So it should be easy to spot your house in Bridgewater. It’s the one with the big-*ss solar array 
Goeie Genade. That is quite good. What is your panels angle and direction?
Aaah you guys are right. Indeed 6mm it is. I keep samples of the cabling around the house to take with when going out to purchase lugs etc. Guess I grabbed the wrong sample.
Keep it to <60A, but then you still have lots of capacity on those cables
I sit with a 5Kw array, but my inverter limits me to 2,4 - 2,9Kw
I need a 5Kva unit. I suppose my MPPT’s would need upgrading as well?
Definitely, what you can produce should be the driver, and in the absence of better data theoretical values is the best data you have to work with.
However, that is no longer your situation.
Your panels are up on the roof now:
1.) At their final tilt and direction,
2.) At their typical working temperatures
3.) As typically dusty as they are likely to get
4.) With genuine cable and MPPT/inverter losses.
Now that you have historical data don’t ignore it. This now becomes your best available data set.
You may still turn out to be quite correct in your assumption, but why assume?
When I have conducted this exercise before now, I found big differences between theoretical values and real-world values.
Definitely, I haven’t been doing this long and I already see this too
The option I have explored is the Fronius AC inverter - you can add it anywhere you have an AC connection and don’t need your panels to be close to the batteries at all. I have a great roof 70m2 but its 200m away so for battery charging during the day the Fronius is a good solution. Not cheap but …
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As in, anywhere there is AC in the house? Meaning I could even connect it directly to a wall socket?
I know nothing about the Fronius and must still read up on it but if memory serves, the Fronius produces AC directly from what the panels gives it?
Maybe not from the wall socket 
but it can be connected to a SubDB somewhere (with protection obviously) … As long as you have the cable rating for the AC input you will be fine. It produces AC from the panels and will talk to the GX to tell the Multiplus to charge batteries.
See this page!
Fascinating. Sorry for all the questions, I will still read up on it.
So you’re saying it will not interfere with the working of the Multiplus? But seemingly it does still need to be connected to the Gx device via a cable of sorts?
Its worth reading the installation manual. It doesn’t need to be connected to the GX (if you don’t want it monitored). It “talks” to the Multiplus and is controlled using frequency shifting. I do believe you need a GX device though. I don’t have one installed but have been exploring options for me here on the farm. Roof space near my batteries is very limited!
I suppose just as the Multiplus knows when extra power is needed in the house through the input of the ET112 presumably, it will pick up on this when there is an alternative source of AC input in the house?
Here you go… Nice clear explanation!
60A may be OK for the cables, but way too high for the MC4 connectors. I am not sure if they come in 20A and 30A ratings. I have always bought MC4’s that are supposed to be 30A, but I don’t know if that is a Chinese rating. I do rate my strings for 30Aish and I haven’t had a problem. (So far).
Obviously, other connectors can be used, but I find the integrity of MC4’s to be very good, not to mention the convenience factor (and panels come equipped with them).
No 
Technically yes, it would work. But it would never pass…
It should ideally have its own connection to a DB or Sub-DB with its own breaker (to protect the cable) and of course any other cabling needs to be rated for how much power it will put out. It should not just be be connected to the nearest “plug circuit”.
A scenario I get often is that someone wants to put PV modules on an outbuilding, but the outbuilding is quite far away from the battery bank, making DC-coupling infeasible. But… quite often the outbuilding has an AC connection with a Sub-DB of its own… making a PV-inverter an excellent option for tying in that additional PV.
Yes and no. In an off-grid situation, it can adjust power using frequency shifting. When coupled to the grid, it cannot (because you cannot shift the frequency of the grid). Then it does need to be connected to the GX device, but it doesn’t need dedicated wiring for this. It simply needs to be connected to the network using either an ethernet cable or Wi-Fi. The GX communicates with the PV-inverter using Modbus-TCP (TCP as in TCP/IP). Supported PV-inverters can then limit power and avoid feed-in even while connected to the grid.
Correct. It can see power flowing into the grid using the grid meter, and just like it will attempt to keep the grid meter reading low by taking power from the batteries, it will also attempt to keep the reading low (in the reverse sense) by charging the batteries with any power that a PV-inverter is making. It keeps the grid meter at zero (or whatever you set it to) in both directions.
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Thanks @plonkster
Thanks guys, I need to look further into this.
I already have a sub db in the garage where my entire setup is (Multi is connected to it) with enough space for extra breakers etc so this could work.
But I will be left with only wifi to connect the Fronius to the Gx as my Venus is so full of cables already, I don’t think there is space left for any form of ethernet cable
Now THIS I like!!! Hel maar die goete is slim uitgedink!
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