Jeff-dandare100

Here is what I ended up doing : It is working very well, thank you for the idea. Roll on summer

Thank you for the insight and links guys.

Hello guys. I have what probably seems like a doff question. Should the extra 4 fans of this mod on the side be switched on and left on (resulting in the inverter running very cool) or be controlled by the internal temperature and turned on when needed ? The reason I ask is : Does the constant cooling and heating affect the inverter at all ? ie Does the temp change of around 15 degrees up and down (many times a day) cause the components in the inverter, on the heatsink with thermal paste, to degrade, crack or move ? Or am I living in the dark ages and worrying about nothing ? Shot Jeff

Very cool, thank you. The behaviour identical. I am a lot more comfortable that it is not a site issue now. Thanks again, I appreciate the effort.

Still the same behaviour at 80%. Your explanation regarding the mppt's makes sense, there is nothing else but battery to fill that gap when switching loads. I would expect it to be a lot smoother with a constant load though. It's almost as if the gain in the system is to high during the 100/97 % or the PV is fighting the discharge attempt/s. (And only when no grid) I guess I am not alone with this so I will live with it and see if any future firmware upgraded on the inverter or BMS improve it. Thanks for the insights

Thanks @Chris_S. I appreciate the reply. I will set it to 80% and check what impact it has.

*bump, apologies Can anyone confirm the need to have grid available to keep the stability between the PV trying to charge the batteries when there is plenty solar and the batteries filling in the PV "ramp up" time in the absence of grid ? This is doing my nut but happy to leave it if anyone else experiences the same.

My SunSynk batteries do exactly the same . It charges to 100% then go down to 97/98% (after about 2 hours) and stays there. During this period of 100 -> 97, if grid drops and there is PV I have picked up strange behaviour that I am trying to verify Details here :

Hello I have noticed this behaviour below and would like to see if anyone else experiences the same. Sunsynk 8kW Hybrid Inverter 2 x Sunsynk 5.32 Batteries 16 x JA 545W Solar Panels Everything works fine and is in balance on a normal day with sun and grid available. The batteries charge up in the morning, and once charged, the power graph for the batteries is nice and flat while the PV supplies the load. Once the batteries reach 100%, they gradually go down to 98% or 97% and stay there while there is PV. The system table during the daytime slots is set to 100% and grid/gen are unticked. Priority load is also ticked and I am not exporting. However, if during this period of discharge from 100% to 98/97%, grid is lost (load shedding), the batteries start to chatter between discharge/charge/discharge/charge until the 98/97% is reached. This takes place for about 60-90 mins. It is almost as if the PV is fighting to charge the batteries and the batteries are fighting to discharge to the 97/98% level. If grid returns during this time, balance is restored and the battery power graph levels out again. Some things I have noticed : The sunsynk.net site graphs have a low sample rate so this behaviour is not easily visible on those graphs. I monitor the battery power value from the inverter itself (through a sunsynk plugin running on HA) and because this is realtime, this behaviour is easier to spot. I can actually see on the batteries themselves (the LED lights on the front) that they switch between discharge/charge/discharge/charge every 7 seconds or so. I can hear a relay clicking in the master battery. NB : This only happens while the batteries are between 100% and 97/98%. Then it's almost as if when the "balance" is reached, the inverter no longer tries to charge the batteries. (correctly so) Here is a graph to illustrate what I mean : The green circle is the battery power once charged, grid present and plenty PV. The red circle is when the grid drops (load shedding). You can also the minute/small attempts to charge in the red circle. This image below illustrates the same thing but includes the SOC. You can see that once the SOC drops to 97/98% the "chattering" stops Does anyone else have the same behaviour ? Does anyone else's battery discharge from 100% to 97/98% (and stay there) during the day or after a full charge ? Any opinions or insight is appreciated.