Paul & Sabrina's cheap DIY 144v motor controller

[dcb]

lol, you don't even need the rest of the controller if you have one of those Not "cheap" though, by 8 bit standards.

CAN?!?

[regmeister]

i think it's amazing... guess I should get out more

did you check out the videos?

[dcb]

It's cool enough, about a palmtop there for $100ish, just seems an odd pairing with the humble (lol) cheap diy controller, this thread might be more appropriate forum for discussing it
http://ecomodder.com/forum/showthrea...tml#post136441 but it might be "underkill" there.

[Tweety]

Well... In terms of what that can achive it should be able to run the controler, the screen/touchscreen and a BMS without breaking a sweat, and then some...

I'm however more interested in the touchscreen which seems to be available on it's own... Hook that up to another Atmega and run a BMS along the lines of what the arduino can do and then hook it into the controller and you can have the functionallity of changing all the software settings on the road... Like what the RTD software can do...

Hmm... I'll go play...

[xtian999]

Got my kit. The soldering begins...

[Greg Fordyce]

Originally Posted by regmeister

Greg Fordyce posted a link to a BMS project.

It has a nice LCD implementation. I dunno if they're using a compatible microprocessor or not.

here's a utube

I am working on adapting the bms software to interface to the controller. The bms has it's own current sensor, so to keep things simple when I get a low cell I want the bms to adjust the max battery current value in the controller to a level that prevents the low cell warning. For example, if I get a warning at 200 amps, then set the max battery current to 180 amps. If 180 amps sets the warning then lower to 160 amps, etc. The bms will keep reducing all the way to 1 amp. Setting max battery amps to 0 disables the limit, so 1 amp is as low as we can go, and we won't be going very fast at 1 amp!


I can send data from the bms at up to 9600baud 8-N-1, but what would I need to send, say to set the limit at 200 amps? I don't need to read anything from the controller since the bms can measure current, just need to send it commands.

btw, the bms project started with a lcd display, but we are now using a SV2000 serial to video chip. This neat little chip takes serial data and displays it on a normal video display. You can find cheap 3.5 inch lcd displays on ebay, which is what we are using. The chip gives us a 16x9 character display but is a bit pricey. Recently I found a open source serial to video chip that has higher resolution and is cheaper.
Batsocks - TellyMate

Greg

[xtian999]

Assembly Question: Do you think it is alright to add a bit of flexible wire between the gate resistors and the control board to facilitate any future repairs? Seems like that would save bending or breaking the leads.

[adamj12b]

Normally that might not be the best idea, But the control boards pwm traces are not matched to begin with so it might not be a big deal.

To actually do that the best would be the end resistors wold be the shortest, and the 2 center resistors the longest so that the delay is evened out along the 10 resistors.

Might want to see what paul says.

-Adam

[xtian999]

Thank you. To be sure, I am talking about adding ten equal length wires and just leaving the gate resistors on the power side of the mounting board instead of pushing them through the holes. So, when I lift the controller board up away from the power section to fix something, all the resistor leads do not have to flex. I'm just looking down the road a bit to make things more service-friendly.

[Greg Fordyce]

...but what would I need to send, say to set the limit at 200 amps?

simply send the string "bat-amps-lim 200\r" where \r is carriage return (0x0d)

Fran

Thanks to the reply from Fran, sent to my email. My plan is to choose a value, probably 200 amps, to set bat-amps-lim when the first low cell warning is received and then start to decrement that value by 10 amps at a time until the warning goes off, or we get to 1 amp.

Greg