Hi,

I have a new 8kw Sunsynk inverter and have some questions about the way the system "Program Charge / Discharge Times Page" works.

I have read the manual and this thread, but am still a little confused.

Using the screenshot/setup from that thread:

 

Questions relating to a time during the night when there is no PV being generated.

1. What happens when the battery reaches the given SOC, does the inverter just stop supplying power?
2. Take row 1, does it mean between 01:00 and 05:00 the battery is allowed to deplete until 80% SOC and then the inverter stops supplying power?
3. If one had "Grid" ticked on row 1, once 80% SOC is reached, rather than cutting power would it switch to using grid power? Or does it mean that during this time, the inverter will use the grid to supply power unless the grid is not available in which case it will use battery until 80% SOC then turn off?

I'm most confused about question 3. I guess put another way, if Grid is checked, will the inverter use battery power until the battery reaches the given SOC and then switch to Grid, or will it use Grid as long as its available and if Grid is not available, will use the battery until the given SOC?

How are things different during the day when there is PV available? If you are pulling more than the PV can provide and Grid is not checked, I presume it will take the additional from the battery. If grid is checked, will it then take the additional from the Grid?

Thanks for 

Edited September 29, 20223 yr by Chris888

1. The inverter will not shutdown it will switch to taking all power from the grid as there is no PV at night. 

2.yes with no blocks ticked it is set to discharge and once 80% is reached it will switch to grid. 

3.Grid tick is for charging. So for example between 1am and 5am if the battery is above 80% it will use battery power until it drops to 80%.

However with grid ticked if the battery was ever below 80% at 1am it would use the grid to supply power and charge the battery back to 80%

Edited September 29, 20223 yr by Chris_S

PV is always prioritised, then battery(depending on settings) then grid

Edited September 29, 20223 yr by Chris_S

Another Chris 😀

Thanks, that makes more sense now.

This is the first day it has been running and the PV managed to supply what was needed during the day. The system first switched on last night so the batteries charged off the grid in the evening and were 100% the whole day today.

I have 15kw batteries 5KW PV.

I am thinking of just having it set to 40% SOC, no grid ticked, for all 24hours of the day and seeing how that goes. Does that sound alright?

 

Edited September 29, 20223 yr by Chris888

4 minutes ago, Chris888 said:

Another Chris 😀

Thanks, that makes more sense now.

This is the first day it has been running and the PV managed to supply what was needed during the day. The system first switched on last night so the batteries charged off the grid in the evening and were 100% the whole day today.

I have 15kw batteries 5KW PV.

I am thinking of just having it set to 40% SOC, no grid ticked, for all 24hours of the day and seeing how that goes. Does that sound alright?

 

Hi Chris😂

That's good. With a bit more PV you can almost go fully off grid. 

My only concern is loadshedding hitting at 40% SOC but that should be OK with 15kw of batteries(depending on your load requirements) but it's at night anyway. 

Just looked at your settings again. 

I'm sure if you have non-essential loads as well. You can check the export solar bat full box to push PV to non-essentials. 

17 minutes ago, Chris_S said:

Just looked at your settings again. 

I'm sure if you have non-essential loads as well. You can check the export solar bat full box to push PV to non-essentials. 

Hi,

 

The export solar does not need to be ticked to feed back to non essentials as long as grid is present. as long as limit to load is unticked it can feed back to non essentials, in my case, my geyser.

I only have one large aircon on non essential, but I guess that makes sense to use the PV for that if it is available.

How much more PV do you think would be required to go fully off grid? I guess matching the 8KW of the inverter?

When a meter/monitor was installed for a week, the max load that was used was 8.8kw and we averaged 16kwh a day. 

A bit off topic but I have the Sunsynk logger and app but am considering getting Solar Assistant as well. Have you got any experience with it, is it worth the money for the extra info? I do like data 😀

 

 

5 minutes ago, ZCS said:

Hi,

 

The export solar does not need to be ticked to feed back to non essentials as long as grid is present. as long as limit to load is unticked it can feed back to non essentials, in my case, my geyser.

Thanks for the clarification. 

I do have the CT coil installed and as mentioned there is only a large aircon that is not on the UPS side. So if the limit to load box is unticked, spare PV will be sent to the aircon as well, but if there is no grid, the aircon wont work? Do I have that correct?

 

5 minutes ago, Chris888 said:

I only have one large aircon on non essential, but I guess that makes sense to use the PV for that if it is available.

How much more PV do you think would be required to go fully off grid? I guess matching the 8KW of the inverter?

When a meter/monitor was installed for a week, the max load that was used was 8.8kw and we averaged 16kwh a day. 

A bit off topic but I have the Sunsynk logger and app but am considering getting Solar Assistant as well. Have you got any experience with it, is it worth the money for the extra info? I do like data 😀

 

 

Limiting factor is batteries when going off grid. If you had 3 days of heavy cloud you would be in trouble if you use 16kwh a day. You'll need to watch the data for a while and see where you can improve. 

