Hi, those two indicators show the highest and lowest voltage for that module over time (since last controller reset). The current voltage is show by the bar chart
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not able to download, can you please upload again?
Welcome, @VisionQuest.
What is your problem? I can see and open the attachment to the August 17th post, with no problem. Have you checked your end?
my bad, working now. 
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Hey folks have been looking at this bms for awhile, does anyone manufacture these boards?
what does the current bom run for?
Hello Stuart (or anyone who can help/answer),
First let me say thank you for putting this together for the open source/diy community. A coworker and I were looking into using your BMS setup and wanted to confirm something in here first. Without the relays is there any sort of over voltage or under voltage protection built in? If not do you have an approximate time on when you might be able to add some information or a video on how to add the relays to the controller board? Lastly I believe going off of the board you are looking to add overcurrent protection as well, about how far off into the future is that?
P.S. I completely understand that you do this as a side project in your free time so nothing is really set in stone, just a ball park answer for any time frames as I would prefer to have some protections for my battery investment in place.
Hi All!
I want make this BMS, but my english is very basic and I canāt to read the full topic. I have some questions. All questions apply v 4
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This BMS is active or passive? ( energy transfer higher cells to lower cels, or discharge higher cells )
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This BMS can managing 14S pack?
Thanks.
I believe relays work now, Stuart did a video about this on his youtube channel. Theres a little 6 pin header on the controller board which connects into a āstandard ebay specialā relay board
Hi, discharges higher cells, iām building a system for my 14s pack which I believe should work. I think it goes upto 16sā¦
Is there any chance of cross talk over the serial connections? While Iāve not gone looking for a fix to the proble, Iām having random BMS systems appear to crash. Normally the first few closest to the TX port of the controller.
The issue is obvious due to the green LED on the BMS staying on and the comms flicker of the other BMSās go into āsolo modeā. Also the webpage monitor reports loss of comms to the BMS modules.
Disconnecting the BMS from itās cell and reconnecting fixes this. While a BMS is in this āerrorā state the controller has problems talking to any BMS. This appears randomly time wise, but usually at the end of the BMSās closer to the TX port of the controller.
I did move the connecting cables away from the other BMSā, controller and any other interference, but Itās a long distance from any AC, or higher DC voltages apart from the battery itās self. And this is only a 7s.
Iāve changed controller to no avail.
The reason I ask about cross talk etc is because my jumping cables (between BMSās) are longer then are needed. Iāve been planning to shorten then eventually, but if this isnāt an issueā¦
Iāll post a pic later.
The serial protocol has a CRC check in it to prevent issues with corrupt packets being received.
That been said, I have also experienced the issue you mentioned but thatās normally when Iām randomly unplugging and reconnecting the modules, sometimes one needs a nudge!
Thinking this is a code error rather than hardware issue.
Thanks for that info Stuart. Mine have been connected for a couple of weeks feeding data to influxdb if passing you the log would be of any use?
Sorry for the late reply, yes indeed I did see him using the relays which is how I found out about them. Being a little new to this kind of stuff though without some detailed instructions its kind of hard to piece together exactly how things are happening. Thanks for reaching out in reply to my question. Perhaps if you go get this system up and running you could make a video showing how you assembled the control board as well as the relay board.
Hello ALL
I just wondering before i start trying to do this i thought i ask if someone has tried it already.
I tried to make 20 V3 boards and wasnt that successful to be honest biggest headache.
I know only have 8 boards out the 20 working, did have 16 working and provisioning. Anyway i was going to try and make V4 but i want to make it with Through hole components if possible. Has anyone tried this. If so love to chat and if possible get copy of the pcb and BOM fiies. Thanks Andy
Why not use the current board package, itās not as difficult as you think. There is a video couples of post up about the making of the bms
Ufumoa is right. People have hand soldered them. One guy did it while in a truck stop over night.
Heck I tried it for the lols, but did the rest with a heatgun. But it is possible. Re-engineering the boards for thru-hole is just a waste of time that you could be spending on soldering the normal SMD boards.
If you want to avoid the soldering, just ask the PCB company to assemble the board for you - it will cost more but you will get a working board without the hassle.
Adny, Check your PMās
Hi, Andy,
I have the same problem. Already soldered 5 ESPController and 5 ATTINYCellmodules, they are blinking, Cellmodule every 8 seconds, the other module every 4 seconds. But I canāt get any connection in between the modules. Debugging shows, that the ESP 8266 is working, just doesnāt get any data. But I have to say, that this is my first SMD soldering project. So I continue trying to get better and better in soldering 
Maybe the professionals here have some advices for beginners? Are there any other ways to debug the modules?
For example on the ATTINYCellmodules I have 4V at the RX1 and 240mV at the TX1. Is this ok?
5 controllers ??
Are you referring to v4 boards here? Just connect a single controller and a single module together (donāt forget you need 2 cables for this for form a loop).
When soldering the critical part is not to solder the 2 pins of the opto-isolator together - this would be very bad 
Take a look at my frying pan soldering techique for the v3 boards - same applies to v4
