stuartpittaway
commented
3 years ago Hello Michael,
Good news for you, the next release of the diyBMS code contains most of the items you want resolving!
If you want to try it now, the code is here, you program it to the controller and modules just as you did when you first installed it. You will need to reprogram all the module ATTINY chips as well as this is a major change to the way things work under the covers. https://github.com/stuartpittaway/diyBMSv4Code/tree/modulepwmchanges
Hopefully I can answer the questions... I run an odd sized bank. I have 17S2P that I wish to monitor. How do I best do this?
Use the new code, it supports up to 100 modules, in a combination of up to 32S and 16 parallel banks. So 17S x2 strings (banks) will work fine.
I am getting some errors, and I am not sure why, it works mostly, hangs up sometimes.
The ESP chip can get bogged down with lots of web requests. The new code doesn't need the "upload filesystem image" option, which means that the new website is much quicker at loading. This should get rid of the problem you are seeing.
on my modules page I see many bad packets on some but not all modules heres a clip;
I don't know how many packets have gone through the system to indicate if this is bad or not, would expect a few bad packets every now and then, especially when balancing. Once a module generates a bad packet it will move through the others and they will record the error as well, so it looks worse than it really is.
Notice that the mass of errors around cell 0/9. What is the likely cause of this?
I would be tempted to check the module with the highest count. Possibly a bad solder joint or lose cable/JST connector.
How can I can the voltage RANGE on the main screen? Yes - its in the next version!
Also, could you add a rule that uses the temp Int? Yes - its in the next version!
Do the wires between the modules need to be twisted? If so how many twists per inch/cm? Yes - I've never actually measured the twists, they don't need to be super tight, I'd probably say 2 or 3 twists per inch.
Self powered controller? This is quite difficult to do as everyone has different voltage ranges on their cells. The easiest way to do this is with an external step down power supply/DC to DC converter.
What voltage reference chip did you end up using to replace the TL432? If it has a similar voltage (about 1.24V), then nothing needs to be changed.
Michaelillingby
I posted this on the open energy forum, not sure if it was supposed to go there or here. advise and I'll delete the wrong one.
Need a little help here with a few things; 1) I run an odd sized bank. I have 17S2P that I wish to monitor. How do I best do this? I currently have 17 modules hooked up and running, 0/0-1/0 and thats working just fine, sorta. How do I add my other 17S bank? Do I need to run a second loop with its own controller and IP address? Is there a possibility of changing the SERIAL BANK SIZE? like a drop down, or a text field 2) How can I can the voltage RANGE on the main screen? I run LiFePO4 and my MAX is 3.65vdc, so I would like the max voltage say 3.75vdc. The reason is that screen is not well used all being at the bottom. Is there some code that I can edit, or is this hard coded? and option on the settings screen would be nice. 3) I am getting some errors, and I am not sure why, it works mostly, hangs up sometimes. I can Leave a window open to the settings page in the background so I have access to the reset button, and that works most times. When I say hang up, I mean that the busy circle in the middle just keeps rotating and never fully loads. on my modules page I see many bad packets on some but not all modules heres a clip; Bad packet count
Bank Module Voltage V. Min V. Max Temp Int °C Temp Ext °C Bypass PWM Bad packet count 0 0 3.321 3.316 3.332 13 0 1 0 1 3.344 3.339 3.350 13 0 3 0 2 3.318 3.318 3.323 13 0 0 0 3 3.321 3.316 3.326 12 0 8 0 4 3.314 3.309 3.324 12 0 12 0 5 3.319 3.314 3.325 12 0 0 0 6 3.310 3.305 3.315 12 0 3 0 7 3.315 3.310 3.320 12 0 2 0 8 3.325 3.314 3.325 11 0 1 0 9 3.322 3.312 3.322 11 0 13 0 10 3.314 3.309 3.319 12 0 116 0 11 3.313 3.308 3.318 12 0 86 0 12 3.314 3.314 3.319 12 0 25 0 13 3.316 3.310 3.321 12 0 46 0 14 3.313 3.313 3.319 12 0 49 0 15 3.310 3.310 3.321 12 0 50 1 0 3.329 3.329 3.344 12 0 57
Notice that the mass of errors around cell 0/9. What is the likely cause of this?
4) Also, could you add a rule that uses the temp Int? This would be nice in addition to cell temp. Ie turn on a fan for high temp, or disable charging for cold cells etc.
5) Do the wires between the modules need to be twisted? If so how many twists per inch/cm?
6) Self powered controller? It there a possibility of including a small voltage reg to buck the pack voltage down to 5v? The other advantage is a controller based voltage sense.
One last thing, when I ordered my boards assembled, there were two parts they didn’t have, one was the attiny, and the other was the voltage ref I believe. I got a replacement ref from you when I ordered; Was i supposed to change any code when I swapped this v ref chip?
Thats all I have for now.
PS Stuart, I have exposed my esp via a port forward so you can poke around if need be, PM me for the link so you can see the errors I am getting. Due to no security on the webpage I won’t post this publicly.
Thanks in advance, Michael.