This is my plan, I just cannot seem to get it right. 
My client has two separate Solar systems on his property, with no Eskom at all. One Deye 16Kw with 34 x 550w panels powering a little shop. Peak load is around 11Kw. There is no more roof space or ground space for panels here. 

About 50m away is his dwelling powered by an 8Kw Deye with 24 x 460W panels. Peak load is around 4Kw There is an existing unused 10mm AC line running underground between the two buildings, I decided to use this cable. 

My plan (if possible) was to send excess solar power from the 8Kw in his dwelling to the 16Kw in his shop when it is cloudy. I connected the linking AC line to the “Gen port” of both inverters. As for programming, I set the 8Kw’s Gen port as “smart load” so that anything over 2Kw in solar power (and 95% battery SOC) should send 2000w of power to the 16Kw. So I assumed. On the 16Kw side I firstly tried the Gen port as a microinverter input. Section 5.9 of the Deye manual says this will work with microinverters and  “grid-tied” inverters. 

On my testing the 16Kw pulled 8.3Kw from the 8Kw and it tripped. I then tried to set the Gen port as a generator input and still it pulls 8.3Kw from the 8Kw system. 
I then tried to feed the incoming AC line into the Grid port of the 16Kw and turn on the grid peak shaving at 2000w. Still the 16Kw pulls 8.3Kw from the 8Kw and it trips. 

What am I doing wrong? 
Has anyone ever done anything like this? 

You can connect it via the Gen port & then input a Gen size kW limit on the same page. See below. You need to size the Gen size otherwise the 16kW machine wants to drink maximum power which is beyond the 8kW rated machine. 

9 minutes ago, Steve87 said:

 

You can connect it via the Gen port & then input a Gen size kW limit on the same page. See below. You need to size the Gen size otherwise the 16kW machine wants to drink maximum power which is beyond the 8kW rated machine. 

 

I tried this too, I set it to 2000w in the generator input window, but still it pulled 8.3Kw and tripped the 8Kw inverter. 
I also tried another option where under advanced settings where there is a tick box called “Gen peak-shaving”. I ticked this and 
the same thing happens, it pulls what appears to be maximum power from the 8Kw. 
 

Thanks for your reply. 

57 minutes ago, Steve87 said:

You can connect it via the Gen port & then input a Gen size kW limit on the same page

I also tried to go to the battery setting page 2, ticked "gen charge" and set the current to 10A. Still, it pulled over 8Kw from the other side and tripped the inverter. 

1 hour ago, Gandalf said:

My plan (if possible) was to send excess solar power from the 8Kw in his dwelling to the 16Kw in his shop when it is cloudy. I connected the linking AC line to the “Gen port” of both inverters.

Just my 2c. This doesn't make sense. Forget for a moment that the 8kW is a hybrid inverter with a Gen port and battery. In a normal AC-coupling scheme your micro-inverter does not have a Gen port. When the inverter is operating as a micro-inverter does in grid-tied mode (without a battery), the connection is to the Grid port on your 8kW inverter. The Gen-port on the 16kW inverter should then be acting as the controller that sets up the micro-grid by using frequency-shifting to control the output from the micro-inverter.

13 minutes ago, GreenFields said:

Just my 2c. This doesn't make sense.

I thank you for your reply, I welcome all advice and/or criticism equally. If my idea is totally stupid, I will accept that and make another plan. 

I totally agree with everything you say. In this case I am trying to use the 8Kw as a grid-tied/micro-inverter and then feed excess solar power via the smart load feature. With all the settings on the 16Kw I would imagine that it only pulls the programmed amount of power, but it doesn't. Sadly, I don't find any way to limit the feed from the 8Kw side either.

Tell me this cannot be done, and I will accept my fate. 

The capacity on most units for AC coupling closely matches the output capacity of the inverter due to the unit needing the ability to take on the full power of the system it is coupled to for short durations without damage or shutting down. So an 8kW inverter should be able to AC couple roughly 8kW AC of PV (typically close to 9.5kW DC).Like @Steve87said the 16kw inverter will demand way to much from the 8kw inverter.

30 minutes ago, TaliaB said:

The capacity on most units for AC coupling closely matches the output capacity of the inverter due to the unit needing the ability to take on the full power of the system it is coupled to for short durations without damage or shutting down. So an 8kW inverter should be able to AC couple roughly 8kW AC of PV (typically close to 9.5kW DC).Like @Steve87said the 16kw inverter will demand way to much from the 8kw inverter.

Thank you for the clarification @TaliaB.

I have accepted the fact that I have to run PV cables to the other side of the property. I will likely use 8mm or 10mm cable to compensate for losses. 

Hi

I am not a sparky so cannot offer advice of a technical  nature, to get away from the complexity of trying to get it work as you have tried, would it not be easier

to use your supply from the 8kw inv to a change over switch in the w/shop so that when solar power is low you can bypass certain equipment in the work shop to draw

from the 8kw system instead of the 16kw system?

Just a thought, may work may not.

Good luck

Hi @vrystaat
I understand what you are saying and I have to admit it sounds a lot easier than what I was trying to achieve. 
 

I was trying to go too elaborate and make things automated when someone there can just flick a switch. It’s so simple. 
 

I think I will go with your plan instead. 👍

Hi

Glad my idea can help you.

Let us know how it works out.

Cheers

Sean

On 2024/05/20 at 10:25 PM, vrystaat said:

Hi

I am not a sparky so cannot offer advice of a technical  nature, to get away from the complexity of trying to get it work as you have tried, would it not be easier

to use your supply from the 8kw inv to a change over switch in the w/shop so that when solar power is low you can bypass certain equipment in the work shop to draw

from the 8kw system instead of the 16kw system?

Just a thought, may work may not.

Good luck

An AC Changeover where the "priority" loads have 2 alternate feed-ins does sound easier indeed