What else do I need to get this going?

[KBurns]

Hello, I've been signed up for a little while, going through some of the categories, and still feel like I'm reading a foreign language. I'm not sure which question to ask first, so here goes.

Will recommended these wires on his web page, but I'm not sure if those are the sizes I will need. Plus, with this crazy world we're living in, I'm kinda in a hurry just to get everything I'll need into my possession.

Wires:

https://www.amazon.com/gp/product/B01F32MM46/ref=ox_sc_act_title_3?smid=A2TN19FHI2Z5KL&psc=1

https://www.amazon.com/gp/product/B01L6OU74M/ref=ox_sc_saved_title_7?smid=A2TN19FHI2Z5KL&psc=1

The system:
HYBRID LV5048 Split Phase 120V/240V output 5kW 48V

HYBRID LV5048 Split Phase 120V/240V – replaced by LV6048 – Watts247.com

watts247.com

I had a difficult time finding, then deciding which numbers to use from the specs from the inverter box.

Two batteries:

24V – A123 LiFePO4 Battery Box – BigBattery.com

bigbattery.com

Twenty solar panels:
Rated Power: 250W
Open circuit voltage (VOC): 37.6 V
Max power voltage (VMP): 30.3 V
Short circuit current (ISC): 8.85 A
Max power current: 8.27 A
Power Tolerance 0/+3%
Maximum system voltage: 600V (UL)
Fuse Rating: 15 A
I also had a hard time trying to figure out which set of numbers to use on these panels.

On his recommendation I also bought these things:
MM400 Multimeter
CL380 Electrical Tester

If anyone finds it easy to know what else I might need without having to be in front of this pile, please chime in. Also, I might have more than I need. After looking at a thousand videos and articles, (and still don't know what the heck I'm doing) I've come to believe my panels will have to be laid out 4 together in series, and then have those 4 in parallel. If that sets anyone's alarm bells ringing, please chime in
Also, I don't know if I'm counting right, so maybe I have too many volts?

Thanks

 

[mopat]

I believe the maximum DC input voltage for your LV5048 is 145 volts.
Four of your panels in series can produce (4 x 37.6) x 1.2 = 180.5 volts; not good.
1.2 is a low temperature correction factor.
You will have to limit panels to 3 in series (3 x 37.6) x 1.2 =135.5 volts; OK, now.

Your batteries have a nominal capacity of 93Ah. The manual for the LV5048 states "It’s suggested to connect at least 200Ah capacity battery for 5KW model."

 

[KBurns]

I didn't notice a low temperature correction factor. I have read that cold panels produce more energy; is that what you mean? Also, would that still apply to Tucson, Az. weather where it's hot year round except for about two days?

So, my batteries that aren't even taken out of the boxes yet, are not powerful enough for the LV5048? Does the amperage remain the same no matter how the batteries are connected?

Thank you. I appreciate you, especially if I don't have to put myself through more turmoil than is needed.

 

[mopat]

Cold panels produce more energy; is that what you mean? Yes.

Would that still apply to Tucson, AZ ? Yes. City does average 17 days a year when the temperature drops below the freezing mark of 32 degrees. Coldest day on record was 6.

Batteries not powerful enough for the LV5048? Correct, capacity too low. Have not studied these batteries but they appear to advertise a capacity of 92.8 Ah @ 24volts. , while the LV5048 is a 48volt system so you will need 2 in series to get 48 volts. So with 2 in series you have 92.8Ah @48 volts. At least 200Ah is still recommended. Review Appendix I (page 31) of the LV5048 manual--it provides backup power duration for 200Ah and 400Ah batteries.

Does the amperage remain the same no matter how the batteries are connected? Amperage (amps) is a measure of current. Here we are talking about battery capacity (amp hours). Your battery is rated to deliver 92.8 amps (current) for 1 hour. If you were to add two more identical batteries in parallel their capacity would add and you would then have 185.6 Ah of battery capacity.

I know you have a lot on your plate but your original post says you have 20 panels and were going to arrange them 4S4P; that's 16, what were the other 4 panels for?
You do realize the LV5048 has two PV inputs, correct?

So maybe think about 3S3P x 2; and have only two panels left over?

 

[MisterSandals]

I didn't notice a low temperature correction factor. I have read that cold panels produce more energy; is that what you mean?

The correction factor is a general guideline.
The thermal coefficient should be on your panels or in the specs.
The Voc is rated for 25 deg C. So you can do the math with your thermal coefficient and the lowest temperature (deg below 25 de C) that you want your system to handle.

Your thermal coefficient should be around .4.
So a temperature drop of 10 deg C (below 25C) would result on a 4v increase per panel.

Do the math with your numbers and temperatures. You will probably find a 1.2 factor about right.

You just need to be certain to NOT exceed your SCC’s input voltage limit.

EDIT: my calc for volts increase above is wrong. The correct way to use thermal coefficient:
>>
Most solar panels have a temperature coefficient of around -0.3% / °C to -0.5% / °C. For example, SunPower's solar panels all have a temperature coefficient of -0.37% / °C. What this means is that for every 1°C above 25°C, SunPower's solar panels decrease in efficiency by 0.37%.
>>