Suggestions with my configuration!

[kamatech]

Hello, some time ago I bought an 8k hybrid inverter with 3 48v EG4-LL Lithium Battery (V2) , I am finishing buying the other parts to be able to assemble my system.

Spec of inverter



spec of battery






I will be using 9 solar panels with the following specifications

ELECTRICAL PARAMETERS
Performance at STC (Power Tolerance 0 ~ +3%)
Maximum Power (Pmax/W) = 550w
Operating Voltage (Vmpp/V) = 41.96
Operating Current (Impp/A) = 13.11
Open-Circuit Voltage (Voc/V) = 49.92
Short-Circuit Current (Isc/A) = 14.00
Module Efficiency nm(%) = 21.2



my setup


3 panels in series to have 1 string per mppt. (inverter have 4 mppt)
What would be the parameters in 3 panels in series

voc= 49.92x3x1.25% = 187.20v
Isc = 14.00x125% = 17.5a


I plan to use 1 breaker of 2 Pole, 20A, 480V AC, 250V DC, Trip Curve: C, DIN Rail Mount-Miniature Circuit Breaker, 35mm Width, UL1077 (SKU: NDB2Z-63C20-2). per series of 3 panels
(https://www.sourceasi.com/product/dc-din-rail-mount-circuit-breaker-2-pole-20-amp-mcb-ul1077/)

additional
DIN Rail Mounted Midget Fuse Holder, 2 Pole, 10 x 38 mm, 18 to 8 AWG, 32 Amp, 1000 VDC, PV Rated, (SKU: AFB01D2P).with 20A fuses. per series of 3 panels.
(https://www.sourceasi.com/product/solar-fuse-holder-2-pole-1000vdc-30-amp-din-rail-mount/)

To protect the batteries I would use
2 Nader DC Circuit Breaker | 60V 200Amp (https://signaturesolar.com/nader-dc-circuit-breaker-60v-200amp/)
one for positive and one for negative

PV connection
Use 10 AWG wire to connect with ferrules.


Grid Connection
Connect the 8 AWG wire to ferrules


Battery connection
2/0 awg




Any suggestions or help you can give me about this configuration would be very grateful. Thanks

 

[Rednecktek]

The only thing that comes to mind is it looks like you're going to be using breakers AND fuses on each PV input line? Is there a reason for the redundancy?

Also, the 8AWG seems a bit small, that inverter can put out 40a per leg so 8AWG is the minimum size, but what's the wire length going to be? Can you step that up to 4AWG (which is the largest size normal AC breakers can accommodate) to give you headroom for wire length and/or future expandability?

 

[kamatech]

The only thing that comes to mind is it looks like you're going to be using breakers AND fuses on each PV input line? Is there a reason for the redundancy?

Also, the 8AWG seems a bit small, that inverter can put out 40a per leg so 8AWG is the minimum size, but what's the wire length going to be? Can you step that up to 4AWG (which is the largest size normal AC breakers can accommodate) to give you headroom for wire length and/or future expandability?

thanks reply ,
Correct, I would use fuse and breaker in each line, I understand for more protection.

The fuses would be located in an electrical box very close to the solar panels, minimum 2 feet. Instead I plan to put the breakers in a room where the inverter and the batteries will be.

distance from the fuses to the breakers we would be talking about 8 feet.

I also plan to put an ac sub panel in the same room as the distance would be about 4 feet. From that sub panel it runs to the manual transfer switch which would be some 15 to 20 feet, from the transfer switch to the main panel less than 10 feet which feeds the house.

That is what I think according to the information that I have been able to read and understand, that is why I ask for suggestions to make a good configuration.

My house is 2 levels, on the second level everything will be set up.


thank you