Wiring for East / West Solar array

[bryhan67]

Day time I have a 100 panels flat so getting batteries full is no problem. I want max out sunrise and sunset because its so hot here we need Air Condition 24/7 in the summer.

My question is how the panles are wired. I have 12 panles to work with. 6 east and 6 west. For voltage I put three in series then both sets of 3 in parallel. Then I will put 2 strings east and 2 strings in parallel?

I keep reading put in parallel will work. But is it ok to have each string of 3 panles in parallel.

I have a Midnite solar Classic 150v . I have Jinko 315w VOC on my panles is 46.2.

 

[rodrick]

If your asking if 3s2p will work the answer is yes but your voc voltage is 138.6 which is very close to max voltage on the scc cold temperatures could put you over very easily 2s2p would be my suggestion

 

[Warpspeed]

I have a system very much like this, I have 4S 2P east, and 4S 2P west.
I directly parallel the two east facing groups (as they should behave identically).
And directly parallel the two west facing groups.

However, east and west facing outputs will not be the same, except right at mid day, where they contribute equally.
So each goes through a series diode before being combined, and going into the same solar controller.
The solar controller outputs pretty much constant power throughout the entire day, and works right from sunrise to sunset.

You get less total watt hours per day, but get a very flat power curve for the whole entire day.
In conditions of total cloud cover, all the panels will work equally well, whichever way they face. But straight up is very slightly better.
It should work very well for you.

 

[SamDeleted]

Another good option is two mppts , one for east, one for west . Not strictly necessary but can be simpler

 

[robby]

Another good option is two mppts , one for east, one for west . Not strictly necessary but can be simpler

Yep a separate SCC with two mppts to handle the East and west panels separatel.

 

[bryhan67]

If your asking if 3s2p will work the answer is yes but your voc voltage is 138.6 which is very close to max voltage on the scc cold temperatures could put you over very easily 2s2p would be my suggestion

We rarely get below 60 Deg here. I have 5 Midnite solar classis now and been here many seasons.

I have a system very much like this, I have 4S 2P east, and 4S 2P west.
I directly parallel the two east facing groups (as they should behave identically).
And directly parallel the two west facing groups.

However, east and west facing outputs will not be the same, except right at mid day, where they contribute equally.
So each goes through a series diode before being combined, and going into the same solar controller.
The solar controller outputs pretty much constant power throughout the entire day, and works right from sunrise to sunset.

So your east string in its self is in series correct? Then both strings are parallel? What this Diode?Im not worried about a flat curve through the day. I have a 100 panles flat on my garage so im fine there. Not worried about less power for a full day. All I want is pull in max sun and Sunrise and Sunset so I use less battery overnight. All day I make the house as cold as I can then when the sun is gone i shut it all off and keep one small AC running.

Yep a separate SCC with two mppts to handle the East and west panels separatel.

Thats obvious 2 mppts can do it. Question is can one do it? Its like if you get shading on one panel in parallel the others keep generating power right?

 

[SamDeleted]

Thats obvious 2 mppts can do it. Question is can one do it? Its like if you get shading on one panel in parallel the others keep generating power right?

Yes you can just parallel east and west strings into one mppt

 

[bryhan67]

Yes you can just parallel east and west strings into one mppt

And the strings can be in series correct?

 

[efficientPV]

Series connected bad mistake. Parallel them if each array same voltage.

 

[SamDeleted]

And the strings can be in series correct?

Yes or parallel, or series/parallel


The only thing to consider is all panels in any one string (series) have to be facing the same direction/ angle

 

[bryhan67]

Yes or parallel, or series/parallel


The only thing to consider is all panels in any one string (series) have to be facing the same direction/ angle

Yes thats what thought also. Its a combination of Series and Parallel

Series connected bad mistake. Parallel them if each array same voltage.

That's incorrect information I think?

 

[bryhan67]

From what I understand this is how the parallel/series combination will work.

East config
3 panles in series 1st string
3 more panels series 2nd string
Combine 1st & 2nd strings in parallel

West
3 panles in series 1ststring
3 more panels series 2nd string
Combine 1st & 2nd strings in parallel

Then take both East and West and wire parallel to one MPPT.

 

[SamDeleted]

From what I understand this is how the parallel/series combination will work.

East config
3 panles in series 1st string
3 more panels series 2nd string
Combine 1st & 2nd strings in parallel

West
3 panles in series 1ststring
3 more panels series 2nd string
Combine 1st & 2nd strings in parallel

Then take both East and West and wire parallel to one MPPT.

That's how I'd do it


With 4 strings in parallel you need to fuse each string

 

[SamDeleted]

There might be problem if the panels were different volts/amp/watts , or different amounts of panels

, but you're matching them up identically so should be perfect fine

 

[SamDeleted]

Get back to us with results

I bet you'll get an extra hour of production morning and night ,

Would be interesting to see the difference in battery consumption before and after

 

[bryhan67]

There might be problem if the panels were different volts/amp/watts , or different amounts of panels

, but you're matching them up identically so should be perfect fine

Yes all exact the same. I will try and track how much longer I can not dip into the batteries. Panels are cheap and last forever. If it works I might double up.

Get back to us with results

I bet you'll get an extra hour of production morning and night ,

Would be interesting to see the difference in battery consumption before and after

Midnite solar has a nice desktop app and can see good history on a good visual chart.