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Hi all
Just trying to get my head around how anti-islanding works on the Multiplus 2 when you have grid tied PV.
How does the inverter know the grid is down if the PV is still supplying 230v if the ESS system is keeping the solar inverter active?.
For it to work, do I need to get the solar AC feed moved to one of the input / outputs on the bottom of the inverter so the system knows grid power failed?
Thanks
Simon
If the PV inverter is grid tied, it will turn off when grid fails.
The only way to have the PV inverter keep producing after grid fails, it has to be connected to AC-out of MP-II (keeping 1:1 rule in mind).
The solar power feed comes from the solar inverter, though a meter and is then wired into a MCB inside the main consumer unit
I therefore assume that the Victron unit can tell the difference between solar coming onto the house wiring over grid power somehow, this is what was confusing me as to know how to shut off AC on the AC in connectors and therefore forcing the solar to also shut down
I was planning to install the inverter onto a MCB in the CU (32amp) wired with 4 or 6mm cable to the AC in, only want ESS so wasn't going to use the 2 AC outs in anyway and wanted to check i didn't need to install anything else for anti islanding to work
Thanks again
Can you include some kind of diagram of what you intend to do?
As I pointed out before, if PV inverter is located between grid and AC-in of MP-II, it will turn of automatically when grid fails.
The loads will be supplied by MP-II from battery but you will not get anything from PV inverter even if Sun is shining.
If that PV inverter is made by Fronius it can be connected to the GX device and GX will know how much Fronius is producing. In ESS setup it is a good idea to install a grid meter at the grid point (between a grid and PV inverter) and set it up in the GX device.
If your PV inverter cannot be connected to GX device you will have to buy compatible power meter for measuring this inverter production and that power meter will tell GX device how much energy PV inverter is producing.
Hi Mark
Thanks again for your reply, is the attached enough info?
Plan installing a ET112 in the incoming grid supply.
Solar inverter cannot be connected to the GX
All loads running off the CU
Just want to make sure i wontt have any feedback to grid in event of failure
I am not sure if Solis inverter is able to be connected directly to Cerbo. Probably not. Therefore you will need to install another ET112 at its output to tell Cerbo how much energy Solis inverter produces.
I assume that this "FIT Meter" was installed by grid authority so the additional ET112 needs to be installed in line with it (between FIT meter and CU)
When grid fails, Solis will turn off and the input relays at MP-II's AC-in will open making the MP-II separated from the grid.
You will have to make sure that the MP-II's antyislanding system is certified in your country.
If not you will have to install external one.
Correct, the Solis inverter cannot connect to the GX. The fit meter was installed by the installers and measures generation for the purpose of my feed in tariff.
So, 2 ET112's it is then, one on the incoming live phase from the grid and one on the live feed between the FIT meter and my consumer unit
Will do re the certification
Thanks for all your help
Simon
