Sunsynk 8k - Micro Inverter Input Test

26 March
Wanted to test the functioning of a Grid Tied inverter as input on the Aux port of my 8k Sunsynk with battery storage.

Ran a temporary cable from my 2nd, Grid tied, 8kW Sunsynk into my Aux port and simulated a grid outage to run the batteries down to the 96% start up setting.

It worked as described - the only problem being how the input power is displayed.

On the flow diagram the Aux input shows only 2w when the input was actually around 800w.

That is not the strangest.

When I stopped the test by changing the setting back from Micro Inverter to generator, the Aux and the UPS displayed 32,700w and 33,300w respectively.

It stayed that way until I restored grid input and then normalized.

Any idea of what it can be ? March
Wanted to test the functioning of a Grid Tied inverter as input on the Aux port of my 8k Sunsynk with battery storage.

Ran a temporary cable from my 2nd, Grid tied, 8kW Sunsynk into my Aux port and simulated a grid outage to run the batteries down to the 96% start up setting.

It worked as described - the only problem being how the input power is displayed or rather not displayed.

On the flow diagram the Aux input shows only 2w when the input was actually around 800w.

That is not the strangest.

When I stopped the test by changing the setting back from Micro Inverter to generator, the Aux and the UPS displayed 32,700w and 33,300w respectively (Yes 32,7kW)

It stayed that way until I restored grid input and then normalized.

Any ideas of why that happened ?

27 March
Was cloudy yesterday so decided to run the test again today with the higher PV input on the Grid Tie and to test what happens when the batteries near 100 %.

The battery inverter does infact shift the frequency on its Aux output to tail off the Grid Tie - See image showing 52Hz on the Grid Tie’s “Grid” Input. -

It doesn’t seem to be proportional / linear - It just raises the frequency to the Setting in Aux screen and the Grid Tie stops producing.

At that moment the Hybrid starts using battery to run the loads - for maybe 30 seconds - and then the cycle starts again.

Overall it works as intended, except for the display of the flow of power.

Without monitoring the Grid Tie separately, there is no logical way of visualising how the power is distributed.


This is just before the frequency shift

This is with the frequency shifted to 52Hz