Hi. New to the forum - apologies if it has been discussed to death before and I just couldn't find the thread...

I'm located in gauteng and yesterday 20/11 was hot, sun all day, no clouds, but dismall solar production - top generation peak approx. 0.8 kwh.  Today is cool and overcast and production is stellar - peaking at approx. 1.8 kwh.

Would high temperature alone possibly cause this big of a difference?  

5 minutes ago, mien said:

Hi. New to the forum - apologies if it has been discussed to death before and I just couldn't find the thread...

I'm located in gauteng and yesterday 20/11 was hot, sun all day, no clouds, but dismall solar production - top generation peak approx. 0.8 kwh.  Today is cool and overcast and production is stellar - peaking at approx. 1.8 kwh.

Would high temperature alone possibly cause this big of a difference?  

Not that huge a gap - my max production today is 6.1kwh but on Sat i think i got 5.8kwh - what is the makeup and size of your array (number of panels and the watts) and how is it connected to your inverter?

As mentioned, without the array details it is hard to guess what a reasonable yield would be.
But with a difference like that it sounds like more than just hot solar panels. That could very well be a bad MC-4 connector/connection as well.

5kw Deye inverter - 6 x 415w panels - 5.1kw Shoto battery.  Sorry don't know how pannels is connected to the inverter.  This is a new installation done a month ago. Before I contact the installer I just want to gain some knowledge as to possible causes of low charging rates.

Edited November 21, 20223 yr by mien

What are the details of your system?
Are you grid feeding?

Normally (non-grid feed) - your PV generation is limited to what you consume.
Below, at about 11:30am, the battery was full and PV_power dropped to match consumption.
Consumption is below the line.

Edited November 21, 20223 yr by system32

It's grid-tied. 

49 minutes ago, mien said:

It's grid-tied. 

on the images you posted above can you add the battery SOC so we can see what that was at that time?

28 minutes ago, mzezman said:

on the images you posted above can you add the battery SOC so we can see what that was at that time?

Here are some sceenshots of today and yesterday with SOC added.  Usage and generation is blue and red with SOC overlay.

Yesterday's soc spike around 16:00 was me charging battery from grid to prepare for loadshedding and being able to run aircons during loadshed if needed.

9 hours ago, mien said:

Sorry don't know how pannels is connected to the inverter

On the SolarMan app, go to 'Devices' and then select your inverter. On the new page that opens up, go to 'Statistics and then click on the graph. This will open a new screen, where you can click on 'Parameter Selection'. There, select 'DC Voltage PV1' and 'DC Voltage PV2'. On the resulting screen you will be able to see if your panels are connected in 1 string (only voltage showing on one of the above) or 2 string (voltage showing on both).

Maybe post a screenshot of that graph here, so that we can see what voltage your string(s) run at.

Overall your productions seems low to me (assuming that you do not have shading on any of your panels)

@wolfandyscreenshots for those 2 days as per your directions. Only have pv1 and pv2 - nothing under pv3 etc.  No shading from trees etc.

@wolfandy sorry should have been screenshot of 20 and 21 nov. But 21 nov looks similar to the one for the 20th.

that looks like the installer installed 3 panels on 1 MPPT then 3 panels on MPPT 2 - that voltage is too low to generate anything meaningful. You need to ask your installer to come back and install all 6 panels on 1 MPPT - leaving the other MPPT free for now

Thanks @mien - the screenshot help

1 hour ago, mzezman said:

that looks like the installer installed 3 panels on 1 MPPT then 3 panels on MPPT 2 - that voltage is too low to generate anything meaningful

That was exactly my suspicion. No idea why installers wire things up that way. Makes me wonder how well they actually know their stuff...

1 hour ago, mzezman said:

You need to ask your installer to come back and install all 6 panels on 1 MPPT - leaving the other MPPT free for now

+1

@mien For your understanding - and that you can educate your installer: The MPPT in the Sunsynk has a startup voltage of 150V (as per the Sunsynk spec sheet), which means that the MPPT only starts up when the voltage on your panels reaches 150V. Now it appears that the MPPT actually does seem to start up a around 125V - otherwise you would not be generating any PV at all currently. The max MPPT voltage is 425V, which means your installer can easily combine the strings into a single string (resulting in 260V) and you will still be well within the limits of the MPPT. The other positive effect of this will be that you will start producing PV a bit earlier in the morning (because the 6 panels reach the 125V/150V earlier than your 3 at the moment) and also produce a bit longer in the evening.

You can probably add another 3 panels to that string if you want (finances and roof space allowing).

Only upside out of all of this is that your installer has already pulled 2 sets of cables from your roof to your inverter. So if in future you want to add more panels and put them on your 2nd MPPT, you don't need to pull any additional cables.

@mzezman @wolfandy Thank you for all the assistance and advice. I'll contact the installer and discuss. Thanks.

@mzezman @wolfandy Just some feedback. Installer connected both strings to one mppt and here is the result - full cloud cover and all - very happy - thank you again😁

Edited December 11, 20223 yr by mien
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It is disappointing to hear of installation mistakes like this.

Great to see you getting the full use of your equipment you paid a lot of money for.👍