question

@lucadea1985@gmail.com

In properly configured system BMS should never intervene i system rutine operation.

BMS intervenes only when there is something wrong with the battery.

To answer the other question we need a diagram of your system with complete technical information on all components.

thanks for your help. The BMS is connected via can bus and sends to the victron the state of charge at 100% to stop charging, it does not cut the power to the battery. how could you do otherwise?

Screenshot_20220522-123730.jpg

at this moment i am charging the battery with 20A as set in the DVCC, the ftv connected on the victron could produce about 1500watt at this moment but it is reduced to 1000 due to the DVCC. the 361 watts of load are taken by the fronius but could be taken by the victron mppt by feeding all the 2111 watts produced by the fronius into the grid

@lucadea1985@gmail.com

Do I understand it right that you do not have any load connected to AC-out of your EasySolar?

What is the purpose of this system?

Do you have ESS assistant loaded?

The standard setup should have your house load connected to AC-out of the EasySolar.

Fronius can stay on the AC-in side if it is bigger than 3kW.

System should measure the SOC independently from BMS by means of SmartShunt or EasySolar's internal measurements.

BMS should never be used as part of the normally working system.

BMS tells the system to stop using battery when there is something wrong inside the battery. (high or low cell voltage or high or low temperature or overload)

-yes, on the AC out I have not connected anything for now, I will do it for critical loads but only after the system is stable and does not restart without reason interrupting the outputs.

- the system is self-consumption with storage. I store solar energy for use at night and for peak loads.

- ess system loaded and working.

The manual also shows the connection diagram as mine called grid parallel and in fact everything works very well apart from these problems.

The fronius is 3 kW.

For the BMS, what I have mounted is the seplos, very similar to that of the pylontech batteries and I do not know that other smart shunts or other things are needed to work with the victron ... my BMS has the shunt inside and communicates the soc al victron via can bus.

when the battery is 100% it stops charging and displays "# 3: BMS disabled charging"

this is my configuration but I had to put the Energy Meter after the fronius otherwise it would also count the watts put into the grid

@lucadea1985@gmail.com

What is your settings in "Grid feed-in" option in ESS settings?

Do you have "DC-coupled PV-feed in excess" selected?

AC pv on , DC pv off . I am not allowed to inject DC, only the excess AC. I would like to use DC pv for battery charging and for loads

@lucadea1985@gmail.com

Selecting AC-coupled PV ON, does not make any sense since you do not have AC-coupled PV inverter.

Selecting DC-coupled PV OFF is the reason why your PV is used only to charge your battery.

If you want to use your battery for loads you have to present a load for the battery to be used on.

Since you do not have any AC-out load the battery has nothing to supply load to.

If your setup looks like this.

it will not work properly.

Problems.

1. ESS does not work properly because it does not know what is happening at grid connection.

2. MPPT is charging only a battery and this energy does not have anywhere to go.

It shoul look like this.

1. ESS can control your "self consumption and storage" function of the system.

2. Your Fronius will work when grid is down.

3. Battery power can be properly used by ESS system for critical house loads.

4. External to the battery SOC measurement is needed if this system is not to be interrupted by BMS all the time when battery gets to 100%SOC.

sorry maybe I can't explain myself well.

my ess is working fine as you can see now both the PV DC and the battery are powering the loads but this only happens when there is a lot of load. When Energy Meter sees input on the grid, the load is taken by the fronius and the PV DC is reduced to the charge value set on the dvcc.

I cannot move the fronius, it must remain connected upstream

thanks for your help. The PV DC is not enabled to inject into the grid but manages the request on the load. as you see in the screenshot I sent earlier, the PV DC is powering the load aided by the battery because the Energy Meter has reached its reference limit of +50 watts it does not inject into the public grid. In Italy we have regulations and I cannot move the fronius, when the grill is missing the fronius must switch off.

My ess:

yet it seems not to have done anything strange. I followed the manual box. The production of fronius is detected via the LAN, and Victron fronius dialogue between them. The GX therefore has all the parameters or production fronius, PV DC output which is integrated into Victron et112 and with the flow from the counter calculating the watt from fronius. As a first test I put et112 upstream of the entire system but not charging an correctly when the fronius was active. Moved between fronius and instead load counts properly. For the fact of moving the fronius can not and will not do it because it is a system certificate in this way and there are electric company meter that monitors the production. In case of failure to the grid I, however, the PV DC operating.

I had installed like this scheme but the values were not detected correctly. The energy of the fronius was added to that detected by the et112... the only way to see the correct values was to move et112 after the fronius. The energy of the fronius is detected and used in the correct way, the problem is the reboots of the 100% battery system and the non-use of pv dc surpluses for loads when the fronius injects its surplus to the grid. an off grid system I can install but I can not touch or modify the existing and certified fronius. fronius must stay on ac in, everything else I can change it. what would you do? Thank you

Queste le mie impostazioni

ok I'll try. I update you. Thank you very much

I lowered the charging voltages so that the bms doesn't stop charging and the system doesn't restart anymore. Thanks for the tip.

There remains the problem of the ft dc which does not cover the load requirement when there is grid injection from the fronius

I was wrong, the Energy Meter is upstream. I moved the major loads to AC output out critical loads but as you can see in the screenshot the DC PV does not cover the loads, it is weakened when the battery is charged and the energy of the fronius is used. Instead, I would like the loads to be covered by the pv cc and the fronius completely injected into the grid. It is not possible to do it ?? thank you all

@lucadea1985@gmail.com

I am not sure but its logical to use Fronius energy first to power the loads because its DC-AC conversion is more efficient that MP-II's

Try not telling the system GX that you have Fronius connected at AC-in and install ET112 behind it. GX will use only DC-PV and battery and when its not enough it will pull energy from grid and when at that moment Fronius is producing it will be the source of the energy "from grid".

To be honest I would not worry abut DC-PV being throttled down.

now works. I had to set inverter / caricabatterie to grid meter setting in the ess menu.

but now I no longer have the critical loads output and I have no UPS function when the grid is missing.

Hello marekp, I had the wrong AC output ... the UPS function works correctly and now everything is connected on critical load but even so it doesn't do what I want. It is true that the energy from the fronius is more efficient but he also made a DC AC conversion, similar to what my easysolar would do ... the energy I would like to use for the loads would be free because otherwise my PV DC would be reduced to 0 watts. I think the problem is the fronius injection because the GX does not activate the PV DC until the 50 watt grid setup is exceeded, once this is exceeded, the PV DC also intervenes for the loads. Normally, however, he sees 1500/2000 watts of injection from the fronius and does not let me intervene the PV DC. If I disable the fronius al gx I lose the efficiency of the system as the battery is discharged even when I have a lot of surplus from the fronius ... I don't like it that way