Electric 914 Progress Thread, (or, 'What Shannon Did Today') Options

[neo914-6]

Here's the Electric Crossfire and PT brochure. Backers are probably crooks but somebody built a nice conversion. (IMG:style_emoticons/default/smilie_pokal.gif)

[sgomes]

Wow! It's getting so I can't keep up with my own thread!!!! Sorry for being away for a bit. Had a little birthday there and somehow I just didn't find the time to get on the 'puter. (IMG:style_emoticons/default/rolleyes.gif)

thanks for the birthday wishes and thanks for the compliments on the conversion. The status at this point is that it's back in the garage for a bit. (IMG:style_emoticons/default/sad.gif) I'm having intermittent drop outs. Push on the pedal and absolutely nothing happens. It seems to repair itself in a few seconds but as you can imagine that doesn't impress me. So it's back to the (IMG:style_emoticons/default/smash.gif) (we don't have a smiley for poking around with a DVM)

As far as the efficiency goes... it doesn't have anything to do with how far I can drive on a "tank" It is waaaaayyyyyyyyyyyyyyyyy more complicated than that. I've cruched the numbers in all kinds of differenct ways. The value that I come up with that is the most satisfying is around 80mpg equivalent. That is to say, all things together my car is the equivalent efficiency wise of an 80mpg ICE car. But before you get your panties in a wad trying to debate this number, let me just say there is a whole lot of guess work you have to do about oil/ng/coal/etc - to - electricity conversion efficiencies and powerline transmission losses and oil tanker gas mileage blah blah blah blah..... It's ok to say we may never know the correct number. If you want to get basic about it then just look at the watts in vs watts out. I'll let you crunch the numbers but this is where the electric car blows away the ICE car. It's really scary when you realize how many "watts" are in a tank of gas. You'll be very upset that you can only go 300-400 miles per TANK!!! If I could get that many watts in a tank..... oh my! (IMG:style_emoticons/default/blink.gif)

One last comment on the Electric Crossfire. I've seen this car before. REALLY nice job. Only one observation... It uses a Cursit controller!!! (IMG:style_emoticons/default/blink.gif) Wow. After all that work and they put probably the worst motor controller on the planet in there!!! I'm sure Otmar would have some words about this....

Thanks again everybody. I'm very confident I would not have gotten to this point without all the love here (IMG:style_emoticons/default/grouphug.gif) (IMG:style_emoticons/default/slap.gif) (IMG:style_emoticons/default/alfred.gif) (IMG:style_emoticons/default/beerchug.gif)

I'll keep ya posted when I get it back on the road. Probably this week if it's not something serious. (and I don't think it is)

[Otmar]

It uses a Cursit controller!!! blink.gif Wow. After all that work and they put probably the worst motor controller on the planet in there!!! I'm sure Otmar would have some words about this....

Sure, one of the reasons is that I refused to sell them controllers. (IMG:style_emoticons/default/laugh.gif) It's rare that I fire customers, but sometimes you have to.

As a experienced EV converter I could poke holes all over that design, but I will say it is pretty. (IMG:style_emoticons/default/smile.gif)
As for your intermittant problem Shannon, I'm assuming you have it set up in the normal Electro Automotive way where the main contactor clicks every time you hit the pedal. If that's the case then you probably need to check your Potbox and microswitch adjustment. It could be turning on the controller after the potbox has gone over 150 ohms. This would cause the controller to think your accelerator pedal is stuck on and therefore not allow you to drive...

Solution: Adjust the microswitch to switch on as early as possible when you push the accelerator, then adjust the pot on the shaft to give you 5K ohm as late as possible. Then verify that the microswitch clicks well before you hit 150 ohms on the pot. That should fix it, it's a common issue.
All measurements are with the pot unplugged from the controller.

hth,

[sgomes]

Um, WOW! Now THERE is some information I would have liked to hear about sooner! Thanks Otmar. (IMG:style_emoticons/default/pray.gif)

I've always wondered if everyone has the contactor click in every time you push the pedal. I'm assuming from your comment that you have yours closed as soon as you turn the key? I've always assumed this was a safety issue. I would much rather not have the contactor operating so much. Is there a safe way to have it closed all the time while the car is on?

[Otmar]

Hey Shannon,
Glad I could help out.

On the Zilla the contactor turns on when the key is turned to the Start position, and stays on until the Key is turned off.

But the Zilla also has two microcontrollers keeping watch on each other hundreds of times a second through an isolated interface. Either micro has the ability to shut down the car if something goes wrong. Other controllers don't do that.

