Your battery needs sized to 5 day capacity, which in practice gives you about 3 days with clouds before you must shut down and fully recharged. 5 day sis used to get the most bang from your battery dollars, and CYA for a couple of cloudy days. Ar 4t AH is only 516 wat hours, not enough to CYA for 1 cloudy day. You never ever want to discharge your battery more than 50%.
Solar panel power must meet 2 conditions.
1. To replace what was used in a day under worse case conditions of winter short days. In your case 360 watt hours. That means the panels must generate either 720 watt hours with a PWM controller, or 550 watt hours for a MPPT system.
2. Must meet minimum Charge Current requirement of a battery. For FLA roughly C/12, with C/10 being ideal.
So you use the larger panel wattage of the two.
If you use a PWM controller on a 150 AH battery requires 270 watts to generate 15 amps of charge current or, 200 watts on a MPPT system. That takes care of the minimum requirement. Now if you live in an area with say 2 Sun Hours would require a 275 watt panel with a MPPT 20 AMP controller.
Batteries also have a Max Charger Current they can accept, and on FLA is roughly C/8. On a 43 AH battery is only 5 amps to 6 amps. Any faster and you would risk burning your batteries up. See a problem yet? With a 43 AH battery and you pulling 360 WH/day would require you to charge them with 15 to 20 amps of C/3 to C/2 current to replace what you use in a day. . You would cook your battery.
If you design based on standard practices, everything falls into place.
Solar panel power must meet 2 conditions.
1. To replace what was used in a day under worse case conditions of winter short days. In your case 360 watt hours. That means the panels must generate either 720 watt hours with a PWM controller, or 550 watt hours for a MPPT system.
2. Must meet minimum Charge Current requirement of a battery. For FLA roughly C/12, with C/10 being ideal.
So you use the larger panel wattage of the two.
If you use a PWM controller on a 150 AH battery requires 270 watts to generate 15 amps of charge current or, 200 watts on a MPPT system. That takes care of the minimum requirement. Now if you live in an area with say 2 Sun Hours would require a 275 watt panel with a MPPT 20 AMP controller.
Batteries also have a Max Charger Current they can accept, and on FLA is roughly C/8. On a 43 AH battery is only 5 amps to 6 amps. Any faster and you would risk burning your batteries up. See a problem yet? With a 43 AH battery and you pulling 360 WH/day would require you to charge them with 15 to 20 amps of C/3 to C/2 current to replace what you use in a day. . You would cook your battery.
If you design based on standard practices, everything falls into place.
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