Breaker for battery charger?

[mryimmers]

  Hi All;
I am putting together a small cabin solar system using a Midnite 125 amp DC mini disconnect box. Backup charging will be done with an
Iota DLS 45 amp charger (12Volt system). Should I be running the positive wire from the Iota  thru a breaker in the disconnect box ( say a 50 amp DC breaker) ?  And if so regarding the positive  wire to positive side of breaker, which side would be considered the "highest potential" the battery side or the charger side ?  My guess is the battery side, but I want to be sure.
       Thanks 

[vtmaps]

  Hi All;
I am putting together a small cabin solar system using a Midnite 125 amp DC mini disconnect box. Backup charging will be done with an
Iota DLS 45 amp charger (12Volt system). Should I be running the positive wire  thru a breaker in the disconnect box ( say a 50 amp DC breaker) ?  And if so regarding the positive  wire to positive side of breaker, which side would be considered the "highest potential" the battery side or the charger side ?  My guess is the battery side, but I want to be sure.   

The positive (sometimes marked 'line') side of the breaker goes to the battery. In the event of a fault only the battery can produce enough current to melt a wire. Make sure the wires are rated higher ampacity than the breakers.

Anything and everything that is connected to a battery must be protected by fuse or breaker. The breaker should be as close to the battery as possible, but not in the battery box. The cables from the battery box to the electric panel with the breakers must be in conduit.

Are you planning a grounded system on the DC side? If not, you must have fuses/breakers on both the positive and the negative connections to the battery.

--vtMaps