I have Victron MultiPlus II GX with LiFePo4 batteries that I use as a backup/UPS for the grid failures.
Currently, there is no ESS assistant and batteries are 99-100% charged all the time.
So I came to the idea to use them partly during 07-23 time slot (with a 300 VA limit) and recharge at night when it is cheaper.
As I understood the only option is to install ESS assistant and to add a charging schedule.
My concern is that I don’t want to expose the voltage to the grid when there is a failure.
Is there a way to force feed-back relay open when grid fails?
With ESS, that is always the case – on loss of grid the relays open and prevent you from frying the poor linesman that out on the street that tries to get the grid back up…
You don’t need ESS to force the system to invert and supply from battery at specific times, there are other ways that can be achieved.
The inverter (dishcharge) limit is, however, a function of ESS.
ESS doesn’t feed back unless you want it to, and loss of mains detection in the MP2 prevents anything leaking during grid loss.
It is certified for this purpose, with dual relays, so, it can’t happen accidentally even if a relay welded itself shut.
I have searching for this kind of solution → You don’t need ESS to force the system to invert and supply from battery at specific times, there are other ways that can be achieved.
I have a “testinstall” with a MultiplusCompact 12V2kW and CCGX/700Ah LFP:s and I do have use for a scheduled use from battery and delayed charging, doing it manually now
Why;-) Living with Nordpool DayAheadPrice and peakshaving is the new usage of electricty to save costs when sun is on vacation here in Scandinavia
Today its about 18cnt/kWh+ transfer cost and tonight 0.8cnt/kWh
DESS is too complex and I am only buying, some feed to grid isnt a issue.(Grid is balancing the use) Feed to grid is OK whit a PV-inverter and panels on the roof + agreement