My setup is simple. I have a Multiplus 2 GX 5000VA that has the grid on the AC input 1. The grid is a 3 x 230V without N. All single phase loads are on the AC output 1. My AC coupled PV inverter is also on the AC output 1. In passthrough mode everything works fine. On the grid side there is a EM540 that measures the 3 phases for the multiplus.
Now I have a battery attached with a smart shunt as monitor connected to the multiplus on VE.Direct. It doesn’t matter what I try I just cannot get the battery to discharge for my loads. It charges and then gets stuck in float without discharging.
Any suggestions what I can check or try to get this to work?
Can you make us a drawing of how you operate the Multi on a 3x230V Grid with a meter … and all this without an N conductor? did you use the PE (Earth/Ground)
Is the system again in Belgium?
I configured the ess assistant but that didn’t do anything. So I went a step back and removed the ESS assitant and tried to operate in offgrid modus so with the input breaker switched off but my battery didn’t take over.
If the inverters are physically switch on and on the GX…
Does the system switch off?
If inverting does not happen, there is something between the battery and inverter system that is preventing it from happening such as a fuse blown or batteries tripping.
You will definitely need the ESS Assistant to unload your system to the Grid.
Please give us a few screenshots of your config and the Remote Console.
What is strange, however, is that your system does not work OFF-Grid, i.e. only as an inverter.
If a voltage is present, the Multi MUST work as an inverter. The shunt has no effect on this, except for the measurements. The only thing would be undervoltage shutdowns.
Does your BMS release the voltages and currents?
Do you have an app or displays from your battery here?
The multiplus did not switch off but the whole AC output 1 went down. My inverter was still inverting but sensed that the ‘grid’ (AC output 1) was not there and did what it had to and switch off. But the multiplus did not start inverting. There is no fuse that is blown on the battery and the BMS still says it’s ready to charge/discharge.
Sustain and Cuttoff Voltages in the ESS maybe much to high
What Kind of Batterie do you have … and Communikation via BMS CAN ? … Batterie monitor in the Remote Console ?
Are you already using the (5000W) inverters on the AC Out or have the values only been entered for the time being?
It’s a 16S lifepo4 battery. I think I left those values on default. The PV inverter on the AC out is a 5000W inverter and is in use. But only rarely reaches the 5000W for long periods of time. The BMS does not have communcation to the Multiplus.
What kind of loads have you connected to the Multi and how is your system set up?
If a DC voltage is connected, the Multi should automatically go into inverter mode.
Maybe a Screenshot of the Remote Console / Main Overview
A bit embarrissing but this was the solution. I remember reading about the “I” position of the main switch. Somehow I must have put it on “II”. This solved all my issues. Discharging/charging in offgrid modus works. I enabled DESS again and everything works as it should.
