Wire from SCC to Breaker/Disconnect and on to busbar and battery

[DIDDLYV]

I have 4 210 watt solar panels that will be connected 2s each to its own EPever 40 Amp SCC.
Panel specs

• Power: 210 Watt
• 6 Busbar
• Monocrystaline
• Vmp: 22.42V
• Voc: 24.9V
• Imp: 9.37A
• Isc: 9.85A
• Maximum System Voltage: 600V
• J-Box is IP67 Rated with Diodes
• Cables: 12AWG, approximately 3 feet
• Wire size (leads on the back of panel)
• Height: 58.8125 in.

I have 10 Guage Solar Cables running down to the SCC thru a 20 amp breaker/cutoff which should be carrying approx 9-10 amps at 50 volts more or less this should convert to approx 38 Amps from the SCC to the batteries at 12 volts. Will I be able to run just the 10 guage wire to the 50 AMP breaker and busbars on to the batteries a distance of no more than 2 to 3 feet or should I plan on doubling up the 10 guage wire or bite the bullet and get a few feet of 8 or 6 guage wire. I might have some 6 left over from the AC runs to and from the MultiplusII.
Inquiring minds want to know!

 

[HRTKD]

10 gauge should give you a 2.08% voltage drop. 6 gauge is .85% voltage drop.

I chose to run 6 gauge between the solar charge controller and the common bus bars. My solar charge controller produces 50 amps, at most.

I assumed the following:
Amps: 40
Length: 6' (round trip, worst case)
Voltage: 12

 

[DIDDLYV]

Thanks got some 6 Guage wire prolly 2 x feet more than what I need but better to have and not need than need and not have.