On 2024/01/29 at 7:02 PM, Scorp007 said:

All 8 in series is within the peak range on 1 MPPT. Using 4 per MPPT you will fall quite a bit below 200V at times and have a low output. 

8 in series will give a far better yield and even more so on cloudy days. 

Hello, 

 

I wanted to use the JA 545W on my Deye 5kw which has a VOC of 49.75 and Amp of 13.04. 

Option A - 8x in series on single MPPT facing North

Option B - 4x in series on MPPT 1 facing East and 4x in series on MPPT 2 West. 

This is JHB..

Question: Which would be better option?

Edited February 4, 20242 yr by Solarcrazy

28 minutes ago, Solarcrazy said:

Hello, 

 

I wanted to use the JA 545W on my Deye 5kw which has a VOC of 49.75 and Amp of 13.04. 

Option A - 8x in series on single MPPT facing North

Option B - 4x in series on MPPT 1 facing East and 4x in series on MPPT 2 West. 

This is JHB..

Question: Which would be better option?

Option A gives the highest yield per day. 

Option B I can just guess about 15-20% lower but a good yield early in the day in the case of the battery discharged quite a lot during the night and you need to recharge for perhaps a 6-8h LS or even 8-10h LS or even worse a 4h LS cycle 6-10h in stage 4. The same for the west string to get the battery fully charged for night time. 

North tends to have more wasted power during peak production. It all depends on when you use most generated power. This will affect which one is better. 

The drop lower than option A will depend on the direction and angle. 

I can just supply real data for north based on my 5yr stats if all the PV is used. My average throughout the yr comes to 5kWh per 1kW panels installed in Gauteng. My winter yield is also not much lower due to full sunshine days with no cloud even if the day is shorter. 

Edited February 4, 20242 yr by Scorp007

23 hours ago, Scorp007 said:

Option A gives the highest yield per day. 

Option B I can just guess about 15-20% lower but a good yield early in the day in the case of the battery discharged quite a lot during the night and you need to recharge for perhaps a 6-8h LS or even 8-10h LS or even worse a 4h LS cycle 6-10h in stage 4. The same for the west string to get the battery fully charged for night time. 

North tends to have more wasted power during peak production. It all depends on when you use most generated power. This will affect which one is better. 

The drop lower than option A will depend on the direction and angle. 

I can just supply real data for north based on my 5yr stats if all the PV is used. My average throughout the yr comes to 5kWh per 1kW panels installed in Gauteng. My winter yield is also not much lower due to full sunshine days with no cloud even if the day is shorter. 

So I went on the roof today to measure to see how many panels I can actually fit.

On the North side I can fit 6 panels max

On the NE side I can fit about 4 panels Max.

So Option A would be 6 panels North

Option B - 4 panels North and 4 panels NE.

Which option would yield the best?

32 minutes ago, Solarcrazy said:

So I went on the roof today to measure to see how many panels I can actually fit.

On the North side I can fit 6 panels max

On the NE side I can fit about 4 panels Max.

So Option A would be 6 panels North

Option B - 4 panels North and 4 panels NE.

Which option would yield the best?

Sorry to butt in here, we need to know how many degrees NE is your roof direction because if 25° NE will yield more in the afternoon compared to 66° NE so if you can indicate the true NE direction it will help determining the best yield but i personally will go for Option B.

2 hours ago, TaliaB said:

Sorry to butt in here, we need to know how many degrees NE is your roof direction because if 25° NE will yield more in the afternoon compared to 66° NE so if you can indicate the true NE direction it will help determining the best yield but i personally will go for Option B.

How do I check the degrees you speak of in your comment? 

29 minutes ago, Solarcrazy said:

How do I check the degrees you speak of in your comment? 

I think @TaliaB is looking if NE is at 45 degrees or more north or more east of the 45 degree.

Your option B with 8 panels should yield more if NE is at 45 degree or any angle towards north. 

You can also look on Google maps and use the satellite layer. North is normally at the top of the screen display. 

