Solarmaxi

Thanks!!! 
This forum is great! A real brotherhood where we learn tons like you can end up actually charging yourself for the electricity you spent 100s of 000s to produce 🙈🤦‍♂️😭
 
Thanks to both of you @GreenFields @Kalahari Cruiserfor your helpful reply. I now have that little bit more insight into all this. 👏🙏🏼

Hi, I know this is an old thread, but just thought I'd add my 2 cents, hoping it will benefit others.
I'm kinda new to solar/inverters. Got my Deye inverter installed just under 3 weeks ago. 8kw inverter, and 4× hubble am5 batteries. Sounds like overkill, but figured I'd just bite the bullet, since it's best for the long run. Deep discharge cycles dramatically reduce the battery's life expectancy. If you can keep the battery between ~50% and 100% charge, it works wonders for longevity. 
Once you start draining your batteries deeply, it starts a vicious cycle, of needing to continuously deep-drain your batteries, as each deep discharge, will decrease capacity.
Just thought I'd put this out there.
What I really wanted to mention, is regarding those "grid charge" checkboxes, on the "work mode timer". 
Let's say your battery is at 81%, and there's no load shedding. When it drops to 80%, the grid will maintain the 80% charge. So long as there's no load shedding, throughout the night, given that you set the state of charge at 80% throughout the night, the inverter will use grid power to maintain that 80% charge.
But let's say there's load shedding from 20:00 to midnight, and let's assume that your battery was on 90% before load shedding commenced at 20:00. By the time it's midnight, and load shedding stops, your battery level might be around 65%. So when grid power is back, it will maintain that 65% charge. It won't recharge the battery back to 80%, because the "grid charge" checkbox, isn't ticked.
But if the grid charge checkbox was ticked, at the 00:00 to 04:00 time slot, then your battery would have been charged back to 80%, and the inverter would maintain that charge, until either another load shedding session, or your solar panels kick in, in which case, your battery will be charged back to 100%.
So it's all a balancing act. I'm still tweaking my timer settings, but I'm getting the hang of what works for my household. When winter sets in, and we start using heaters, that will be the real test, since the ladies don't wanna use gas heaters. But 800w bar heaters, used intermittently, should be manageable enough.
Here's how my timer is currently set:
01:00 to 05:00   65%  grid charge
05:00 to 09:00  55%  grid charge
09:00 to 13:00  60%
13:00 to 17:00   65%
17:00 to 21:00   70%  grid charge
21:00 to 01:00   65%  grid charge
 
It's set to basically never need to grid charge at all, but if for some reason, the battery percentages do drop below the limits I set, the grid will only need to charge them for a very short while, till we enter the next time slot, and the battery again begins to discharge.
Recently, we had a load shedding slot from 04:00 to 06:30, where the battery level dropped to 48%, hence I set the grid charge, for the 05:00 to 09:00 time slot. It's Ramadaan right now, so we wake up before sunrise, use the microwave, kettle, etc. So there's some significant battery drain in those early hours of the morning. 
Basically, I just need to grid charge to maintain a certain percentage, until sunrise, and the solar kicks in, then I'm generally back to 100% charge by midday, if the sun is shining. My inverter is set to prioritise the load, before charging the battery.
It's just around 23:50 as I'm typing this, and the battery level is at 75%. I'm hopeful that there will be no need to grid charge at all, throughout the night, but it's generally a close call, around 6AM. The battery might near the 55% mark around that time, but I'm hoping it will still be above 60%, in which case, I probably won't need to grid charge at all, until the solar kicks in, God willing.
Sorry for typing so much. For what it's worth, hope whatever I said is helpful. 

Yes a lot of q cells panels are fake too. 
What do we do if we find out that  we have received fake panels from suppliers (after money has been paid over)? Are we protected by the CPA? 

This will vary from inverter to inverter. Read the spec sheets for the inverters you are considering. Also check how many strings each inverter can take. I'd expect it to be two for most modern inverters, but play safe and check before you start putting all that hardware on your roof.
Usually the inverter will trip to prevent damage. My Goodwe immediately starts rebooting if there is grid or PV, but I am not sure that they all behave this way. 

Note that the batteries may also trip if they are overloaded. It's not necessarily the inverter. If your inverter can supply 5kWh, but your battery only 3, the battery will trip first. 

Voc is the open-circuit voltage, a specification of the solar panel. If you connect a string of panels to an inverter, make sure that the total Voc of that string is comfortably below the maximum Voltage that the inverter's inputs can handle.

On the Sunsynk, if the grid is available and the load is higher than the inverter rating, it will passthrough the balance above the inverter rating, therefor still supply what it can at that point.  If the grid is unavailable, it will trip