Paul & Sabrina's cheap DIY 144v motor controller

[esoneson]

Originally Posted by MPaulHolmes

...........but a rather strange set of circumstances happened. .........

Nothing strange about helping your fellow-man in time of need. You and Sabrina have hearts of gold. Good luck to your friend. Hey, maybe you could employ her to assemble controllers?

Good going mate!

Eric

[sawickm]

Hi All,

Friday I ordered a complete kit for the Power PCB, and was also told by Digikey that the MOSFET's would not be shipped out to me until the beginning of January 2010 too.

I am donating a Power PCB kit to Adam for him to test out his new heatsink mounted Power PCB layout design.

I used the same source for the MOSFET’s (IRFP4668PBF) that Paul recommended which did have them in-stock. It was the manufacture “International Rectifier” through their online store. The cost of the MOSFETS was $6.00 each plus a shipping & handling fee.

I will also look for direct replacement MOSFET’s and Diodes parts that are pin compatible with the existing parts. I will post them if and when I find them. IXYS Corp. manufactures alot of MOSFET which my work, and are also availibe through Digikey.

-Mark

[mike_lera]

Hi all
have been lurking in the backround and decided to give it a try.
on the wiki there is x y plot for the power board but there are no z moves
is there some one that has the g-code put together that is in a text format that can be loaded to the wiki?
PAUL THANKS FOR YOUR HARD WORK

MIKE

[adamj12b]

OK, I added the Gcode files as well as the CAD files that I created to the FAB Files page of the wiki.

The Gcode files were posted for Mach3 controller. The tools needed are a 2.5mm drill bit, a 1/16" drill bit and a 1/8" v-point etching/milling bit. the larger holes for the buss bars and the heat-spreader are milled with the 1/8" bit.

-Adam

[montgoss]

Originally Posted by MPaulHolmes

Hey Don, that's exactly what Fran had just suggested to me about the throttle. He also said that it is often a problem when it goes below 0v. Hmm... The throttle pot is far away from the rest, and the wires are really long that could be picking up noise.

This was a long time ago, but I finally got through the whole thread and don't think this has been fully addressed...

Is it just the atmega8 that has issues with locking up the processor if the voltage goes below 0v or above 5v? Or is it all the Atmel chips? Something that causes a lockup such that the watchdog doesn't even trip concerns me.

A solution/workaround and something I was thinking about regardless of the lockup issue: add an i2c bus. With that, we could put any number of adc's on the bus (should someone want to monitor many things, like each individual battery voltages perhaps). And we wouldn't have to worry if the inputs to those chips went outside the range of the processor. We could have simple error checking on the return values of those chips and there would be no possibility of a noisy throttle line or whatever causing a lock-up. And they'd most likely be more accurate than the built-in adc's of the atmega8.

I looked at prices a little. Looks like they're a couple of dollars a piece. So, it's probably not something the ultra-low-end builders will want. But I might like some on my version... And obviously the prices go down quite a bit when buying in bulk...

Edit:
I did find the TI ADS7828, which is a 8 channel ADC for $6.66 from mouser. You can have up to four of these chips on an i2c bus, allowing a total of 32 ADC options. I think one of these chips is going to be much better bang-for-the-buck than several 1 channel ADC's.

[niksgarage]

Originally Posted by montgoss

This was a long time ago, but I finally got through the whole thread and don't think this has been fully addressed...

Is it just the atmega8 that has issues with locking up the processor if the voltage goes below 0v or above 5v? Or is it all the Atmel chips? Something that causes a lockup such that the watchdog doesn't even trip concerns me ...

I think this sounds like generic CMOS latchup - it affects many VLSI circuits. Sometimes the solution is as simple as looping the wires through a ferrite ring on their way from controller to PCB (close to the PCB). By all means protect the inputs with small caps to ground, and reverse biassed diodes to the power rails as well.

[vince]

Hi Paul;As one of the many ev'ers who don't understand a word about what your talking about but are waiting to build one of your controllers, could you share in simple english how it's coming along?Thanks,vince.

[MPaulHolmes]

Hey Vince, I'm filling in the gaps of a help document right now. Also, I just got my mill converted to CNC. That was really fun. I'm not lying. OK, maybe not "fun". Actually super annoying trying to get everything centered with using a hand drill for making all the holes.

As for CMOS latchup, it hasn't been a problem for Joe running it at 16 Mhz. I've been told that it's often a relatively easy thing to deal with if it were a problem. Since it's not happening, I am not trying to actively fix it. I am learning how to do my own layouts, and I was going to add a couple schottky diodes to protect from spikes in the throttle input in the next version, even though it's not really a problem right now, just to be safe.

I'm also doing a set of gcode files that will be 500 lines or less each, so people can use the free version of Mach 3 if they need to. My gcode will have one more bit change than Adam's, but that's not the end of the world. Also, I've modified the etching a bit for less surface mounting.

My wife set up an online store for our website for anyone that doesn't want to do the precision drilling, ordering of parts from digikey and mouser, etching, ordering control board from a pcb house, etc... We plan on using any money we make to invest in alternate designs and we are trying to get our daughter here from Kenya. She had just gotten off the streets when we met her when we lived there in 2006-2007. It's funny, she always wanted to be a hair dresser/aeronautical engineer/pilot/professional singer/dancer. Once she gets here, any funds made from controller sales would likely go to her recording studio time. hahaha. We had to bring Michael back to Mother Teresa's before coming back to the U.S. because of international adoption law changes (the Hague Laws). All very stupid and unbeneficial to him.


Sabrina set up 2 types of kits. A kit for the soldering impaired and one for people that just want to put everything together themselves. For the do it all yourself kit, all the tools that will be needed will be a wrench, screwdriver, 200 watt soldering gun, and regular soldering iron. For the less adventurous, there is a kit that is quite a bit quicker to put together. You only need a 30 watt soldering iron for that one, and there are only 12 little spots to solder. Maybe we should add a completed controller too.
Here's a link if anyone wanted to see it:
Paul & Sabrina's EV Stuff!

Sorry for the cost, but it's a lot of work. The good news is I believe it's better than a Curtis 1231c.

[vince]

Hi Paul;Happy looking kids.Thanks for getting back to me.I live in Ontario,Canada,just up the road from you.I really appreciate all you and sabrina are doing and I'm sure you will receive tenfold.I always have my eye on this site,thanks again,vince

[sawickm]

Hi Paul,

Thank you for posting information about your EV Motor Controller Kits.

I see that you sell the bare Controller and Power PCB's at your website’s Other Components.

My question is could you also add a pre-programmed AVR micro controller as a product you would sell ??? I don’t want the hassle buying a programmer and go through the whole process of programming it, I would rather just buy it from you ?

-Mark