Edited February 5, 20242 yr by Scorp007

31 minutes ago, Solarcrazy said:

How do I check the degrees you speak of in your comment? 

I use an digital compass for my assesments to determine the true direction.

 

3 minutes ago, TaliaB said:

I use an digital compass for my assesments to determine the true direction.

 

Aha, I will check and advise....

On 2024/02/05 at 10:17 PM, Solarcrazy said:

Aha, I will check and advise....

So I now went on the roof and measured etc...This is the final options available to me.

North 359 - space for 5 panels

NE43 - space for 2 panels

E90 - space for 4 panels.

 I was leaning towards 5 panels in the North and 3 panels on the E side so I get some quick morning charge up of my batteries and after 2/3pm the North side only should run? 

@Scorp007 @TaliaB

Question: Which config would be best? I wanted to put about 8 X 545W panels on a 5kw inverter.

 

 

Edited February 10, 20242 yr by Solarcrazy

4 hours ago, Solarcrazy said:

So I now went on the roof and measured etc...This is the final options available to me.

North 359 - space for 5 panels

NE43 - space for 2 panels

E90 - space for 4 panels.

 I was leaning towards 5 panels in the North and 3 panels on the E side so I get some quick morning charge up of my batteries and after 2/3pm the North side only should run? 

@Scorp007 @TaliaB

Question: Which config would be best? I wanted to put about 8 X 545W panels on a 5kw inverter.

 

 

You will have to do 4 panels East 3 panels will be below the mppt startup voltage of 150v. 5 North 5S1P on MPPT1 and 4 East 4S1P on Mppt2 

27 minutes ago, TaliaB said:

You will have to do 4 panels East 3 panels will be below the mppt startup voltage of 150v. 5 North 5S1P on MPPT1 and 4 East 4S1P on 

The VOC of the panels is 49.4.. This means that 9 panels would be 444V..is this not too close to the max voltage? 

Edited February 10, 20242 yr by Solarcrazy

2 hours ago, Solarcrazy said:

The VOC of the panels is 49.4.. This means that 9 panels would be 444V..is this not too close to the max voltage? 

Your maxim dc input on each mppt is 500v. So Mppt1= 5x 49.4v=247v and Mppt2 = 4x 49.4v= 197.6v

7 hours ago, Solarcrazy said:

So I now went on the roof and measured etc...This is the final options available to me.

North 359 - space for 5 panels

NE43 - space for 2 panels

E90 - space for 4 panels.

 I was leaning towards 5 panels in the North and 3 panels on the E side so I get some quick morning charge up of my batteries and after 2/3pm the North side only should run? 

@Scorp007 @TaliaB

Question: Which config would be best? I wanted to put about 8 X 545W panels on a 5kw inverter.

 

 

I have slightly different view to TaliaB but it is not qualified with any calculation so it is more a guess. 

5S1P for the North on MPPT. 

NE 2S and these in series with the 4 panels E90 to give 6S1P connected to MPPT. This string one will need to work out how much the 4xE90 will throttle the 2xNE42 in the after 12h00. This string get you to just below Voc=300V.

The N359 should deliver the bulk of your yield daily summer and winter. 

Edited February 10, 20242 yr by Scorp007

35 minutes ago, Scorp007 said:

I have slightly different view to TaliaB but it is not qualified with any calculation so it is more a guess. 

5S1P for the North on MPPT. 

NE 2S and these in series with the 4 panels E90 to give 6S1P connected to MPPT. This string one will need to work out how much the 4xE90 will throttle the 2xNE42 in the after 12h00. This string get you to just below Voc=300V.

The N359 should deliver the bulk of your yield daily summer and winter. 

Sorry Guys, do not understand the terminology 5S1P, 6S1P etc...

20 minutes ago, Solarcrazy said:

Sorry Guys, do not understand the terminology 5S1P, 6S1P etc...

We use this to indicate it is just 1 string in series. If we use 5 in series and add another 5 in series in parallel with the 1st 5 we write it as 5S2P.