Paul & Sabrina's cheap DIY 144v motor controller

[billhac]

well Ill be glad to help with the cost of the first boards, so it around 350 bucks all together? when i get paid again on the 10th I could manage some of that.

[flores]

Paul.. no problem.. all for the good cause.. I've been reading the whole thread.. so I know the deal.. there is no guarantee what so ever... I could die testing the controller.. I know.. makes me want it MORE..

How would the total sum add up with all the parts?

[MPaulHolmes]

Originally Posted by flores

I could die testing the controller.. I know.. makes me want it MORE..

ROFL

I'll figure out the total cost. I have some good news! I am in Ubuntu and I can see what I'm typing!!!!!! I installed a whole new version of it. I think it's "stinky susan" or something like that. Man they have weird words for the version names.
I Like Linux again! HUrray! I apologise for the words I said in anger, and I apologise for the penguin I ate for dinner last night. I'll figure out how much I can pay of the setup fees.

[DJBecker]

Originally Posted by shortcircuit

I've been looking/working with the OSMC (open source motor controller) for my mothers mobility scooter.... and I need a controller circuit that will take the analog signals and convert to PWM that OSMC will understand.

You'll likely find the Arduino hardware easier to start with.

The Arduino boards use the Atmel ATMega AVR processor family, the same type as the Cougar. You won't need most of the hardware on the Cougar board, and the Cougar firmware will run on any of the Arduino boards with only a few minor changes.

The bonus is that there are many plug-in "shield" and "module" boards for Arduino cards, so you can often do projects just plugging them in rather than doing modules.

[billhac]

just finished ordering all the power board components for revolt #2, the one thing I hate the most is having to wait for the stuff to come in the mail, I allways pay for expedited shipping because I want it yesterday and not tomorrow. haha darn mail man hope he gets bit by a dog!

[MPaulHolmes]

Don't tell the mailman that! Those guys are crazy! Always shooting up convenience stores and what not. I used to work at the post office picking up the mail from the blue boxes everywhere, and those supervisors are insane. That's what drives the regular mailmen to acts of drunken violence.

Another unknown I was thinking about is, should I use a copper heatspreader? How about 1" instead of 0.75" wide heatspreader? hmm.... Should we just pick a cost, and order parts based around that? How high end should it be? Some performance variables that I see are:

heat spreader copper vs. aluminum. heatspreader 0.75" wide vs 1" wide. Lowest end price: $9 for 3/4"x1.5"x11.25" aluminum
Highest End price: $60 for 1"x1.5"x11.25" copper

capacitance of DC link film capacitors
Lowest end price: $21 for 10 2uF caps.
Highest End price: $54 for 10 12uF caps. Assuming I order 30 of them, for 3 beta testers.

[billhac]

well the couar controller did use a copper heat spreader, but im of the mind if it works don't fix it, now if you are talking about your 1000amp version then more mosfets= more current=more heat, then copper might be better for it, as a kit like the 500amp one is i would not mind buying copper over aluminum, because thought it costs more I could spread the cost out if i need to like fets and diodes one week, caps base plate another week, heat spreader and bus bars another week, then it takes a while but it dont hurt as much. at least for a working guy like me.Im also of the mind that more power is more better so i cant wait, no really I cant oh man still waiting just my .02

[flores]

Paul, I would be great if it works the cheap way..

The only way to find out is to try it I guess. Unless you are almost absloutely sure the cheap solution is very likely to fail.

[MPaulHolmes]

I only used a copper heat spreader on Joe's I think. And maybe Adrian's. Perhaps aluminum is just fine? I haven't heard of any thermal problems from anyone. I just don't know what the difference in performance is. I'm inclined to think that aluminum is fine for most people. Bill is in Phoenix, Arizona which is another name for the fires of heck! I'm sorry for that terrible language! The only part that determines the power board is 1" or 0.75" wide.

[flores]

Even if you make the heatspeader out of copper, the base plate will still be aluminum, right? If that's true I'd say that aluminum is fine for the heatspreader. The system has to lose the heat through the base plate anyway..

Or is that an all to simple conclusion?