Please can someone help.
I Have 12 Longi HiM06HTB 435 all black Mono solar panels fitted we then had 4 extra panels fitted [total 16]
We have Fox ESS H1 G2 5.0 kW 1ph Hybrid inverter.
My neighbour has eight panels
AIKO-A460-MAH54Mb 460watt panels
HESS-HY-S-3.6KHybrid inverter .
he has 8 all on one roof i have five on the same roof the rest on three other roofs . both systems have been installed within the last six months.
My concern is.
His 8 panels are out performing my 16 panels by a lot
Example
Sat 3rd
his total yield 8 panels 19.1 my 16 panels was 14.7
exported.
his was13.20 mine was 7.20.
Its the total yield that bothers me surely my 16 panels should draw in more than 8 panels
My installer is saying its all running fine and doing what its supposed to do,
Any help or advice would be very much appreciated.
Regards David Clements.
system
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Dave Foster
- Posts: 1850
- Joined: Thu Oct 13, 2022 7:21 pm
There is a lot to consider here,
are all of your panels in a single string i.e. 16 * 435 watt panels = 6,960 watts which is firstly higher than your inverters output (5kw) but also higher than the recommended power on a single string (3750 watts) - if they are on a single string your inverter will be severely restricting the input power they can generate.
If they are split over 2 strings, how many are on each string ?
You haven't said whether you have optimisers fitted, when you have panels facing different direction you will get different power outputs from each roof across the day - but if you have multiple roofs connected to 1 PV string and no optimisers fitted the roof operating at the lowest power will throttle the power generation of any other roof, even if some are in full sunshine.
The optimal solution by far is to have 1 roof with all panels facing the same direction, if your neighbour has 8 panels pointing in a good direction they will likely get almost perfect output.
It would be helpful if you could post images of your PV1 power and PV2 power graphs for a clear day, that would show how the string is performing and whether the inverter is restricting it or another roofs shade might be holding it back.
are all of your panels in a single string i.e. 16 * 435 watt panels = 6,960 watts which is firstly higher than your inverters output (5kw) but also higher than the recommended power on a single string (3750 watts) - if they are on a single string your inverter will be severely restricting the input power they can generate.
If they are split over 2 strings, how many are on each string ?
You haven't said whether you have optimisers fitted, when you have panels facing different direction you will get different power outputs from each roof across the day - but if you have multiple roofs connected to 1 PV string and no optimisers fitted the roof operating at the lowest power will throttle the power generation of any other roof, even if some are in full sunshine.
The optimal solution by far is to have 1 roof with all panels facing the same direction, if your neighbour has 8 panels pointing in a good direction they will likely get almost perfect output.
It would be helpful if you could post images of your PV1 power and PV2 power graphs for a clear day, that would show how the string is performing and whether the inverter is restricting it or another roofs shade might be holding it back.
Thanks for getting back to me,
All panels have optimizers.
My installers told me 16 panels would be the maximum i could have.
As for single string ,I don't know I will have to ask installers.
When you put your trust in a company you expect the best advice and system.
I will let you know what they come back with.
Regards Dave
All panels have optimizers.
My installers told me 16 panels would be the maximum i could have.
As for single string ,I don't know I will have to ask installers.
When you put your trust in a company you expect the best advice and system.
I will let you know what they come back with.
Regards Dave
Good afternoon , Please see attached two photos of the PV graph, and the Inverter as requested.
Looks like there is two strings, Is this correct for sixteen panels.
Do you think the inverter is sufficient for the system i have.
Regards
David Clements
Looks like there is two strings, Is this correct for sixteen panels.
Do you think the inverter is sufficient for the system i have.
Regards
David Clements
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Dave Foster
- Posts: 1850
- Joined: Thu Oct 13, 2022 7:21 pm
The voltage showing does confirm you have both strings active, I assume that screenshot must have been taken when it was cloudy - with 4 panels you'd expect to see around 120 volts in full sun, and for the 12 panels around 360 volts, but the installer could have wired some of the panels in parallel i.e. 6 || 6 so the voltage would be lower ~ i.e. 180 volts but the current would be much higher.
The answer to the 12 panels on one string being too many question is 'it depends', if you have 12 panels on one roof all with the same elevation the answer would be a resounding yes, the power is too high for the inverter to handle and it will clip in full sun. But as you have different roofs / elevations you may be hitting peak sun on one roof in the morning and peak on the other in the afternoon - the net result being that it will work fine and won't be clipped as the maximum power is never too much to cause problems. Going back to your neighbour, if he has 8 panels pointing in a clear and uninterupted direction that gets sun all day, it is possible that he will get more power than you as they will always be operating at a higher power.
If you use the Foxcloud website and go to the Inverter Details screen (click Device, Inverter and then click the blue search in the operation field) - you will see your device status, energy flow screens and a power /statistics graph - but below that at the bottom of the page is an 'empty' graph - here you can select different sensors to view and compare to see how they change over the day.
If you can select PV1 Volt and PV2 Volt and 'search' it will show how the voltage changes across the day and you can pick which day to view - if you could post that image on a sunny day that would be really helpful. Also if you can choose the sensors PV1Power and PV2Power you will see how the 2 strings produce power across the day, again a very useful graph as if the inverter is clipping the peak power will have a flat top to it rather than a curved peak - again if you could post that graph for a sunny day it would help to see how your system is performing.
The answer to the 12 panels on one string being too many question is 'it depends', if you have 12 panels on one roof all with the same elevation the answer would be a resounding yes, the power is too high for the inverter to handle and it will clip in full sun. But as you have different roofs / elevations you may be hitting peak sun on one roof in the morning and peak on the other in the afternoon - the net result being that it will work fine and won't be clipped as the maximum power is never too much to cause problems. Going back to your neighbour, if he has 8 panels pointing in a clear and uninterupted direction that gets sun all day, it is possible that he will get more power than you as they will always be operating at a higher power.
If you use the Foxcloud website and go to the Inverter Details screen (click Device, Inverter and then click the blue search in the operation field) - you will see your device status, energy flow screens and a power /statistics graph - but below that at the bottom of the page is an 'empty' graph - here you can select different sensors to view and compare to see how they change over the day.
If you can select PV1 Volt and PV2 Volt and 'search' it will show how the voltage changes across the day and you can pick which day to view - if you could post that image on a sunny day that would be really helpful. Also if you can choose the sensors PV1Power and PV2Power you will see how the 2 strings produce power across the day, again a very useful graph as if the inverter is clipping the peak power will have a flat top to it rather than a curved peak - again if you could post that graph for a sunny day it would help to see how your system is performing.