This first picture is the bottom of the Home page shown in post #80. My original Eco-Worthy app didn't have any "history" information on the various faults. The Overkill app has a section that shows you what has happened. It is very interesting because the most common fault when setting up is a cell overvoltage shutdown because the battery isn't balanced yet. The "Alarm" area shown in post 80 indicates (in red) that a fault has occurred. The charge current is turned off and the cell voltages drop while some balancing goes on. After maybe as short as 5 seconds, the overvoltage cell has dropped to the point that current is turned back on and, if not watching, you've missed it. I watched this type of cycling go on for +10 minutes and 30 "alarms" shown in the picture at "single cell overvoltage" times in the picture below (I had erased them before taking this picture.) Without the history provided by the Overkill app, I would not know that this battery had gone through a rather lengthy balancing act.
Here is a screenshot of the first part of the Settings page. Unlike the picture shown in post #81, this one has the data showing. It appears that I could make up my own parameters for what constitutes 100%, 80%, etc. Don't know why I would. What interested me is the next category down, Balancer Configuration.
The Overkill app allows the user to define at what point the balancing will start. I set it at 3300mV (3.3V per cell). The delta between cells is set at 15mV (.015V difference between cells). After watching my worst balanced cell, I can generalize that my cell imbalance doesn't really begin until rising above 3.4V per cell and I don't know if an "early start" on the balancing at 3.3V actually helps (nor if starting to balance at a .010V delta would do anything.)
The default setting was Balancer Enabled, but "Balance only when charging" (the second slide button). I changed that and watched what happened when a cell hit the overvoltage alarm and turned off the charging to all cells. When charging is shut off and the cells are in the 3.4-3.6V area, the voltages naturally drift down. But with "Bal. only when charging" switched off, that actually means balance while charging
and while not charging. Again, this was only for a few moments and then the parameters allowed charging to resume.
As for the possibility of a cell overcharge shutting down a battery while being charged with an alternator, and thereby damaging the alternator, there are a couple of considerations. First, I only have one battery that is going through this balancing phase. The other BMSs have remained open and receiving current. Second, the overbalance occurs only at the very end of the charging cycle. Post #80 shows my "problem" battery (#3) accepting 16 amps with balancing already begun and not even close to a cell overvoltage (3.65V). At this point, all 4 batteries are basically accepting the same current (about 75 amps total). By the time battery #3 begins cycling through any overvoltage shut downs, the acceptance current is down around 5 amps, which might be below that needed to create a damaging spike. Third, none of the other batteries have shown any tendency to be out of balance or shut down. Forth, just in case, I installed a Sterling Alternator Protection Device to absorb any voltage spikes should a simultaneous shutdown of 4 BMSs occur while charging with the alternator. Most of my testing so far has been using my shore power charger which is unphased by all four batteries shutting down (I did a nervous Nelly test).
At the bottom of the page above is Function Configuration with two slide buttons. The first is "SW switch circuit enable". Near as I can tell, this disables the Charge and Discharge slide buttons on the Home page. Weird. The next button is "Display Celsius," which changes everything to Fahrenheit. I did that.
Here is page #2 in Settings.
Of note here is the setting for "cell over voltage." I have read in many different places that one shouldn't charge LFP cells in excess of 3.65V (3650mV). The stock Eco-Worthy setting was for a cell over voltage of 3.75V for a period of 2 seconds. When I first got my Eco-Worthy batteries and was charging them for the first time in the garage, I saw Battery #3 reach a single cell overcharge of 3.75V and thought that was odd. Now I know why. I dialed that back on all batteries to 3.65V. I suppose one might get a longer balancing period by letting the outlying single cell go to 3.75V, but I'm not convinced that's a good idea.
Next are the Level 2 Protections. Oddly, these settings were not uniform on the batteries. Nor did they really reflect any of the parameters given in the Owner's Manual or the online information. The same is true for the Level 3 Protections. Nowhere in the Eco-Worthy literature is an amperage rating given in milliseconds or microseconds ("us" i.e., one millionth of a second).
Following that are the temperature sensors, which on this battery, are three. Another weirdness.
In addition to the 250A breakers for each LFP bank, the only other gadget I added was the Sterling Alternator Protection Device. I already had a Balmar ARS-5 external regulator. It was fairly easy to set it to the LFP charging parameters that I wanted. So far, even with Battery #3 doing its balancing act, the entire bank easily reaches the charging parameter of 14.4V and drops down to the sustain value of 13.3V.
Mark