I’m considering building an (D)ESS setup for at home. I’m in a discussion with a colleague who already has a setup. The question is, the AC In 1, is this connection only used for taking current from the grid to charge the batteries? Or is this AC In 1 connection also used to return current from the batteries into the grid/home electra network? Other way asked, is AC In 1 bi-directional used for loading and unloading the batteries and take/provide power to the grid/electra network?
Hello
Yes, it has bi directional capacity (also to feed loads that are behind the grid input and AC in of multiplus 2, subject to installation of a clamp or meter just after the grid input)
Excellent, thanks for the answer, this is very useful feedback.
So if you do not have any critical load, you don’t need the AC Output ports. By using the AC In port I can charget the battery from grid or my solar panels (with their own converter) and I can use the batteries again, through the same AC in interface, to feed the loads in my electra network.
This will simplify the installation. Only one connection from the electra network to the inverter. Perfect.
You can run it like this, but i advice you to use a meter on PV and a meter on the grid (ET112 and or EM540) that way the (D)ESS can calculate everything
Also do note that when you are not using AC out 1, there is no battery/pv backup when grid fails
Thanks @DuivertNL for your feedback. Indeed meters on the PV and Grid will be part of the setup. And indeed no power to the PV inverter means not solar PV, I’m aware of that indeed. I’ve seen a solution in which the Solar PV inverter is connected to AC out 1. Ultimately I want to switch my Goodwe inverter for Victron MPPT to directly load the batteries, this prevents two conversion steps and will be more efficient. Small steps at the time .
With regards to the bidirectional AC In interface, does this work differently on a Multiplus (compared to the Multiplus-II)?
Reason for asking, I’ve a Multiplus installed on the boat, when the inverter is on and I’m not connected to the wall power, I don’t have power on the outlets on the boar. Only on the AC Out.
Not really, when grid is not connected on the multiplus 2 ac in is also disconnected
Big difference i think is that the multiplus 2 conforms to more grid regulations/anti islanding
Clear, thanks @DuivertNL. You need Voltage in the AC In to be able to deliver current to the grid. Understood.
More follow-up questions linked to this. In many setups you see the DC-AC PV inverter connected on the AC Out 1, the reason for this is that when there is no Grid voltage/connection, the PV keeps working and batteries are being charged. This means that the AC Out 1 is also bi-directional, and the batteries can be charged through the AC Out 1 as well, correct?
Yes you can connect an PV inverter on AC out 1, but follow the victron 1:0 rule (pv inverter power may not exceed multiplus inverter power)
Thanks again @DuivertNL this is clear as well, I need to buy an inverter with enough power capacity also for the future in case I want to extend the PV. Ultimately I want to swap the PV inverter to a Victron MPPT to reduces the losses of the existing PV inverter.
Based on your feedback above, the AC Out is also bi-directional? And the batteries are charged through the AC Out interface as well.
Yes it is, all documentation on these topics is available on the victron site