If your Curtis were to fail in a full power on mode, your ability to shut off the main contactor is what will keep you running over the marching band in the parade, or the crowd in the crosswalk. (IMG:style_emoticons/default/ohmy.gif) Therefore it makes good sense to have it shut off if when you lift the throttle. Some people run the Curtis "always on" with only the key controlling the contactor, and it is nicer on the ears, but it also is a risk. It may take a long time for the driver to think of turning off the key in a emergency.

So those are the issues about it as I see them....
Experiment at your own risk.

[sgomes]

Weeeeellllllll... it isn't the potbox Otmar. (IMG:style_emoticons/default/sad.gif) I took it out of the car and put it on my bench at work. The arm isn't even in contact with the microswitch by the time it gets to 150 ohms. In fact after this is all done I'm thinking of adjusting it in the OTHER direction! The pot never made it to 5k!

So, back to the drawing board. I drove it around town a bit yesterday and it didn't cut out once. I don't know if I should be happy or sad. I'm going to drive it to work this morning so if anyone sees a yellow teener on the side of the road on 85 ..... (IMG:style_emoticons/default/rolleyes.gif) (IMG:style_emoticons/default/wavey.gif)

[sgomes]

I made it to work without any drop outs BUUUUUTTTTTTT just as I was rounding the last corner the contactor stuck closed. Lucky for me the controller was still listening to the potbox and the throttle didn't stick on. So, I guess I've narrowed down the problem. It's somewhere between the potbox and main contactor. WHEW! That means it ISN'T the controller (i.e. big kilobucks)! (IMG:style_emoticons/default/cool.gif)

[Otmar]

Have you got a snubber diode on the coil of your contactor?
It's possible you've burned the contacts of the microswitch, lack of a snubber diode on the contactor would make that happen pretty quick.

[bondo]

On my citicar I wired the contactor on with the key, but added a big red emergency stop button to the dashboard. Best of both worlds. Of course with the citicar the motor is weak enough that just leaving the parking brake on was enough to keep you from moving faster than a crawl, so I never really worried about it. On a more powerful car you NEED a way to stop it fast (IMG:style_emoticons/default/smile.gif) On the Cal Poly EV club's mazda, we have a big fat anderson connector with a lever that unplugs it. It's set up with two cables that pull the lever, one on the dash and one right in front of the windshield. We had to use it once, when the curse-it controller failed, and the contactor (unbeknownst to the current club members) was only rated for 48 volts. It tried to break 144v at high current and couldn't. The car went backwards about 10 feet (with the driver hard on the brakes) before someone caught up with it and pulled the cable.

[LongARM]

very nice story...
Thank You

(IMG:http://www.914world.com/bbs2/html/emoticons/drunk.gif)

[snflupigus]

I want to hear it go! (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif)

[sgomes]

Waiting for the rain to stop and for things to warm up enough to work on the car some more. Figured I should at least up date the ol' progress thread a bit. A LOT has happened since the last update.

Photos photos photos.....

First up. I made the BIG plunge and upgraded my controller to a Zilla!!!! For those of you who don't know, our non-club's non-member Otmar makes a living selling his own design. It comes in two parts: the Zilla controller and the Hairball brains.

The Zilla
(IMG:http://cafeelectric.com/products/pics/photos/IM0009.jpg)

The Hairball
(IMG:http://cafeelectric.com/products/pics/photos/HB2_640.JPG)

It's a sweet design and a massive upgrade from the crappy Curtis control(?)er. Pretty similar to going from a four to a six. Those who have seen Otmar at the dragstrip will understand.

[sgomes]

First thing to do was find the controller a better and DRYER place to live - the trunk!

The trunk was in bad shape. I don't have a good before picture but here is a colorful picture of what the whole trunk looked like:

[sgomes]

It was a multi-step process. The usual, grind, sand, clean, prep the surface (etch), rust converter (the red stuff), prime (the white), paint.

In progress:

[sgomes]

Prime.....

[sgomes]

Paint (IMG:http://www.914world.com/bbs2/html/emoticons/smilie_pokal.gif) (yellow is faster!)

Yes, it's a rattle can paint job. You pros, CWs, etc can kiss my (IMG:http://www.914world.com/bbs2/html/emoticons/bootyshake.gif)

[sgomes]

To mount the Hairball I needed to fab a couple of brackets. (IMG:http://www.914world.com/bbs2/html/emoticons/smash.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/sawzall-smiley.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/welder.gif)

[sgomes]

In place

[sgomes]

The Zilla got a donated heat sink to sit on. It fit perfectly!!!

[sgomes]

add some holes for the little wires....