question

swordoski avatar image
swordoski asked

Parallel-MPPT-System

Something special i should think about with follwing setup
MPPT 75/15 parallel with MPPT 100/20

battery charging
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

3 Answers
JohnC avatar image
JohnC answered ·

That'll be fine Sword. The blue boxes will look better on the wall than those TS ones though.. :)

10 comments
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

swordoski avatar image swordoski commented ·

@JohnC

If i use one PV Array with 2x100w in series and the other PV Array with 2x100w in parallel of course with blue boxes Victron 75/15 MPPT :)

is that ok ?!

0 Likes 0 ·
JohnC avatar image JohnC ♦ swordoski commented ·

@swordoski

Yes, in principle that's ok. But it's nice to have a good difference between strung Vpanel and Vbat. Will perform better in less than optimal conditions.

And stringing '12V' panels parallel into 12V batts mightn't work so well. So look at your panel V's to be sure.

0 Likes 0 ·
swordoski avatar image swordoski JohnC ♦ commented ·

@JohnC

This is the specs of new panels 2x100w


Generator Performance (Wp) 100 Wp

Module Voltage (Vmp) 17,8 V

Max. Current (Imp) 5,62 A

No-Load Voltage (Voc) 21,3 V

Short-Circuit Current (ISC) 6,07 A


This is the specs of old panels 2x100w

Generator Performance (Wp) 100 Wp
Module Voltage (Vmp) 18,0 V
Max. Current (Imp) 5,56 A
No-Load Voltage (Voc) 21,5 V
Short-Circuit Current (ISC) 6,04 A

I was also thinking about this setup as i have some shading during the day






0 Likes 0 ·
2052-sp.jpg (51.3 KiB)
JohnC avatar image JohnC ♦ swordoski commented ·

@swordoski

Yeh, those are '12V' panels, and best strung serially in pairs. Like in your diagram, but weren't you talking 2x mppt's?


0 Likes 0 ·
swordoski avatar image swordoski JohnC ♦ commented ·

Yes i was @JohnC

But with the above diagram i can change to only one blue box ?!

I have not push the order button yet.

I can´t make a decison how to do when i have different options :)
0 Likes 0 ·
JohnC avatar image JohnC ♦ swordoski commented ·

@swordoski

Ha, sure you have options, and what you choose depends possibly on your shade, and even what type of shade. Whether the solid type from a fixed shade pattern, or mottled from tree branches or suchlike. And seasonal patterns enter there too.

Your 4x panels are well matched and you could even string all 4x serially into a single 100/30.

Or go with your diagram and separate into pairs if 2x panels get shade. That will help a little.

Or go 2x 75/15's if there's serious shade difference between the panel pairs.




0 Likes 0 ·
swordoski avatar image swordoski JohnC ♦ commented ·
Thanks @JohnC



I go with my 2x 75/15 and see what’s happens.
One more question.
I have 2 batteries (12v) in parallel should I connect one of the 75/15 to one battery each ?!

0 Likes 0 ·
JohnC avatar image JohnC ♦ swordoski commented ·

@swordoski

If you're using the batts as a group, good practice is to have all your chargers and loads attached to the same terminals/bus.

Good luck with your project..

0 Likes 0 ·
swordoski avatar image swordoski JohnC ♦ commented ·

Thank for your support @JohnC
My setup will be like in the picture :) Where i put both 75/15 to the first battery.
But i was think about the load....
Isn't it better to connect the load to the positive terminal on the first battery and the negative terminal on the second battery ?!

0 Likes 0 ·
mppt-sword.jpg (74.7 KiB)
Matthias Lange - DE avatar image Matthias Lange - DE ♦ swordoski commented ·
0 Likes 0 ·
swordoski avatar image
swordoski answered ·

Then can i do that with 2 different uits ?! 75/15 and 100/20 ?

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

hobohome avatar image
hobohome answered ·

I do this with my system. I have 1x150/100 and 2x150/35.

It works ok, but because the three controllers are not truly networked, they do their own thing.

There was a post here a couple of days ago letting us know that all of that will very soon change (at least for devices that have Bluetooth)... true parallel operation.

Yea!

1 comment
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

swordoski avatar image swordoski commented ·

Okay

And it doesn´t matter which MPPT i put the load output from ?!!

0 Likes 0 ·

Related Resources

Additional resources still need to be added for this topic