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Double Checking My Solar Plan Sizing

ski247

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Joined
Apr 28, 2022
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I am looking for some feedback on my solar setup, as I want to make sure I get this right the first time!

Current setup is four 24v 200 watt panels (specs below) setup in Parallel using 2x 4 to 1 MC4 Branch Connectors. Where the confusion is coming for me is the sizing of everything from the Branch Connectors to the MPPT charger and finally to the 24v battery system. My understanding is that I need 4x 15 amp fuses prior to the branch connector, and 10 AWG coming out of the branch connector to the Victron MPPT 100V 50 amp 12/24-Volt Solar Charge Controller that I have. Then the wire from the charge controller to another 50a Blue Sea Circuit Breaker before the 24v battery system through the bus bar. The total wire run of everything is less than 20 feet as I am building this system for a van.

Some of what I have done seems oversized, but will that be okay? And are any of the wires or equipment I am using undersized? I appreciate in advance any advice y'all might have for me.

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[Specs for 4x Rich Solar Mega 200 Watt 24 Volt Solar Panels:]
Maximum Power(Pmax): 200W
Maximum Power Voltage(Vmp): 37.6V
Maximum Power Current(Imp): 5.32A
Open Circuit Voltage(Voc): 45.4V
Short Circuit Current(Isc): 5.83A
Maximum System Voltage(Vmax): 1000VDC
Temperature Range: -40°C ~ 90°C
Max Series Fuse Rating: 15A
 
Last edited:
I am looking for some feedback on my solar setup, as I want to make sure I get this right the first time!

Current setup is four 24v 200 watt panels (specs below) setup in Parallel using 2x 4 to 1 MC4 Branch Connectors. Where the confusion is coming for me is the sizing of everything from the Branch Connectors to the MPPT charger and finally to the 24v battery system. My understanding is that I need 4x 15 amp fuses prior to the branch connector, and 10 AWG coming out of the branch connector to the Victron MPPT 100V 50 amp 12/24-Volt Solar Charge Controller that I have. Then the wire from the charge controller to another 50a Blue Sea Circuit Breaker before the 24v battery system through the bus bar. The total wire run of everything is less than 20 feet as I am building this system for a van.

Some of what I have done seems oversized, but will that be okay? And are any of the wires or equipment I am using undersized? I appreciate in advance any advice y'all might have for me.

-

[Specs for 4x Rich Solar Mega 200 Watt 24 Volt Solar Panels:]
Maximum Power(Pmax): 200W
Maximum Power Voltage(Vmp): 37.6V
Maximum Power Current(Imp): 5.32A
Open Circuit Voltage(Voc): 45.4V
Short Circuit Current(Isc): 5.83A
Maximum System Voltage(Vmax): 1000VDC
Temperature Range: -40°C ~ 90°C
Max Series Fuse Rating: 15A
I have not tried to analyze your setup, but you may want to review this resource:


I am curious why you are doing all parallel vs Series or Seris-Parallel of the panels. Is it the voltage limit on the SCC?
 
Thanks for the direction and responses!

Being that the panels are on the roof of the van, I was avoiding series because of partial shade situations. But now I see that I need to switch to 2s2p for efficiency, as I read that I need the voltage to be at least 20v higher than the charging voltage for my 24v battery bank (28.8v).

So I am going to switch to the 150/30 MPPT, and 2 to 1 mc4 combiners. I will have 10 awg wire running down from the combiners to a 50a blue sea breaker that I can toggle on or off before the charge controller, and 10 awg from there to the ZCase bus bar where I can add another 50a fuse.
 
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