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Sunsynk inverter optimum settings?

LordQuas

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Jul 15, 2022
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I have a SUNSYNK 3.6KW HYBRID INVERTER and 5.12 kWh SUNSYNKL CATL BATTERY with 3.6 kWp of solar PV recently installed on my house in the UK.

My question is on optimising the settings of the inverter to do just one thing:- minimise draw of power from the grid.

With the good summer days in the UK at the moment the battery is charging to 100% but about 10 am (starting from sunrise at about 5.30 - 6 am) and from then on exports to the grid. While charging in the morning it will still be drawing a small amount of power from the grid (50-60 kW) when it seems like it could afford to export that small amount rather than import while still comfortablly getting to 100% charge over the day and handling the load from what the PV is making. So is there some way to avoid that import while battery is < 100% when still early in the day?

Second, when the sun has gone for the evening it will run off battery power plus grid through the night. I guess the ideal would be to draw as much battery power over grid until it hits 20% (seems like it is not stable to allow the battery to go below 20% SOC?) before the sun comes up and takes over the load (i.e. it is not efficient to be drawing grid during the night if battery is still above 20% SOC). Is there a setting in the inverter to tell it to make sure it discharges the battery (to 20% SOC?) before taking any grid?

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Lastly, this is all normal load type conditions so far. During peak load, such as cooking or kettles, how do I make sure the load is taken from battery (or battery + PV) and not any grid - particularly during the day when the battery will get a chance to recharge again? I tried using the Peak Shaving tick box which allows a minimum value of 1000 W and it would certainly work to take no more than 1 kW from the grid during peaks but it worked to take the FIRST 1 kW from the grid and then the balance from battery (i.e. if the load was 1.5 kW it would take 1 kW grid and only 0.5 kW battery, which doesnt seem optimium when the battery could probably do the whole 1.5 kW).

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I attach photos of my setup screens. Happy to share more if it helps.

Tom
 
Your system mode settings are weird ...

1. If you set every time stamps at 20%, your batteries will remain at 20% at all time except when sun allows excess power to charge the batteries. But when there is no sun, your batteries will stay at 20% and you will only use the grid ...

2. Your schedule should start at 1am & finish at 1am or whatever you choose but don't repeat the same schedule with different values or your inverter will not understand what you expect. It's fine at present because your SOC value is the same at all time but as in 1. It shouldn't.

So, it will require some tweaking depending of your actual load & solar power generated but more productive settings would be, for example :
1 - 8 : 20%
8 - 12 : 80%
12 - 14 : 40%
14 - 16 : 80%
16 - 18 : 60%
18 - 1 : 40%

This way your batteries are discharged during the zero sun hours (16 to 8), then charged to 80% then 40% then 80% again during the sun hours (8 to 16). Those numbers will need to be adjusted but there is no way to tell except studying your daily usage & solar power generated.

Grid peak shaving will limit the power taken from the grid to 1000w at all time unless alternate sources of power (solar + battery) can not supply the load. Then peak shaving is ignored. If you want less than 1000w taken from the grid, you need to change your time of use settings / add more panels / add more batteries / reduce the load. It depends ;)

Inverter is consuming +/- 50w, taken from the grid as long as grid is present.
 
Goodness I'm finding this all so confusing.
So I have the same set up. Sunsynk hybrid inverter and 5.2kw battery.
I have 10 panels.

I have Octopus Go so I have 4 hours of super cheap electricity each night.

I have the inverter set to charge to 80% through these cheap hours but not really sure how I should set the other 5 time slots.
So far I've been trying to set things up on the app rather than go up into the loft all the time.
Any help or advice would be so appreciated
 
Goodness I'm finding this all so confusing.
So I have the same set up. Sunsynk hybrid inverter and 5.2kw battery.
I have 10 panels.

I have Octopus Go so I have 4 hours of super cheap electricity each night.

I have the inverter set to charge to 80% through these cheap hours but not really sure how I should set the other 5 time slots.
So far I've been trying to set things up on the app rather than go up into the loft all the time.
Any help or advice would be so appreciated
Have exactly the same setup but haven’t figured out yet how to charge battery from cheap rate!

How did you set yours up?
 
It very much depends on how much you can access in the app. I managed to sort it by going to equipment, then settings, and then system mode. In there you'll find a toggle that says 'use timer'. If you switch that over it gives you 6 timers. Grid charge, and gen charge.
I selected grid charge time one. When selected it turns orange. Then lower down you can set when you want that timer activated.
Now, here is a disclaimer. I'm telling you this from memory as my system has a problem (my panels are barely collecting energy even in full sun) so the installer is looking into it. In doing so they removed my rights to tweak settings.

I would suggest you speak to your installer and ask them to set it up for you... Should have stared with that rather than whittering on!!
Anyway. Hope any of this is useful
 
@StephenN and @LordQuas - did you manage to get your systems set optimally? If so, would you be kind enough to share?
I too would like to see if you managed to set your system optimally @StephenN & @LordQuas and whether the suggestion below is optimally suited to summer rather than all year round and if tweaking 16 - 18 and 18 - 1 both to 20% for winter works better? @Zivva any thoughts?

1 - 8 : 20%
8 - 12 : 80%
12 - 14 : 40%
14 - 16 : 80%
16 - 18 : 60%
18 - 1 : 40%
 
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I too would like to see if you managed to set your system optimally @StephenN & @LordQuas and whether the suggestion below is optimally suited to summer rather than all year round and if tweaking 16 - 18 and 18 - 1 both to 20% for winter works better?

