10AWG on Battery out w/ 40A breaker

[ricardo]

I recently completed a small backyard shed off grid PV install using the KID, but i stupidly ordered a 40A breaker for the battery out side. (thinking it should be 30A x 1.25, not realizing that midnite solar rates their DC breakers for 100% utilization).

I wired the KID battery out terminals to the 40A breaker with 10AWG (which i think is the largest size wire the wall mount accepts) - but i'm concerned that the 40A breaker is too large or 10AWG (90C THHN).

The distance is about 2 feet, maybe less.

Wondering if i should order a 30A DC breaker or just leave it as is.

The input solar is 600W, and the battery is a 24V 225 ah battery bank if that makes a difference.

[ClassicCrazy]

You are supposed to size the breaker according to the wire size.
For two feet I would try to fit in some 8 gauge wire.
If you look up a bunch of amp wire sizing charts you will find many  that say you can run 40 amps on 10 gauge wire but many say 30.
It really depends on the application and how much safety you want to build into it or if codes are important.

Larry

[ricardo]

right - thats the other option replace the wire run with #8 ..

the safest route would be #8 with a 40A breaker ... or #10 with a 30A breaker.

i had originally thought of runnign #6 from the charger to the battery (since i had extra #6 already lying around) -- but at the time of install realized that the #6 does not fit into the KID wall mount terminals.  (hence i ended up with #10 and the 40A breaker i had already purchased).  at least for now.

[ClassicCrazy]

Let us know if you fit the #8 in there - where there is a will there is a way !

Maybe it is possible to widen out the terminals a bit with a drill if it is too tight.

Larry

[ricardo]

since the cabling is alraedy neat at tidy in the MNDC -- i'm going to swap out the 40A braker with a 30A in the near future.. and leave the 10AWG in place.

[ricardo]

30A breaker arrived and was installed ...