Looks like at their lowest point (this morning, right before the sun hit the panels) they were all within 0.1V of each other (one at 51.7V, other two at 51.8V). But the lowest SOC was on the Master inverter, which showed a battery low V of 51.8 (and I'm monitoring SOC, not V, FWIW). Also, all three inverters showed a battery voltage low alarm, which makes no sense because I have that set much lower, down in the mid-40s. No battery came even close to that according to the EG4 monitoring site, but I definitely see the warning from all three inverters, within about a minute of each other.
The other bizarre thing on the EG4 site is that on the "Monitor" tab, the only individual battery info I can see shows up only when I select the master inverter, and then I see only "Battery 4". No other batteries appear. On that, Min cell is currently at 3.338V, max is at 3.342V. And it shows a 42% SOC while I'm seeing 57% for the overall pack SOC. But I can't see any of the other batteries individually.
To make things even weirder, the battery info on the right of the screen on the Monitor tab gives me info only when the Master inverter is selected in the dropdown box, and then it shows only the info for ONE battery (280AH) and a "Total Battery" count of 1 (when I have five, for a total capacity of 1400AH). But when I look at the EG4 app on my phone (which presumably pulls data from the same source as the monitor website) it clearly shows that I have 5 batteries in parallel, with 1400 AH of battery capacity. So, yeah...... Makes no sense to me.
Overall I've been very happy with this system, but it seems like something is definitely wrong with the reporting metrics. I think I'm out of the danger zone, but frankly I'm not convinced EG4's info is accurate, at least once one gets past three batteries. And I know that I'd very much like to know the SOC of my lowest battery, not just the overall pack SOC (which I find only borderline helpful). Perhaps
@EG4TechSolutionsTeam can provide more insight. If helpful, I'm happy to get on a call with them.