Help picking right lightning protection, fuses, and breakers for each of four strings

[timselectric]

I'm obviously new at this, so forgive my ignorance, but if each string has under 600 volts or 9 amps, it sounds like a 1000V breaker on each string is too much, unless it is the amp rating that I should focus upon.

No, you're right. I apologize.
I'm actually trying to carry on 3 conversations. lol
The amp rating is the trip setting.
The voltage rating, just means that it's safe to use on up to that voltage. Bigger is just safer.

 

[RevMikeB]

This calculator says 11.875 Amp breaker when inputting 5,700W, 600V, and 25 S.P. in calculator.

Breaker size calculator - Electrical

www.allumiax.com

 

[RevMikeB]

This calculator says 11.875 Amp breaker when inputting 5,700W, 600V, and 25 S.P. in calculator.

Breaker size calculator - Electrical

www.allumiax.com

So maybe a 15 amp breaker would work, considering most will only trip higher than the rating anyway.

 

[RevMikeB]

I think that you mean parallel.
In series, the voltage adds up.

Ok, so I'd need four of those DC breakers and four surge protectors. To wire, I bring the first string from the PV (+ & -) into the top of the breaker. The + & - are run out of the bottom of the breaker directly to line 1 (+ & -) DC input in the inverter. The surge protector is installed directly next to the breaker. I run a second thicker 6-gauge red wire and a second thicker 6-gauge black wire out of the bottom of the breaker from both + & - and loop it around to the top of the + & - of the surge protector. Out of the bottom of the surge protector, I run a thick green/yellow wire to the ground bar. Does this all sound correct, since the inverter has its own integrated DC shut off switch? I will do the same for each of the four strings to keep them independent of one another, since I want to keep everything in series and don't want anything run in parallel to double the current, which would overload the inverter.

 

[timselectric]

So maybe a 15 amp breaker would work, considering most will only trip higher than the rating anyway.

Sure

 

[timselectric]

I run a second thicker 6-gauge red wire and a second thicker 6-gauge black wire out of the bottom of the breaker from both + & - and loop it around to the top of the + & - of the surge protector.

I would connect the surge protector to the top/input of the breaker. No point in sending a possible lighting strike through the breaker. That just gets it closer to the inverter, before the suppressor can clamp it.
Hopefully, it will also trip the breaker.