I have a BMV712 connected to 4 x 220AH Victron Gel batteries in series, an MP2 3kVA and a 150/45 MPPT using ESS.
I put the bmv in when it became obvious that the MP2 was useless at accurately reporting SOC.
I have tuned the BMV as per docs and some guidance from victron (charge voltage midway between float and absorption, extended the time needed to sync to 8 minutes and reduced the tail current to 1.9%).
This works most of the time, the SOC gets to around 98% and then syncs.
Where it falls apart is if when there are bad PV days and the charge voltage is closer to float, the batteries don't sync. after a couple of days you end up with charged batteries but with a decreasing SOC reported.
When batteries discharge you now hit the ESS SOC limit too quickly (only use top 30%) which means the batteries never discharge far enough to hit bulk/absorption.
You're now get stuck in this float/discharge cycle, with battersafe increasing limits making it worse.
Being unable to force a remote sync means it is a real problem to break this cycle without having to start changing the ESS schedules and limits.
Is there a better way to setup the BMV?
For those doing partial discharge of batteries it isn't difficult to end up in this loop.
