the GPS speedometer, radio, BMS, and JLD 404 amp-hour meter. The maintenance switch gives me another way to disconnect the pack in addition to the emergency contactor.
After visiting the Tesla Showroom yesterday, I'm on my way to play a concert this morning with my quintet and noticed a new sign on Burnet Road, Tesla Service. I resolved to stop and check it out after the concert and glad that I did!
That's my Nissan Leaf parked out front. No signs of activity, so I walked around the side and there were two Tesla Model S sedans parked outside. Taking a closer look through the open shop door made my jaw drop ...
Inside were eight more Model S's being prepped for customer delivery, along with a customer owned Roadster in for service. That's well over a million dollars worth of Teslas in one place.
I had a chance to chat with a customer who took delivery of his car yesterday and one of the service techs who was supervising the detailing activity. They confirmed the impression I got from the showroom yesterday that Tesla views Austin as a key market and is taking a serious initiative here. I wish them the best! Maybe in two years when the lease is up on my Leaf, they'll have built their volume enough to pull the price down to something I can consider.
The new Tesla showroom opened here in Austin last weekend. The showroom is situated on the main shopping street of The Domain, a high end mixed retail, residential, office, and restaurant development on the old IBM Austin factory site. The opening coincided with the start of South by Southwest, the annual film/music/technology festival here in Austin. The weather was quite lovely on a Tuesday afternoon so I decided that a visit in the evTD would make a for great outing.
The store front is kind of long and narrow, just fine for showing off the Model S that was front and center, along with displays for the color and material options along with some diagrams of the technology. The attendants are young, bright, articulate, and seemed well informed on their product and market. They said Elon Musk had visited the Grand Opening on his way to deliver a keynote address at SxSW.
In the back of the store was what I was told is one of the few remaining Tesla Roadsters for sale. The Model S is gorgeous and eminently practical, but the Roadster still is the one that gets me charged up (pardon the pun). I think Tesla has chosen the right place to market these since Austin demographically has the money - lots of tech people cashed in on the bubble before it burst - and a strong "green" attitude.
They let me sit in the driver's seat, and I was impressed with the materials and finish of the interior. It is definitely a cut above my Nissan Leaf as well it should be. The available range on the display said 244 miles, also about three and a half times the Leaf. You get what you pay for, and the relative value seems to be appropriate. The exterior is top quality as well, a very well turned out motor car.
When I told them I had driven my converted MG TD, the staff got excited and wanted to see it, then wanted pictures of my car in front of the store. Some other patrons came out of the shop and I gave them a look under the hood and the boot with a general show and tell about the car's components and the process of doing the conversion. Lots of interest and I didn't even mention that I was driving electric for a fraction of the cost.
Now if my inheritance from that unknown uncle in Nigeria comes through, I'll be back to put a deposit on a Model S.
A project like the evTD is never really "finished" and there is always something to refine or improve. There was literally no time to shake down the car between the time I stopped work on it and towed it off to Cape Girardeau for EVCCON. Once I got there, I noticed that running at night made the controller error light blink. The controller quit a few times when I applied the brakes at a stop light, but always restarted right away. I thought I had a controller problem, but it remained a mystery. After I got home, my excursions were mostly in the daylight and no issues. Finally I drove it to an orchestra concert and drove home after dark with the headlights on and when I saw the error light blinking, I glanced at the voltmeter for the 12 volt system and it was hovering about 11 volts. Adding brake lights or turn signals took it below 11 volts. Clearly my 30 amp Iota DC/DC converter wasn't keeping up with the power demands of my 12 volt system. After a conversation with Steve at Rebirth Auto, I decided to upgrade to a 44.5 amp Meanwell DC/DC Converter. It arrived just before Christmas, so I had the wife wrap it up as my gift from her. Santa strikes again! Here is the under-hood with the Iota as originally configured:
and here after the Meanwell was installed in place of the Iota:
Not much difference visually, but the first after dark run proved it was a worthy upgrade as the voltage stayed pegged just above 12 volts with all the lights, brakes, signals and wipers running.
The Iota was never a problem when it was installed in the e-Bugeye, so the difference in the evTD would have to be the coolant pump and fans. The e-Bugeye was air-cooled, but with the evTD's Soliton1 mounted directly above the Impulse9 motor, liquid cooling was a necessity in Texas heat. That added just enough current draw to put the Iota over its 30 amp limit, resulting in voltage sag. Now there are no alarms from the controller with the added bonus of brighter lights all around.
