Dahli 16S 200ah with UART and BT.
Learned another hard one today. You can make lots of changes to these BMS's while they are active with no issues. But there is one or two that may damage equipment if you play with them while your solar system is active. After damaging the USB to UART cable I spent a couple hours figuring out what happened.
My XW Pro was putting out about 2,000 watts AC while pulling power through the Dahli BMS. I was tinkering and I needed to adjust "Cell Volt Low" setting using their PC software "PC Master". I adjusted it from 3.05 down to 2.8 giving my inverter and charge controller more of an opportunity to shut down if needed first rather than the BMS. You don't want your BMS to shut down for any reason if possible while your charge controller or inverter are under load. The moment I pressed the Set Icon the inverter shut down. I retraced all my steps even though my actual battery was at 18% SOC while under load I still had about a 6% margin. Well sure enough the abrupt disconnect of the battery while active use ruined the USB to UART cable instantly.
Fortunately I had another one but then I was very concerned about doing it again while trying to figure out what happened. So I wanted to as such make my own from things I had laying around and if it was isolated all the better.
DIY USB to UART if you burn up the one like I did.
I used a Waveshare which has isolation.
USB to RS232/485/TTL
You can find them on Amazon and they don't cost that much. After an hour of testing with some Com apps here is what I found that works perfect.
Set the com port on your Windows machine for this Waveshare device to 9600, N, 8, 1.
Use the TTL port, not the RS485 port.
Open the app, select the port, then open it. If it doesn't work you may have to reverse the send receive wires.
Now if this happens again at least I will not damage my USB to UART hopefully because I have isolation.
Now I really need to figure out how to go from TTL to wireless or hardwire ethernet without Arduino or Raspberry. In other words plug and play remote access via the web for these BMS's. I will start on that in a few days. All ears if you guys have any ideas.
Some pics:
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The cable I used to hook this up was cut off the one I burned up so you can see the color code for both pieces of equipment.
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The original that I cooked before cutting off the USB side
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And something that makes haste of balancing new battery packs. Heltec 24S 5 amp active balancer with BT and RS485. Ultra simple to operate and you don't have to spend days top balancing high ah batt packs.