Hi

I have two issues with my solar system that I could use some advice with.  I have 2x 5.5kw Sunsynk inverters with more than enough solar panels and battery storage.  From around 9am until 15:50, I run on solar with grid for backup (so that I don't need to check the sun while running the geysers and other heavy loads).  From 15:50 until the next morning, I run completely off-grid with a 20W grid trickle feed.  The system was installed in November when we finished building the house.  I very rarely use grid power:  Only when it has been raining non-stop or very cloud and even then, mostly to heat the geysers.

So my first issue is that if loadshedding hits, then I can see the light in my house slightly dim and fans running slower (even if I'm running off-grid), but more importantly, if my computer is running a slightly higher load than just idling (i.e. using the GPU), then my computer would actually restart during that dip.  I even bought a small 700W UPS but if I use the GPU, then obviously the PC is using more than that and restarts anyway.  This happens whether I'm running on-grid or off-grid and this is now becoming a frustrating issue.

The other problem is, although I'm managing it manually now, is that if I'm running a high load and loadshedding hits, then the whole system would shut down and restart.  The first time I was running about 7-8kw load (and I was generating more than enough from the sun), then when loadshedding started, the PV power suddenly dropped from 9kw to around zero, things started beeping and then everything shut down and rebooted.  The second time it happened, I was running around 4-5kw load with more than enough solar power and then all the previous things started happening about 10 minutes after loadshedding started.
I've mostly mitigated this for the 4pm loadshedding session by changing my timer to go off-grid from 15:50 instead of 16:00, so that solved the common 4pm slot, but now I still have issues if loadshedding starts at 12 or 2pm while I'm running heavy loads.

My power doesn't dip enough for PC's to go down but my APC 700 UPS does pick up the loadshedding dip for a brief moment; probably since the voltage then becomes a stable 230V instead of whatever Eskom feeds us normally. Nothing else in the house seems to pick up the power dips. 9kw seems like quite a load though, almost reaching the theoretical limit of 10-11kw provided by your combo. What batteries do you have? Maybe they can't provide enough power quickly enough for the inverter to not reset? The beeping and loss of power appears to point to that?

2 hours ago, ViperGTI said:

Hi

I have two issues with my solar system that I could use some advice with.  I have 2x 5.5kw Sunsynk inverters with more than enough solar panels and battery storage.  From around 9am until 15:50, I run on solar with grid for backup (so that I don't need to check the sun while running the geysers and other heavy loads).  From 15:50 until the next morning, I run completely off-grid with a 20W grid trickle feed.  The system was installed in November when we finished building the house.  I very rarely use grid power:  Only when it has been raining non-stop or very cloud and even then, mostly to heat the geysers.

So my first issue is that if loadshedding hits, then I can see the light in my house slightly dim and fans running slower (even if I'm running off-grid), but more importantly, if my computer is running a slightly higher load than just idling (i.e. using the GPU), then my computer would actually restart during that dip.  I even bought a small 700W UPS but if I use the GPU, then obviously the PC is using more than that and restarts anyway.  This happens whether I'm running on-grid or off-grid and this is now becoming a frustrating issue.

The other problem is, although I'm managing it manually now, is that if I'm running a high load and loadshedding hits, then the whole system would shut down and restart.  The first time I was running about 7-8kw load (and I was generating more than enough from the sun), then when loadshedding started, the PV power suddenly dropped from 9kw to around zero, things started beeping and then everything shut down and rebooted.  The second time it happened, I was running around 4-5kw load with more than enough solar power and then all the previous things started happening about 10 minutes after loadshedding started.
I've mostly mitigated this for the 4pm loadshedding session by changing my timer to go off-grid from 15:50 instead of 16:00, so that solved the common 4pm slot, but now I still have issues if loadshedding starts at 12 or 2pm while I'm running heavy loads.

What batteries are you using, make and capacity?

If you simulate a power cut does the same happen? 

If I have to venture a guess with the limited information, your issues are likely linked to a voltage issue on the AC side (supply and load). Perhaps a grid overvolatge just before the grid shuts down. I have seen that this can result In the inverter dialing back the PV at the time of the overvoltage and if the batteries cannot pick up the load then the system shuts down.

I'm using 5x Hubble 5.5kw Lithium AM-2 batteries.

 

4 hours ago, p_i said:

9kw seems like quite a load though, almost reaching the theoretical limit of 10-11kw provided by your combo. What batteries do you have? Maybe they can't provide enough power quickly enough for the inverter to not reset? The beeping and loss of power appears to point to that?

My load is about 7-8kw, the PV generation (which is sometimes around 1kw higher) is around 9kw.  Note that this (the high load with alarms during switchover) is my 2nd issue though.  My PC (1st issue) restarts regardless of the load, even if the total load is under 1.5kw.  With the UPS that I bought, the PC now only restarts if the PC is drawing more than 700W load.  That happens even if I'm already running off the batteries so technically there shouldn't be any switchover.

 

2 hours ago, I84RiS said:

If you simulate a power cut does the same happen? 

If I have to venture a guess with the limited information, your issues are likely linked to a voltage issue on the AC side (supply and load). Perhaps a grid overvolatge just before the grid shuts down. I have seen that this can result In the inverter dialing back the PV at the time of the overvoltage and if the batteries cannot pick up the load then the system shuts down.

I have actually not tried simulating a power cut.

What you say in your ventured guess sounds plausible.  Any idea how to overcome it?