1 - 8 : 20%
8 - 12 : 80%
12 - 14 : 40%
14 - 16 : 80%
16 - 18 : 60%
18 - 1 : 40%
I had to get the solar guys back to tweak things and they also fitted each panel with optimisers. It's made a world of difference and on a cloudy day it pulls around 150 to 200w. When sunny I've seen it pull 800w but near in mind it's only been working properly for a week or so, so what it will pull in summer isn't known yet.
The battery is set to charge to 100% during my cheap hours at night (between 00.30 and 04.30). The rest of the time the minimum is set to 20%. In summer I hope to disable that.
I'm not sure why you're setting the various percentages.
Can you enlighten?
I'm really new to this.
 
I had to get the solar guys back to tweak things and they also fitted each panel with optimisers. It's made a world of difference and on a cloudy day it pulls around 150 to 200w. When sunny I've seen it pull 800w but near in mind it's only been working properly for a week or so, so what it will pull in summer isn't known yet.
The battery is set to charge to 100% during my cheap hours at night (between 00.30 and 04.30). The rest of the time the minimum is set to 20%. In summer I hope to disable that.
I'm not sure why you're setting the various percentages.
Can you enlighten?
I'm really new to this.
@StephenN I too am new to this as only had the panels and battery in since late October 2022. A friend shared this thread with me and I'd followed the suggestion of @Zivva . I just thought you'd also tried his suggestions.
 
@StephenN I too am new to this as only had the panels and battery in since late October 2022. A friend shared this thread with me and I'd followed the suggestion of @Zivva . I just thought you'd also tried his suggestions.
Not tried those. I'm not sure what they are supposed to achieve but will await and see if it becomes clear through further comments :)
 
These are the settings I've applied this week & also a prepared minor adjustment for Spring/Summer. I'm UK based.

AUTUMN & WINTER

Time slotBattery LevelGrid charge
01:0020%YES
08:0080%NO
12:0040%YES
14:0080%YES
16:0060%NO
19:0025%YES

SPRING & SUMMER

Time slotBattery LevelGrid charge
01:0020%YES
08:0080%NO
12:0040%YES
14:0080%YES
16:0060%NO
19:0040%YES
 
Not tried those. I'm not sure what they are supposed to achieve but will await and see if it becomes clear through further comments :)
@StephenN - my understanding is the percentages are the minimum level the battery will discharge to when feeding the house load. But happy to be corrected by anyone if I am wrong :)
 
@StephenN - my understanding is the percentages are the minimum level the battery will discharge to when feeding the house load. But happy to be corrected by anyone if I am wrong :)
Yes I believe that to be true, but I don't understand why they vary.
Mine will charge from grid to 100% between 12.30 and 4.30 am and a minimum level of 20%
 
Page 48 of the inverter manual would suggest this is correct. By seting charge from grid during a time window, it will charge to the amount you have set. By just having the % SOC it will simply not go below this, so it will use whatever system, be it solar or grid to bring it back to above that level.

However, I am having an issue with my battery where it doesn't seem to want to charge more than 270W per hour. I speculate that this might be because it is in the Garage and in the UK at the moment it is -5 degree but I can't be sure, has anyone else seen a similar issue before?
 
Page 48 of the inverter manual would suggest this is correct. By seting charge from grid during a time window, it will charge to the amount you have set. By just having the % SOC it will simply not go below this, so it will use whatever system, be it solar or grid to bring it back to above that level.

However, I am having an issue with my battery where it doesn't seem to want to charge more than 270W per hour. I speculate that this might be because it is in the Garage and in the UK at the moment it is -5 degree but I can't be sure, has anyone else seen a similar issue before?
What level of solar production are you achieving? Is the inverter set to Priority Load or Priority Battery? Have you set it to Grid Charge (don't, unless you get off-peak rates!)? It may well be that if it's set to prioritise your domestic load, there's little or no spare to charge the battery. That's certainly what I'm experiencing in northern England at the moment.
 
What level of solar production are you achieving? Is the inverter set to Priority Load or Priority Battery? Have you set it to Grid Charge (don't, unless you get off-peak rates!)? It may well be that if it's set to prioritise your domestic load, there's little or no spare to charge the battery. That's certainly what I'm experiencing in northern England at the moment.
I'm moving to eco7 in the next few weeks so I am trialing using grid to charge at night. Go back a week and the battery was charging off the panels (was managing 2kw during the day) of which 1.5kw was going to the battery. However today, only 0.3 from a similar level of generation was going to the battery, the rest was going to the Grid. It was almost like the battery couldn't take the extra charge or something? The same happened over night when I tried to use Grid charge, it only chaged it at 0.3Kw, so only achieved 35% SOC in 4 hours. No setting have changed from last week so I can only assume it was the cold causing this slow charge, but I wondered if anyone had any experience of this?
 
I have a Sol Ark and extensively use TOU rates to my advantage. I have attached my settings. I leave grid charge checked in all time slots and 40% state of charge. Our next day rates are published at 17:30 each day so I find the cheapest 2 hrs of rates and then I program those times into a slot and change the state of charge to 100% for that time period. At that time period my Sol Ark goes on grid and charges my batteries then stops charging and goes back on battery after the time period.
 

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