Odd readings from Daly BMS

[rogerball0]

I hope someone can help. I originally thought i had a duff cell in my pack, (280Ah battery using a Daly 4S 150A BMS). The blue tooth app shows three of the cells at 3.47 V give or take 0.002v but cell1 is reading 3.265v (0.2v differential).

I immediately opened the battery box and put the multi meter across each cell and they all record 3.47 V, I even unplugged the five pin balance lead plug that plugs into the BMS and put the meter on each pin of the plug as per Daly's instructions when setting up the BMS and again got the same (3.47v) across all 4 cells so i know the balance leads are good.

Why would the BMS give such a different number on the app, is there a way to reset the BMS back to factory settings and see if that works? Have tried different cells on the same BMS and get the same problem so i know the cells are good and think its the BMS.

Is there a chance the cell with the duff reading could get damaged by overcharging?

Any help greatly appreciated

Roger (UK)

 

[Rotgut]

Hi. I have two Daly 4S 100A "Smart BMS" units that show incorrect voltages on the cells. The BMS shuts down power because it thinks one of the cells has low voltage, but in fact it doesn't. I have done all the "standard" things to check - checked cell voltages with a voltmeter, changed the voltage measuring wires, switched cells around, reconnected the cells in parallel and left them overnight. The problem is only resolved when I exchange the BMS unit. When I restart these BMS's they sometimes change the cells reading high and low. I have put both faulty Daly BMS units on the shelf for now and am using "dumb" BMS's. They are running fine while I wait for my SL-03 solar charge regulators (with built-in LiFePO4 battery management). If these are not up to the job, I will swap to a different type of BMS as the Dalys have not been reliable for me.