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Need a little help here with a few things

Hardware diyBMS
#1

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?

  2. How can I can the volatge RANGE on the maiin 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?

  1. 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.

  2. Do the wires between the modules need to be twisted? If so how many twists per inch/cm?

  3. 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.

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.

DIYBMS v4
#2
  1. 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?
#3

the voltage reference indicated by Stuart is the code C171428 which is usually missing.
I also got most of the modules without this component and I successfully replaced it with an equivalent of LCSC C84139 Mfr. #: AZ432ANTR-E1 LOW VOLTAGE (1.25V) ADJUSTABLE PRECISION SHUNT REGULATOR.

If you replaced them with a LOW VOLTAGE (1.25V) ADJUSTABLE PRECISION SHUNT REGULATOR. You should not have problems, the voltage value is different, the measurements will be wrong.

#4

I’ve replied to the message over on github.