@Tariq What size arrays are you running now? 

NNW array is 6 JaSolar 540 watt panels, NNE array is 9 Canadian Solar 355 watt panes, for a total of 6435 watts. 

@hussein,  you sure can, you can easily go up to 10 panels on each string, just make sure the firmware is updated to be able to go up to 22 amps

5 hours ago, Tariq said:

@hussein,  you sure can, you can easily go up to 10 panels on each string, just make sure the firmware is updated to be able to go up to 22 amps

Thank you

9 hours ago, Nexuss said:

Thanks @Tariq that is what i suspected , at 370 volts the mppt would be running at about 87%. Think i read somewhere that the best for efficiency is like 80% so that would indeed make sense. Quite interesting about the voltage peaking on a cold day . I have not found that at all during the past winter ,monitoring the voltages of my panels for a while now and they dont peak in volts on cloudy days but they do peak in amps. The highest voltages i get is when the panels are idling during the day. 

Highest voltage when it is really cold and the sun comes out from behind the clouds at peak solar time.

8 hours ago, branderplank said:

So the inverter can only ever invert 8kw. Is the balance of power generated going to the battery? Did not know it can exceed 8.8kw on the DC Bus? Or would it be limited to the 10.4kw max solar PV input?

Max in the settings is 12kw,  maximum it can invert is 8kw, rest goes to the batteries. 

2 hours ago, Sc00bs said:

Highest voltage when it is really cold and the sun comes out from behind the clouds at peak solar time.

I have checked in that exact conditions and the voltages dont peak only the amps . I wonder if its not cold enough in cape town ?

So if he had 18 panels he can connect  9 panels per MPPT as long as the software has been updated ?

@Morne SBRyes, that is correct

@Nexuss, i am based in Cape Town also, my one string is 355 watt panels times nine

Voc 421 volts

Vmp 354 volts

the max I saw this winter is 411 volts

Thanks 

have you guys noticed that as the panels get larger the Voc is dropping, eg

Canadian Solar  355 watts  46.8 volts

Canadian Solar 595 watts  41.1 volts

47 minutes ago, Tariq said:

have you guys noticed that as the panels get larger the Voc is dropping, eg

Canadian Solar  355 watts  46.8 volts

Canadian Solar 595 watts  41.1 volts

The 595 panels are smaller than the Ja 540w

Canadian Solar 2172 X 1303 

  JaSolar           2279 X 1134

so the JaSolar is slimmer by 149 mmm, which might be more important depending on your roof width 

@husseinis your system running ?

Edited October 15, 20214 yr by Morne SBR

 

The is the maximum I have had on my array so far. 

All excess power goes to the battery, so if my inverter is generating 8kw of AC, it would be sending 3.9kw to the battery. 

The way I see it, panels are relatively cheap, on sunny days there isn't really much of a benefit as a lot of the power I have available is not used, but on more overcast days and in winter when they isn't so much solar energy and I would be pulling power from Eskom with my smaller array, I should still have loads of extra power available.

I am also putting a pool heater in this year which will pull 3kw for when I have nothing else to do with the power 🙂 

53 minutes ago, Sc00bs said:

 

The is the maximum I have had on my array so far. 

All excess power goes to the battery, so if my inverter is generating 8kw of AC, it would be sending 3.9kw to the battery. 

The way I see it, panels are relatively cheap, on sunny days there isn't really much of a benefit as a lot of the power I have available is not used, but on more overcast days and in winter when they isn't so much solar energy and I would be pulling power from Eskom with my smaller array, I should still have loads of extra power available.

I am also putting a pool heater in this year which will pull 3kw for when I have nothing else to do with the power 🙂 

What size solar array have you got 

2 hours ago, Morne SBR said:

What size solar array have you got 

28 x 455w panels, East West split 12 740W