Switch combiner box to serial (3P2S)

[ElFred]

Hello all, I have tree 480w panels, connected to a combiner box.... But, Now, I'm adding 3 others panels (460w)... I need to plug them like this, 3 x 480w in parralel, 3 x 460w in parralel, then, both in serial... But the combiner box is in parallel.... With 4 circuit breaker rated at 32amp. (I'll get 31.86 amp from both set of 3 panels)...

How should I modify the combiner box to make it serial instead parralel ? AND, Which circuit breaker should I buy to do that ?

Thanks


Fred

 

[chrisski]

I’m assuming you are going 3p 2s because the two different panels have nearly matching voltages and amperage?

Could be wired similar to this 2p3s battery, but adapted to 3p2s. I’m seeing you’d need a second combined box for OCP.

 

[ElFred]

I'm going

I’m assuming you are going 3p 2s because the two different panels have nearly matching voltages and amperage?

Could be wired similar to this 2p3s battery, but adapted to 3p2s. I’m seeing you’d need a second combined box for OCP.

View attachment 213936

Hi, I'm going 3p2s because of two set of differents pannels in fact, and it's the only way that I can go... Because my growatt inverter is limited to 145v, so I can not plug them all in series because of that. And the less loss that I have is with 3p2s...

 

[chrisski]

Hi, I'm going 3p2s because of two set of differents pannels in fact, and it's the only way that I can go... Because my growatt inverter is limited to 145v, so I can not plug them all in series because of that. And the less loss that I have is with 3p2s...

Would you mind sharing the specs on the panels? VOC, VMP, ISC, IMP.

 

[ElFred]

Here are the specs of my panels:

Set #1 of 3 QPeak 480W

VOC	53.61​
VMP	44.81​
ISC	11.26​
IMP	10.71​

Set #2 of 3 Jinko 460W

VOC	51.9​
VMP	43.32​
ISC	11.35​
IMP	10.62​

 

[ElFred]

I'll ask the question differently to make it simpler...

Can I simply connect my 3 + from my set #1, then the 3 - from this same set of panels, together with junction boxes... To make it Parallel. Do the same thing with the set of panels # 2, sent both in a 8 AWG, then plug - from set #1 and + from set no 2, then the other + - directly to a 40amp circuit breaker, to make it serial ??? Then sent it to a 4 AWG... It is exactly my goal, but I don't know which hardware to use... I understand that my junction box will no longer do what's it supposed to do, as it will only hold my 40 amp breaker... But that'S not my concern here...

I would like your opinions on this...THANKS

And see the picture with that online calculator, it's why I want to connect my panels like that...

 

[ElFred]

If only I could switch the combiner box from Parellel to Serial with a little jumper or something like that, it would be perfect ! (Someone already told me that was the way to go, but he did not show me how to do it)...

 

[chrisski]

There’s some math in my signature block about mixing panels in series and parallel.

I have not done the math yet, but your panels are so close I think you can put an old one and new one in series and put 3 of these in parallel with little loss. This will be no change to the combiner box.

 

[ElFred]

Thats's what I want.......

 

[ElFred]

There’s some math in my signature block about mixing panels in series and parallel.

I have not done the math yet, but your panels are so close I think you can put an old one and new one in series and put 3 of these in parallel with little loss. This will be no change to the combiner box.

View attachment 216238

The two sets of panels are too far away.... I cannot see how I can apply your fix, if I can, because of the wire price.............. It would cost me a lot of money to wire them like that......

 

[ElFred]

BTW, the new panels are on a solar tracker... And I hope that theses 3 panels will produce even when the 3 others are not producing... IT'S why I'm thinking that there is only one way to connect them, and it'S 3P2S....

I'm ready to connect all that's stuff, but cannot get HELP to make it right............ And I don'T speak english really well, I'm not able to explain exactly what I need... + I'm in a wheelchair, really not easy to do all that's stuff by myself... I'm so frustrated.........

Here is my installation: