diy solar

diy solar

I think i got my system( if this is the right thread!!)

100kwh-hunter

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If it is not on the right section of this forum pleas let me know or move it right away(not (re)move)

After 2 years of studying and experimenting i think i found MY golden match....I think, that is.
I would really appreciate your opinion, thoughts, ideas and comments!!!! and every thing else.
End goal: 9 of the inverters and 90 of those panels.
Use two ev cars, home heating(direct into a water tank, so no cells are in this section of the system) electric cooking light ect.

Home heating:
DERNORD Stainless Steel 48v 1500w Electric Immersion Water Heater DC Heating Element|electric element water heater|element water heaterelement heater - AliExpress
with:
110V 220V 12V 24V Digital Temperature Humidity Controller Thermometer Hygrometer Incubator Dehumidifier Thermostat Humidistat DC|Temperature Instruments| - AliExpress
I orderd this one for my tobacco curing room, they have it also for 48v temp cut of to max 25a(first storage: water well 35C, home heating, second storage: shower bath ect 70C)
Inductive cooking will be implemented!
But this is a different threat(2x)

End goal to get rid of all the roberments connections....

PIP-MGX.pdf (mppsolar.com)
This would be the inverter of my choose...(to build up of course......of course i will start with one and every year i will add one or two more every year!)

Solar pv pannels:
Shop GWL | Solar panel GWL/Sunny Mono 450Wp 72 cells, PERC (ESM-450 Pack 4 pcs)
I think there are a good match, but the amount of panels according to there wp or total Ah deliver gives me some confusion?
Really need some clearance on this and how much panels can i connect to one inverter?????
Please answer this one: hoe much pv i can connect IF they are a match?

Probably not 10 pv panels at each inverter i would like to give them a easy live.
But two times a string of 9 inverter string? if this is possible?
Thought and comments on this is also very welcome and appreciated, many many thanks in advance.

The bms is a other subject: 123smart of gwl or batrium? both are stand alone? and both can handle max 255 units(280ah can be one, two 150 = 300 can be one)
Thoughts and advice on this one is also greatly appreciated.
BMS123 Smart Gen3 - Complete Set (4 cells) with Bluetooth 4.0 | shop.GWL.eu

Basically is the inverter and the panels a good match and how much pv can i connect to one inverter, this i still something dont get, yet.....
Thoughts on the bms???

With best regards Igor K, and thanks in advance

https://shop.gwl.eu/Electric-Cars/?cur=1
Will also a different threat!
Best...

PS i am NO vendor or get money of commercial displaying links....
 
Solar panel spec:
1606954797262.png

PIP-MGX spec:
1606953082677.png

Based on the above specs, you can't do parallel strings, as the solar panel's 'Short-circuit current' spec is 11.88a, because 2 strings multiplies your current up to 23.76a which is over the PIP-MGX's max PV Input Current spec of 18A, so parallel is out the question.

And, based on that solar panel's Voc (volts without load): 49.90v, if you wired 8 of those panels in series, you'd get a total Voc of 399.2v (not correcting for freezing temperature), you are still safely under the MPPT max input Voc of 450v, and that puts you at 3600w max. You can't put 9 panels, as that jumps Voc to 449.1v, so way too much.

So you're pretty much locked into 3600w, 1 series string of 8 panels, using that panel. That's fine if your fine with that...


I assume you are in Europe where Split-Phase (240v/120v) doesn't matter to you, because that PIP-MGX is one voltage, no split-phase...


Thoughts on the BMS? I can't really answer much to that one, it looks really interesting though, looks like a scaleable BMS where you just add more modules in between the start module and end module, and can scale to any size, and uses a master relay for bank cutoff. Maybe someone else has tried this setup and knows more about it.

I had been wondering about building a 56-cell bank before to match my Prius battery, but wondered where to find a BMS which supports 56s. I wonder if this BMS would work for 56s, and 3.6-3.7v cell?
 
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Based on the above specs, you can't do parallel strings, as the solar panel's 'Short-circuit current' spec is 11.88a, because 2 strings multiplies your current up to 23.76a which is over the PIP-MGX's max PV Input Current spec of 18A, so parallel is out the question.

You could do two parallel strings, each 8 panels in series, if the two strings had different orientations.
Facing the same direction, current would reach 23.7A
But if facing 90 degrees apart, for instance at 9:00 AM and 3:00 PM sun, current would peak 0.7 times as high, 16.6A
With power spread over more hours, less cycling of battery.
 
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You could do two parallel strings, each 8 panels in series, of the two strings had different orientations.
Facing the same direction, current would reach 23.7A
But if facing 90 degrees apart, for instance at 9:00 AM and 3:00 PM sun, current would peak 0.7 times as high, 16.6A
With power spread over more hours, less cycling of battery.

Yeah that's true, I heard you mention that concept before, I didn't think about that strategy when I had posted that, was just thinking one dimensional. Good thing we have lots of perspectives here in the forum to keep us in check... (y)
 
Thanks for all the replays, i will get around it and give you a decent replay, many thanks
Cheers...its Friday
 
Solar panel spec:
View attachment 29160

PIP-MGX spec:
View attachment 29159

Based on the above specs, you can't do parallel strings, as the solar panel's 'Short-circuit current' spec is 11.88a, because 2 strings multiplies your current up to 23.76a which is over the PIP-MGX's max PV Input Current spec of 18A, so parallel is out the question.

And, based on that solar panel's Voc (volts without load): 49.90v, if you wired 8 of those panels in series, you'd get a total Voc of 399.2v (not correcting for freezing temperature), you are still safely under the MPPT max input Voc of 450v, and that puts you at 3600w max. You can't put 9 panels, as that jumps Voc to 449.1v, so way too much.

So you're pretty much locked into 3600w, 1 series string of 8 panels, using that panel. That's fine if your fine with that...


I assume you are in Europe where Split-Phase (240v/120v) doesn't matter to you, because that PIP-MGX is one voltage, no split-phase...


Thoughts on the BMS? I can't really answer much to that one, it looks really interesting though, looks like a scaleable BMS where you just add more modules in between the start module and end module, and can scale to any size, and uses a master relay for bank cutoff. Maybe someone else has tried this setup and knows more about it.

I had been wondering about building a 56-cell bank before to match my Prius battery, but wondered where to find a BMS which supports 56s. I wonder if this BMS would work for 56s, and 3.6-3.7v cell?
Thank you very much for your replay!

Yes i am in the Netherlands and indeed we use single fase.
In the near future i would like to buy two more to connect them for 380v.
Buy also some solar charger from victron to add more panels and more cells afcourse.
Our official cold number is 12.6%

Those first 8 panels are going on a roof on the ssw located.
The roof of the shed is dead south located and 120m2.
On this roof will be other panels:
I am in doubt to buy:
285wp voc 38,5v, 9.5a or
310wp voc 40,0, 10,0a or
330wp voc 41,3v, 10,3a
With combination of the victron charger 150v/45a max nominal 2600w
In 3s3p will give the 285wp a safe 2565w
In a 3s3p will give the 330wp a 2970watts a bit to much?
with the 310wp it will give 2790watts

Thanks in advance and for thinking with me, best Igor
 
Thank you very much for your replay!

Yes i am in the Netherlands and indeed we use single fase.
In the near future i would like to buy two more to connect them for 380v.
Buy also some solar charger from victron to add more panels and more cells afcourse.
Our official cold number is 12.6%

Those first 8 panels are going on a roof on the ssw located.
The roof of the shed is dead south located and 120m2.
On this roof will be other panels:
I am in doubt to buy:
285wp voc 38,5v, 9.5a or
310wp voc 40,0, 10,0a or
330wp voc 41,3v, 10,3a
With combination of the victron charger 150v/45a max nominal 2600w
In 3s3p will give the 285wp a safe 2565w
In a 3s3p will give the 330wp a 2970watts a bit to much?
with the 310wp it will give 2790watts

Thanks in advance and for thinking with me, best Igor

Assuming the battery voltage will be 48v (based on the 2600w)... You can go over on the watts spec (won't blow it up or anything), but the Victron charger just won't harvest anything over that max watt amount. Also note, your solar panel specs may be based on SLC or NOCT ratings, if it's SLC, then those wattages are based on numbers you may not likely see too much in the real world, unless you have perfect angle, perfect sun, with perfect temperature. The ratings you get with NOCT should be more conservative, and may total up to lower watts.

1607530552721.png

1607530577629.png
 
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