1 minute ago, Chris888 said:

Thanks for the clarification. 

I do have the CT coil installed and as mentioned there is only a large aircon that is not on the UPS side. So if the limit to load box is unticked, spare PV will be sent to the aircon as well, but if there is no grid, the aircon wont work? Do I have that correct?

 

according to my (admittedly newfound) knowledge, yes, that is correct. 

@Chris_S and @ZCS thanks for the help.

Early days. Will keep an eye on the data and make the necessary tweaks. 

Will probably be back with more questions as well.

 

 

4 minutes ago, Chris888 said:

Thanks for the clarification. 

I do have the CT coil installed and as mentioned there is only a large aircon that is not on the UPS side. So if the limit to load box is unticked, spare PV will be sent to the aircon as well, but if there is no grid, the aircon wont work? Do I have that correct?

 

Yes with no grid only your load output will work so no aircon. Was your 8.8kw max load with the aircon running? 

1 minute ago, Chris888 said:

@Chris_S and @ZCS thanks for the help.

Early days. Will keep an eye on the data and make the necessary tweaks. 

Will probably be back with more questions as well.

 

 

Always a pleasure. I myself am quite new to all this but have learned a boat load just from this forum. always helpful forumites around to assist us

2 hours ago, Chris_S said:

Yes with no grid only your load output will work so no aircon. Was your 8.8kw max load with the aircon running? 

For contexts's sake - i am currently running 3 inverter aircons (2x9k btu and 1x18k btu) and the draw is only 2kw - running fine on a 5kw Sunsynk. They are all on the Essential (UPS) side

2 hours ago, ZCS said:

The export solar does not need to be ticked to feed back to non essentials as long as grid is present. as long as limit to load is unticked it can feed back to non essentials, in my case, my geyser.

Limit to load only is supposed to make use of the CT to prevent feedback to grid, at least that's how my Sunsynk was working... if you untick it, then it would feed to the grid as well, I believe...

2 hours ago, Chris888 said:

How much more PV do you think would be required to go fully off grid? I guess matching the 8KW of the inverter?

To go fully off grid, you'd have to cater for cloudy days, when not much power is generated by the solar panels... also it depends where you are located, Cape Town winters may not allow you to be off grid, in the Kalahari, yes, but our rainy seasons may require some extra solar panels to produce enough at times and too much most of the time... if your consumption is 16kWh/day, then you're probably covered with the panels you have, except, possibly on cloudy days...

3 hours ago, Kalahari Meerkat said:

Limit to load only is supposed to make use of the CT to prevent feedback to grid, at least that's how my Sunsynk was working... if you untick it, then it would feed to the grid as well, I believe...

If solar export is unticked then it shouldnt feed the grid. I have my geyser on the grid side with limit to load and solar export unticked.zero export ticked. As long as grid is present i can power my geyser from pv/battery. Once grid drops the non essentials immediately lose power.

17 hours ago, mzezman said:

For contexts's sake - i am currently running 3 inverter aircons (2x9k btu and 1x18k btu) and the draw is only 2kw - running fine on a 5kw Sunsynk. They are all on the Essential (UPS) side

Wow I wouldn't have thought that. Is that 2kw with all 3 running at once?

Just now, Chris_S said:

Wow I wouldn't have thought that. Is that 2kw with all 3 running at once?

yup - all 3 at the sametime.

4 minutes ago, mzezman said:

yup - all 3 at the sametime.

Impressive. Do you run them only when there is PV available or at night off battery as well? 

3 minutes ago, Chris_S said:

Impressive. Do you run them only when there is PV available or at night off battery as well? 

As its gotten warmer a lot more during the day (PV) then i use them to cool the bedrooms down off battery at night - i even had an automation that if the room temp got higher than X between 8pm and 5am then the aircon would turn on - will need to revisit it

7 minutes ago, mzezman said:

As its gotten warmer a lot more during the day (PV) then i use them to cool the bedrooms down off battery at night - i even had an automation that if the room temp got higher than X between 8pm and 5am then the aircon would turn on - will need to revisit it

This is going to make me re-think my install. Thank you. 

Hi all,

Newbie question but similar to what's been discussed

4.5kw solar setup

2. X greenrich 3.8kwh batteries

Sunsynk 5kw inverter 

As i understand it my installation has oven and geyser on non essential side. Remainder of house on essential.

During load shedding seems to be fine, charts show load pulling off pv and only batteries at night time shedding. Geyser and oven not supplied as non essential

When no load shedding however it seems the pv is keeping batteries charged at 100% and then throttling. But any load seems to be coming off the grid. Essentially PV or batteries don't supply load, either essential or non essential

I would like it to work as follows:

1.Load shedding essential only via pv and batteries - as is now

2. No load shedding - essential via pv and batteries and non essential ie geyser to be supplied by pv if sufficient available

 

Current battery settings

Zero export ticked

Solar export not ticked

Limit to load only not ticked

Priority load ticked

 

Concerned this may be due to a faulty installation

Any advice would be much appreciated.