Adding Panels From Different Manufacture to Array

[JasonAch]

Hi,

I have a Growatt SPF5000ES and I currently have 8x450w Canadian solar panels.
I would like to add more panels but im struggling to find stock of Canadian solar anywhere close to me so I was wondering if I could use Jinko 415w instead as it’s the closest matching panel I could find. I understand that this is not ideal and that I will be sacrificing some of the power the panels could generate in this configuration (about 50w if im correct).

I would like to buy 4 Jinko panels to add to my 8 Canadian panels.
I would then have 2 string. Each string with 4 Canadian and 2 Jinko panels.

From my understanding in series voltage is added up and current comes from lowest panel in your string so
I would end up with an open circuit voltage of 289.94v, an optimal voltage of 237.98v and a current of 10.96a so about 2608w per string.
If I combine 2 string in parallel, I would get a voltage of 237.98v and a current of 21.92a so about 5216w total.

Would this configuration be ok? Are my calculations correct? Is the voltage difference of 41.1v vs 36.79v too large for panels in series?

= Growatt SPF5000ES (Single MPPT)
Max PV Input Current: 18a (22a with a firmware upgrade)
MPPT Voltage Range 120Vdc~430Vdc (450Vdc MAX)
Max PV Array Power: 6000w

= 450w CanadianSolar CS3W-450MS
Open Circuit: 49.1v
Opt Voltage: 41.1v
Opt Current: 10.96a

= Jinko Solar Panel Tiger N-Type 415W Mono-Facial
Open Circuit: 46.77v
Opt Voltage: 36.79v
Opt Current: 11.28a


Thanks.

 

[Hedges]

6s string consisting of 4s Canadian in series with 2s Jinko?

Better to have each string be a single model. If you mix models in series, voltages will add but current will be limited to the one with lower current, as you say (approximate, actual voltage/current response is a curve.)

It is OK to have strings of different models in parallel. To the extent they are somewhat different voltage, MPPT will find the voltage where whole array produces the most power. The power/voltage curve is reasonably flat on top so OK to move a few percent off Vmp.

 

[SamDeleted]

41.1vmp vs 36.79vmp

450w vs 415w

Is it possible to find new panels closer matched to the originals?

 

[JasonAch]

6s string consisting of 4s Canadian in series with 2s Jinko?

Better to have each string be a single model. If you mix models in series, voltages will add but current will be limited to the one with lower current, as you say (approximate, actual voltage/current response is a curve.)

It is OK to have strings of different models in parallel. To the extent they are somewhat different voltage, MPPT will find the voltage where whole array produces the most power. The power/voltage curve is reasonably flat on top so OK to move a few percent off Vmp.

I was thinking 2 string consisting of 4 Canadian in series with 2 Jinko.
So a total of 12 panels (8 Canadian and 4 Jinko).

The main issues is if I keep the models together I cant get them all to a compatible voltage and I will exceed my inverter cut off current of 22a and be wasting power that way.

Same models together:
392v and 10.96a (Canadian 8)
147v and 11.28a (Jinko 4)

Canadian split into 2 strings:
196v and 10.96a (Canadian 4)
196v and 10.96a (Canadian 4)
147v and 11.28a (Jinko 4)

Canadian split into 3 strings:
123v and 10.96a (Canadian 3)
123v and 10.96a (Canadian 3)
082v and 10.96a (Canadian 2)
147v and 11.28a (Jinko 4)

 

[JasonAch]

41.1vmp vs 36.79vmp

Is it possible to find new panels closer matched to the originals?

I am looking, a lot of places seem to be out of stock at the moment.
The only other panels I found so far are lot smaller or bigger like the Jinko 650w.