Solar panel help please
- Thread starter gaza2015
- Start date
crossy
Solar Addict
Also, what is your intended battery pack voltage??
At 12V that array will be generating around 130A after the charge controller! (assuming an MPPT controller here)
At 12V that array will be generating around 130A after the charge controller! (assuming an MPPT controller here)
timselectric
If I can do it, you can do it.
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- Feb 5, 2022
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- 19,120
Correct
12v going to get 8 100amps
Why would I be getting 130 amps
crossy
Solar Addict
1600W (4 x 400W) of panels.
1600W at 12V (lowest battery voltage) after the magic of the MPPT = 1600/12 = 133.333A from your controller to your pack.
That's a pretty meaty controller, maybe consider using 2 smaller ones each with a 2S panel connection?
crossy
Solar Addict
Any particular reason for going 12V?
At that power level 24V or even 48V would reduce the currents to more sensible levels. Thinner / cheaper wiring, less critical of volt-drop on your breakers / fuses and connections generally.
Assuming LiFePO4, your pack of 8 X 100Ah batteries will be storing about 10.6kWh of energy.
At that power level 24V or even 48V would reduce the currents to more sensible levels. Thinner / cheaper wiring, less critical of volt-drop on your breakers / fuses and connections generally.
Assuming LiFePO4, your pack of 8 X 100Ah batteries will be storing about 10.6kWh of energy.
I'm new to this I thought the amp on the back of solar panels was the amp that comes down to controller
crossy
Solar Addict
It is TO the controller.
But the MPPT works magic and converts the high-voltage, low current input into a low-voltage, high current output FROM the controller.
Watts (Volts x Amps) in from your panels = (ignoring losses) Watts (Volts x Amps) out to your battery pack.
Dead clever these charge controllers.
So, as an example:-
Say your 1600W of panels are generating 10A at 160V (it's rarely actually going to achieve this, but this is an example).
<MPPT Magic Here>
Your battery pack is going to want about 14V to charge. Your 1600W at 14V is about 115A which is what your battery pack gets.
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rodrick
Free energy enthusiast
At 85 volts unless you live in a tropical area you will have a over voltage problem when the temperature drops and the panels produce more voltage you need to be sure of the temperature compensation factor
crossy
Solar Addict
You might want to go with the 150/70 for a little more safety margin, to ensure you're not going to slip over the maximum PV voltage on cold mornings.
Bluedog225
Texas
- Joined
- Nov 18, 2019
- Messages
- 3,061
You can save a chunk of change by getting your entire system sorted before buying anything else. Lay out your plans here and folks can help. Sounds like you have already outgrown a 12 volt system.
rodrick
Free energy enthusiast
If you run 2p you could run a 150/60 and you would need 2 scc
If you run 2s2p you would need a 250/100 and only require 1scc but you would be over paneled quite a bit
If you run 2s2p you would need a 250/100 and only require 1scc but you would be over paneled quite a bit
On 150/60 be over volts 170.6 as using 2p volts go.up.amps stop same each vog is 80.3v
rodrick
Free energy enthusiast
Parallel volts stay the same amps go up in series volts increases amps stay the same
Ye that's right
