Photovoltaic PV connection ???

[chris34]

Thank you Remundo!

I understand quickly ... when you explain me a long time!

In short, your answers do not settle me finally I feel that I will have to split a MPPT 100 / 50! Gloups

[chris34]

Heuuu ... Gaston, why do you say that the 100 / 30 MPPT only supports 720 W?

[Remundo]

the 30A will deliver under 24V 720W to your batteries.

the 50A, 1200 W = 50A x 24A

subject to good sunshine, of course.

multiply the MPPT is justified if you really have to have different orientations of each string, but frankly on 10m ², you should get out no?

One last note, put 4 string of 3 panels // decreases joules losses.

Indeed,
1) a series of 3 strings of 4 panels //: the current is 4 x 4,44A = 18A
2) a series of 4 strings of 3 panels //: the current is 13A

Assuming a substantially identical cable length in the 2 assumption, the Joule losses are decreased by (4 / 3) ² -1 = 77%

Or put it another way, we will have 1,77 more Joule losses with 4 panels // than 3 //, because it makes it pass a stronger current on the main power cables.

[chris34]

OK Remundo, thanks for all your explanations!

hummm you said to me "the 50A, will deliver to the batteries 1200 W = 50A x 24A" ... (ok I have good sunshine!)
but in the end I will have "only" 13A when the regulator arrives, right?

Well, ok for the solution of "a series of 4 strings of 3 panels //: the current is 13A" ... I will need a stock of "Y" connectors (around 16 if I count correctly; O)

Moreover, considering the price of 100 / 50, and since I already have 2 pairs of cables (6 mm²) posed, what would you say (I still abuse!) The solution of 2 regul. 100 / 30 (2 times cheaper than 100 / 50) each powered by a string of 6 PV. (each in 2 segments in // of 3 PV in series) .OuF!

[Remundo]

in fact, your PV field would provide peak power 90V x 13A = 1170 W

So under the assumption [simplifying!] Of a yield of 100% on the regulator, this power passed in 24V generates a current of 1170 / 24 = 48.75 A only

for your new hypotheses, you have to work by yourself, you have understood the system:
1) the voltage range of the regulator must be respected
2) the output current of the regulator must be sufficient
3) the no-load (or cold) voltage of the panels must not exceed the maximum permissible voltage of the regulator

* in parallel: the currents are added, and the tensions are equal

* in series: the currents are equal, and the tensions are added

voila here

[Gaston]

Moreover, considering the price of 100 / 50,
[...]
what would you say about the 2 regulation solution. 100 / 30 (2 times cheaper than 100 / 50)

For me the 100 / 50 costs a little more than 300 € while the 100 / 30 costs a little more than 200 € ...

So 2 100 / 30 controllers are more expensive than 1 regulator 100 / 50.

[Remundo]

and here are some connectivity zinzins PV to make the setting //
https://www.google.fr/search?q=connecte ... d=0CDkQsAQ

PV panels are mainly intended to be put in series ...

also remains the solution: cutting pliers, stripping the cable, braiding the copper strands, and screw everything under a big 16² domino for example ... by cons it is irreversible for the panels.

[chris34]

OK !

I catch the calculator and the pencil from the nap

Thanks again for your lights

[elephant]

Remundo said:

and screw everything under a big domino of 16² for example ... by cons it is irreversible for the panels.

Attention, the regulation (the Belgian, in any case, which is sufficiently demanding) specifies that the connections of the panels must be made in separate boxes for the positive and the negative. If you use a common DB, you need a wafer between the + zone and the - zone. Do not forget that there is no fuse upstream and that in case of short circuit, even if the voltage drops, the current remains high!

[chris34]

OKAY !! thank you thank you guys ...

I think that given the overall costs, I am no longer at qq. copecs for "Y MC4"; O)