So any constructive assistance will be highly appreciated. I have researched this fault numerous times now and also looked across many forums, but I seem to not be able to diagnose and correct these errors.
Background: I have a Multi 2 5000 connected to Cerbo GX with 250/100 MPPT and BMV 702 connected to a 120Ah lithium bank that has its own BMS (so a dumb lithium essentially).
Problem 1: If anything happens to the Multi and I have to restart of switch off or update ESS settings on VE Config I cannot get the Multi to accept AC input voltage. It reads the voltage and displays a nice 233V on AC-in L1 but Active AC Input shows Disconnected. When i turn on the system it goes through the following steps:
I switch the switch to position 1 and soon after the Inverter On comes on and then one hears a internal relay switching a few times. Then after 30 seconds or so there is a loudish click and inverter switches off, after a minute it switches on and process repeats. Eventually it stays on but Main On does not come on and I have no AC input to the system.
This is now the 4th time this is happening to me and it seems to have come right on its own somehow the last few times. I suspected corrupted firmware and reloaded it via VE Config the last time and when I looked again it was working. Co-incidentally the problem occurred while I was downloading the VE Config file to make some charge voltage changes (this coincidence is just too big)
What info do I need to post here to clarify this issue?
Problem 2: Every day I get a high voltage alarm on my BMV. Also I noticed the alarm when I was busy trying to restart my system from the AC input issue.
My settings are as follows:
BMV (Battery)
Capacity 120Ah
Charged Voltage new 56.8V (old 57.6V) (3.5625V/cell) {58.4V (3.65V/cell)}
Discharge Floor 10%
Tail Current 4%
Charged Detection time 3m
Peukert 1.05
Efficiency 0.99
Current Threshold 0.10 A
Time to go averaging 3m
MPPT (Battery)
Voltage 48V
Max charge 70A
Charge Voltages:
Absorption new 56.8 V (old 57.6 V)
Float 56.8 V (old 54 V)
Equalization 55.2 V (Old 54.4 V)
Auto Equal Disabled
Temp Compensation -64.80 mV/°C
Cerbo (VRM Online)
Multiplus Remote VE Config File
General:
AC input limit 50 A
tick Enable battery monitor
State of charge when bulk finished 95.0 %
Battery Capacity 120 Ah
Charge Efficiency 0.95
Inverter:
Output Voltage 230 V
DC input shutdown 45.0 V
DC input low restart 50.0 V (Old 51 V)
DC input low pre alarm 45.5 V
Charger:
tick Enable charger
untick Weak AC input
tick Lithium batteries
Charge curve [Fixed]
Absorb Voltage 56.8 V (Old 57.6 V)
Float 56.8 V (Old 54 V)
Charge Current 30 A
