I have a Sunsynk 8kw inverter with 3 x Pylontech UP5000 and 5.5kw of panels.    By DB has been wired for essentials (lights plugs) and non-essentials (pool pump, geysers).    If I set up Aux Output (which is wired to the "non-essentials" on the DB) it all works fine, until the grid goes down.   At this point the inverter gives an F18 error and we wait about a minute for the power to come back on ... it runs for a minute or so and then goes through the same cycle.     If I then remove the Aux Output (smart load) setting the inverter resets itself and is all fine and runs flawlessly.

I mailed Sunsynk and they sent back the rather cryptic "Please adjust grid low disconnect higher and output volts higher."    Current settings as per image.    I would really like to use the aux output rather then pumping back into the grid.   Was wondering if anyone else had had a similar issue and managed to resolve it?

This may help:

 

I'm not exactly sure what you mean by saying that the AUX port is wired to the non-essentials. Are you using a change-over switch to transfer your non-essentials loads to the AUX port, because that makes sense? Or are you trying to activate your non-essential load by transferring the AUX straight onto the non-essential circuits when the grid goes down, because I can't see that that would work?

Or could it simply be that your loads exceed the 8kW that the inverter can supply without the passthrough of power from the grid? A couple of geysers, a pool pump and the rest of the house could get you there in no time.

8 hours ago, Kalahari Cruiser said:

This may help:

 

Thanks Kalahari Cruiser, interesting reading, thanks!  I have changed the grid settings as per this thread from dropping at 185v to dropping at 210v - let's see what happens.

21 hours ago, GreenFields said:

I'm not exactly sure what you mean by saying that the AUX port is wired to the non-essentials. Are you using a change-over switch to transfer your non-essentials loads to the AUX port, because that makes sense? Or are you trying to activate your non-essential load by transferring the AUX straight onto the non-essential circuits when the grid goes down, because I can't see that that would work?

Or could it simply be that your loads exceed the 8kW that the inverter can supply without the passthrough of power from the grid? A couple of geysers, a pool pump and the rest of the house could get you there in no time.

Apologies, my terminology is incorrect.... Aux Port is wired to smart load (I hope that makes sense?)    It works 100% during the day, within it's battery parameters, and the load is never more than 3000w while my essentials never draw more than 1000w.    I should note that the Aux Load setting has "grid always on".   

 

I did increase the grid disconnect from the preset 185v to 210v (as recommended in the referenced post above) and waited for loadshedding.   

 

This time the inverter switched off output to both essentials and aux (as it was above the preset battery parameter) and then came back on 60 seconds later with load to essentials, but not smart load.    In the past it has reset like this several times, this time it only did it once.

I will email Sunsynk support again with this update and see if they have any other pearls of wisdom.