Thank you so much for your attention, i am thinking about using two signals bms, i completely sure that it works in order to protect when one cell is under voltage or over voltage, but not for disabling charger when the battery is full, because we config diybms using a voltage value, so when the multiplus goes to absorption( using the same value of absorption stage), diybms thinks the battery is full, however to protect the over and under voltage is perfect. What do you think about it.? Thanks in advance
Not sure what you mean. diyBMS has 4 things you can use. Cell over and under voltage. Pack over and under voltage. All of these control the charger BUT that is only for protection since itâs the charger that should control the charging cycle.
I run LiFePo4 and unless your cells are very old and unstable you dont need more than 1 per cell and those 310Ah. In my case i run 360Ah per 1A balance current and have no issues to balance it. I would start with that 
With latest code you can see how much time/energy you have dissipated during balance.
It will work fine. I run a 100kWh bank with a system like this. Not DIYBms yet but will be moved to it in short
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Im not following what you strive for either. As said by Donnib you have a set of triggers you can use. Are you asking for another type of trigger that you want to have integrated?
I actually do want some more rules 
, I made a issues about it some time ago More rules for different voltages · Issue #99 · stuartpittaway/diyBMSv4Code · GitHub
Ah ok. What you look for is whats generally called âlimit chargeâ or something like that. A function that can reduce charging so that balancing can catch up. Even though it can made with rules as such and its rather simple to add another rule its often better to use RS458 or canbus depending on inverter and instead talk to the inverter. Though this require alot more coding.
Im currently using an ESP8266 that sits in between doing that kind of job in my system. Ie i have attached an ESP8266 on each of my device that talks MQTT and then is controlled. Yes it makes it more vulnerable adding more devices but for me thats not a critical function.
I recommend to set up the variables on your charger/load so they always can work without it and in case of issues the rules kick in and shut down
well not really i mean this is not what the issue was about however that would be nice as well and yes i agree that should happen over modbus or can, maybe we will get that in the new controller.
My issue is to have a double mechanism. For example, when should the main breaker trip ? I would like one more set of the under/over voltage rules with other voltages set that will trip the CB because that should be last resort if something goes waywire and in that case i trip the CB and i have to activate manually.
Ok @donnib then im not following and i feel a bit dumb 
But lets say you have 2 rues for overvoltage on cell level. What would
Rule 1 do?
Rule 2 do?
So i can understand what those 2 rules would do in your case
Hi gentleman, do you encounter this kind of component shortage problem? Mine since January for D1 component through JLCPCB and LCSC. Any solution or optional other component recommended would be appreciate. Thanks.
Rule 1: switch charger to float or disable charger until rule resets
Rule 2: trip the circuit breaker
In other words if Rule 1 fails e.g the voltage raises further to Rule 2 level then something went wrong with the inverter since it keeps on charging even though we told it not to so we activate Rule 2 meaning we pull the plug.
Does it make more sense now ?
See this
It does. But for me you should either set the values better on the Charger so you dont need it or it should be a limit function. Based general how bms systems work.
gracias
Thanks for info.
Maybe someone can help me with avrdude. Iâve got avrdude installed and Iâve copied the new avrdude.conf file from stuartâs link. But there is no part t841 in it. There is t84, but not 841.
Are you using the latest BOM and v4.40 design?
Iâm just discover the new version of circuit after watch your youtube vid. Sorry my bad.
Anyway, thanks mr stuart for the great design youâve made, appreciate most.
Yes thatâs fine, are you ordering the v4.40 boards?